Reverse Osmosis: Application in Zero liquid discharge


In water-short areas, wastewater reclamation has emerged as a practical option. Water shortage has emerged as a major issue as the world’s population grows and natural water supplies get depleted. It has been forecasted that the global demand for freshwater will exceed the supply by 40% by 2030.

It is expected that water scarcity will increase from about one-third to nearly half of the global urban population in 2050. Recovery and recycling of wastewater have become a growing trend in the past decade due to rising water demand. Most of the cost-effective water purification has been made possible via membrane treatment. Reverse Osmosis membranes have been demonstrated to significantly reduce total dissolved solids, organic pollutants, viruses, bacteria, heavy metals, and other dissolved contaminants.

Wastewater reuse, not only reduces the quantity and environmental threat of discharged wastewater, but it also alleviates the impact on ecosystems generated by freshwater withdrawal. Wastewater is no longer regarded as pure waste that may harm the environment if recycled, but rather as an additional resource that can be used to achieve water sustainability.

2. What is Reverse Osmosis?

Reverse osmosis (RO) is a membrane-based separation method that uses difference in the permeability of the water’s constituents. The membranes are made of a synthetic substance that is semipermeable; some constituents pass through it very easily, while others pass through it less readily.

To remove a constituent from water, water is forced across the surface of a membrane, resulting in product separation, which is why reverse osmosis (RO) is the best of all membrane filtration methods.

Schematic diagram of the Reverse osmosis process


The RO technique is utilized to remove dissolved solids because traditional municipal treatment methods are unable to do so. In chemical and environmental engineering, RO is increasingly employed as a separation process to eliminate organics and organic contaminants from wastewater. 

  1. Application of Reverse osmosis

 The use of reverse osmosis in wastewater treatment is limited by the high running costs caused by membrane contamination. In the case of industrial wastewater, RO has been employed in industries where it is possible to increase process efficiency by recovering valuable components that can be recycled in the manufacturing process.

An RO plant for industrial usage has the following goals:

  • 50% desalination of seawater and brackish water
  • 40% ultrapure water production for the electronic, pharmaceutical, and energy production industries and
  • 10% decontamination systems for urban and industrial water.


Some common applications of RO system include the following:

 (a) Desalination of the sea and brackish water.

 (b) Generation of high-purity water for pharmaceuticals.

 (c) Generation of ultrapure fresh water for microelectronics.

 (d) Generation of processed water for beverages (beer, bottled water, fruit juices, etc.);

 (e) Processing of dairy products.

 (f) Waste treatment for the recovery of process materials such as metals for metal finishing industries and dyes used in the manufacture of textiles.

 (g) Water reclamation of municipal and industrial wastewater.

  1. How does Reverse Osmosis work?

In Reverse osmosis, cellophane-like membranes separate pure water from polluted water. When pressure is applied to the concentrated side of the membrane, purified water is forced into the dilute side, and the rejected impurities from the concentrated side being washed away in the rejected water.


Permeate (or product) water is desalinated water that has been demineralized or deionized. The reject (or concentrate) stream is the water stream that contains the concentrated pollutants that did not pass through the RO membrane.

Salts and other contaminants are not allowed to pass through the semi-permeable membrane as the feed water enters the RO membrane under pressure (enough pressure to overcome osmotic pressure), and they are discharged through the reject stream (also known as the concentrate or brine stream), which goes to the drain or, in some cases, can be fed back into the feed water supply to be recycled through the RO system to save water.

Permeate or product water is the water that passes through the RO membrane and typically has 95% to 99% of the dissolved salts removed from it.

4.1. Stages of RO systems


Every RO system includes different types of filtrations. There are many filtration stages in a RO system. In addition to the RO membrane, every reverse osmosis water system also includes a sediment filter and a carbon filter. Depending on whether the filters are used before or after the membrane, the filters are referred to as prefilters or post-filters.

Each type of system contains one or more of the following filters:

      • Sediment filterfilters out particles such as dirt, dust, and rust
      • Carbon filterReduces the amount of volatile organic compounds (VOCs), chlorine, and other pollutants in water that give it an unpleasant taste or odor.
      • Semi-permeable membraneup to 98% of the total dissolved solids.


4.2. Technical Requirements of a RO System

Several fundamental technical prerequisites for a RO system include:

      • Feed water needs to be prefiltered and pH adjusted. After prefiltration, the feed water’s TDS and suspended particles should be kept under the specified ranges.
      • The microbiological quality of feed and product water should be monitored. If microbiological quality levels are exceeded, the system should be cleaned.
      • Before disinfection, every system component needs to be mechanically cleaned. To ensure that chemicals used in disinfection are eliminated from the system, the proper tests should be run.
      • It is best to avoid using filters or ion exchangers downstream of RO units.
      • The chemical and microbiological quality of water should be evaluated at predetermined intervals during a production cycle.
      • The RO system should be constructed for continuous flow without traps, dead ends, and pipe sections that may gather stagnant water. Installation of in-line conductivity sensors at strategic locations is necessary for ongoing water quality monitoring. The equipment should be qualified, and the RO system should be validated periodically, as well as operated and maintained according to the manufacturer’s instructions so that it can consistently produce water with acceptable quality.


5. What contaminants will Reverse Osmosis remove from water?

Reverse osmosis may remove up to 99%+ of dissolved salts (ions), particles, colloids, organics, bacteria, and pyrogens from the feed water.

  • However, the RO system cannot remove 100% of bacteria and viruses.

Contaminants are rejected by a RO membrane based on their size and charge. A properly operating RO system will generally reject any contamination with a molecular weight greater than 200. (For comparison a water molecule has a MW of 18). Similarly, the higher the contaminant’s ionic charge, the less probable it is to flow through the RO membrane.

6. ZLD combined with RO

RO is a technique for cleansing contaminated water using a membrane and a pressure unit. Furthermore, RO generates a large amount of liquid discharge, i.e. saline water. The Zero Liquid discharge system is used to limit discharge into streams and create a self-sustaining system with zero effluents.



Zero-liquid discharge (ZLD) is a water treatment technique that purifies and recycles all wastewater, resulting in zero discharge at the end of the treatment cycle. It is a cutting-edge wastewater treatment technique that combines ultrafiltration, reverse osmosis, evaporation/crystallization.

ZLD eliminates any liquid waste from exiting the plant or facility perimeter, with most of the water recovered for reuse. ZLD eliminates the danger of pollution associated with wastewater discharge and maximizes water usage efficiency, achieving a balance between freshwater resource exploitation and aquatic environment protection.

In order to increase energy and cost savings, reverse osmosis (Ro) has been added into ZLD systems. However, while RO is far more energy efficient than thermal evaporation.

Reverse osmosis for ZLD/MLD is constantly evolving, and the most efficient plants now have two concentration stages. The filtered wastewater is first forced through semi-permeable membranes at pressures of up to 80 bar, which reduces the water content by 40 to 50%. The liquid is forced through membranes at ultra-high pressures of up to 120 bar during the second step of the process, which reduces the water content by an additional 30 to 40%. It means that by the time the concentrate enters the brine concentrator following the two-stage reverse osmosis process, the water content has been decreased by up to 60%.


  1. Conclusion

RO is the best and most efficient desalination technique available today. The goal is to use RO to recover as much water from evaporation as feasible. Evaporation and Crystallisation is the most basic type of ZLD system, aiming for 90% water recovery and 100% crystallisation.

RO is currently the best and most energy efficient desalination method available. The goal is therefore to recover as much water as possible before evaporation using RO. As RO recovery rises, the cost of ZLD decreases.

Since water supplies are increasingly scarce, reuse options are growing in popularity. In this perspective, zero-liquid discharge (ZLD) is a new strategy for reducing waste, recovering resources, treating toxic industrial waste streams, and helping minimize water quality consequences in receiving water streams.

Although ZLD systems can reduce water contamination and increase water supply, their industrial-scale applications are limited due to their high cost and high energy consumption. Membrane-based technologies are an appealing future solution for industrial wastewater reclamation in ZLD systems.

8. Reference :

Introduction to Pipe sizes and pipe schedule

  1. Introduction

Pipe size calculation is necessary for planning and identifying the pipe to be utilized during project execution. The size of the pipe is determined primarily by

  1. the flow rate required,
  2. the pressure of the piping system, and
  3. the end connection equipment.

Identification of pipe size is vital for transmitting the exact idea from the piping design team to the piping execution team for using the correct pipe size for spool production. Pipe size also has a significant impact on cost. Oversizing a pipe result in additional costs, more complex pipe design, more footing, and, in some cases, process difficulties.

In the field of engineering, there are many and varied materials & types of pipes used, each   with their own unique credentials, and often with their own sizing. This results in some confusion in the industry around the outside diameter of piping, and the sizing of required pipe supports. That is why understanding to pipe sizing is very important.

Pipe size in referred in various terms like – Nominal Diameter (DN), Nominal Pipe Size (NPS), or Nominal Bore (NB). However, despite having certain similarities and variances in terms of their uses and places of origin, these are all notations for pipe sizes.

  1. Pipe sizing

Pipe size is specified with two non-dimensional numbers,

      • Nominal Pipe Size (NPS)
      • Schedule Number (SCH)

And the relationship between these numbers determines the inside diameter of a pipe.

  • Nominal pipe size and its importance


The Nominal Pipe Size (NPS) is a North American standard size for pipes that are suitable for high or low pressures and temperatures. It defines the diameter of pipe. Nominal pipe size only refers to the outside diameter (OD) of a pipe. When it is said that pipe size is 2 NPS, it indicates any pipes with an outer diameter of 2.375-inch (or 60.3 mm), regardless of wall thickness and hence internal diameter.

Nominal pipe sizing

Nominal Bore (NB) and Nominal Diameter (DN) are sometimes used alternately with Nominal Pipe Size (NPS). Nominal Bore (NB) is the European equivalent for NPS. The Nominal Diameter (DN) for NPS 5 and larger is equal to the NPS multiplied by 25.

Pipe size illustration

2.1.1 Nominal diameter (DN): The Nominal Diameter (DN), is frequently referred to as “mean or average outer diameter.” The metric unit system uses nominal diameter, sometimes known as Diameter Nominal (DN). The pipe’s Inner Diameter (ID) and Outer Diameter (OD) are not equal to the nominal diameter.

Although not exactly equal, the value of DN is close to the inner diameter of the pipe. The connecting dimensions of pipes and pipe fittings are denoted using this notation. Pipes come in a variety of DN sizes, and using standard tables and pipe schedule charts, the DN is used to determine the pipe’s final dimensions.

NPS vs DN measurement

2.1.2 Nominal Bore (NB): A European standard for indicating pipe size is Nominal Bore, or NB. In the case of pipes, the terms bore, and nominal refer to hollow structures, respectively. The nominal bore is a rough internal measurement across the diameter of the pipe. In other terms, a nominal bore refers to the pipe’s bore’s approximation in size.

 A pipe is exactly 10.75 inches long when measured in inches; hence, 10.75′′ x 25.4 = 273.05 mm. This is the reason why the outside diameter is not a straightforward number like 250NB.

Pipe Size Indication

  1. What is schedule Number?

The wall thickness of the pipe is described using steel pipe schedules. This crucial variable as it is directly related to the strength of the pipe and the suitability for specific applications.  Given the design pressure and permitted stress, a pipe schedule is a dimensionless number which is derived using the design formula for wall thickness.

Pipe wall thickness is determined by pipe schedule. The mechanical strength of the pipe increases as the wall thickness, allowing it to withstand higher design pressures.

Schedule number = P/S

  • P is the service pressure in (psi)
  • S is the allowable stress in (psi)

Two pipes of the same diameter with different schedules will have different wall thicknesses. So, when specifying a pipe for a high-pressure application, a larger number signifies a larger schedule (wall thickness).

Pipe schedule illustration

The schedule numbers 40 and 80 are the most popular ones. As the schedule number increases, the wall thickness of the pipe increases. Since there has been advancement of industrial age, pipe sizes and their standard has also been changed. There is wide range of wall thicknesses: SCH 5, 5S, 10, 10S, 20, 30, 40, 40S, 60, 80, 80S, 100, 120, 140, 160, Standard (STD), Extra Strong (XS) AND Double Extra Strong (XXS).

Steel pipe schedules are a way to specify the pipe’s wall thickness. This is an important metric since it is directly related to the pipe’s strength and applicability for various applications. A pipe schedule is a dimensionless number that is calculated using the design formula for wall thickness and the permissible stress.

4.  Conclusion

Pipe sizing is one of the first important actions a process engineer performs throughout the P&ID preparation process.  Pipe size is a key consideration in a well-designed process. It will have an impact on fluid velocity, pressure drop, flow regime, and so on. A poorly sized pipe can disrupt the entire process and, in extreme situations, lead to plant shutdown That is why one should always know about the differences between Nominal pipe sizes and pipe schedule numbers.

5.  Reference

Introduction to Air Quality standards for the classification of Compressed air quality

  1. Introduction

ISO (International Standards Organisation) is the world’s largest developer and publisher of international standards. An intermediary between the public and private sectors, ISO is a non-governmental organization. It has developed international standards to test the quality of compressed air. There are now three standards in use that are specifically related that directly relate to compressed air quality (purity) and testing:

  1. ISO8573 Series
  2. ISO12500 Series
  3. ISO7183

The most used standard is the ISO8573 Series and in particular ISO8573-1:2010. The ISO air quality standard measures three types of contaminants present in compressed air: water, oil content, and solid particles. It does not consider microorganisms and gases.

2.     What is compressed air quality & why it is needed?

When air is gathered to be compressed, more particles are also gathered, resulting in contaminated air. When air is compressed, the number of impurities present exponentially rises. Additionally, when compressing air, other pollutants could be included. To clean up the compressed air system’s pollutants, air treatment is required. The types of contaminants found in a compressed air system include:

  1. Solid particles / Dust
  2. Water (in liquid or vapor form)
  3. Oil content (in vapor or aerosol form)

Schematic presentation of contaminants present in compressed air

When air is adequately treated, it is considered clean and safe. However, the quality of compressed air is determined not just by how clean it is, but also by how dry it is. The number of particles of a specified size present in one cubic meter of air, the dew point, and the number of oil aerosols and vapor must all be counted to assess how clean and dry the compressed air is.

Compressed air is utilized in a variety of industries, including mining, manufacturing, textile manufacturing, and food processing. The air quality utilized in industrial applications has a direct impact on the work process, installed machines, and product quality. As a result, it is critical that the compressed air be clean and devoid of pollutants.

The smaller the chance of contamination, breakdowns, and product rejection, the cleaner the air. This is especially important in businesses like food and beverage and pharmaceuticals. There is a possibility that the air will come into direct touch with the product or will come into indirect contact with the packaging.

  1. Classification of Compressed air quality

Compressed air is the only utility created by the end user of all the key utilities used in the food manufacturing setting. This means that the end-user has a direct impact on the quality of this energy source.

High-quality compressed air is essential for producing food that is not only cost-effective to process but also safe to consume. Therefore, choosing the appropriate compressed air equipment for food processors is in the best interests of everyone. The basis for choosing air treatment products is made much easier by the ISO 8573 air quality standards and ISO 12500 compressed air filter standards.


      Standards used for air quality measurement

  1. What is ISO 8573 & how it defines different air purity classes?

ISO 8573 is the compressed air quality standard. ISO8573 is a series of international standards that address compressed air quality (or purity). Part 1 of the standard describes the compressed air quality requirements, and parts 2 through 9 detail the testing techniques for various pollutants.

  • ISO 8573-1: Contaminants & purity classes
  • ISO 8573-2: Oil aerosol test methods
  • ISO 8573-3: Humidity test methods
  • ISO 8573-4: Solid particle test methods
  • ISO 8573-5: Oil vapor test methods
  • ISO 8573-6: Gas test methods
  • ISO 8573-7: Viable microbiological content tests
  • ISO 8573-8: Solid particle test methods by mass concentration
  • ISO 8573-9 Liquid water test method


       Various air quality classes


This above standard also determines air quality, which is designated by the following nomenclature: Compressed Air Purity Classes A, B, C:
A= Solid particle class designation
B= Humidity and liquid water class designation
C= Oil class designation

Air quality designation

5.     Why is it important to consider the air quality?

Compressed air can contain unwanted substances, such as water in drop or vapor form, oil in drop or aerosol form, and dust. Depending on the compressed air’s application area, these substances can impair production results and even increase costs. Air treatment aims to produce the compressed air quality specified by the consumer. When the role of compressed air in a process is clearly defined, finding the system that will be the most profitable and efficient in that specific situation is simple. This will be determined by your finished product and the working environment of your application.

6.     What does Class 0 mean for air quality?

It is recommended that only compressed air classified as Class 0 be used in critical processes to eliminate the risk of air contamination. This level of classification does not mean zero contamination. Class 0 refers to the highest air quality possible with minimum contamination present in the air and must be lower in contamination than Class 1.

A combination of compressed air equipment can be installed to produce clean air. This may include various air filters and dryers. Identifying which contaminants need to be removed will help you to determine which equipment you need.

  1. Conclusion:

A specific compressed air class is assigned depending on the number of contaminants found. The air quality class is set according to ISO 8573-1. This standardized system defines parameters from the least to most contaminated sources of compressed air. These standards are very much useful when it comes to selecting air compressors/ compressed air systems for industrial purposes. As Compressed air is a vital energy source and is utilized in multiple operations in a food processing facility.

When properly treated, compressed air is regarded as a safe, clean utility, as compared to other energy sources. It is ultimately used to package, wrap, seal, palletize and label food products prior to storage or shipment. ISO 8573 is a European Standard that describes contaminants in compressed air and defines purity classes for them. This multi-part standard also defines approved measurement methods for testing contamination levels.

  1. Reference


Insight into Food Quality Measurement

What is considered food quality?

Food Quality is the quality that the consumer finds acceptable in food service. The food quality parameter includes external elements like aspect (size, shape, brightness, and color), texture, and taste. Other features include internal components and legal quality standards (chemical, physical, microbiological). Many consumers base their decisions on production and processing norms, citing substances with dietary, medicinal, or nutritional requirements (for allergies or diabetes, for example). Food quality is intimately tied to health and hygiene standards and includes traceability and labeling.

Importance of Quality Control

  1. Decrease in production costs

Companies in the food sector can significantly lower their production costs by implementing effective inspection and control in the production processes and operations. Production expenses are further raised by wastage and poor product quality. Quality control monitors the creation of subpar goods and wastes, which significantly lowers the cost of production.

  1. Improved goodwill

Quality control boosts the company’s reputation in the public eye by creating goods of higher quality and meeting client needs. As a result, the brand gains a solid reputation and favorable word-of-mouth marketing on offline and online platforms. A well-known company can readily raise capital from the market. Additionally, a company’s chances of surviving in the fiercely competitive market are better with improved goodwill.

  1. Simplifies pricing

Companies in the food business can ensure that uniform products of the same quality are produced by implementing quality control techniques. This considerably simplifies the issue of food product price fixing. Additionally, this removes the concern over commodities’ prices fluctuating continually.

  1. Improved Sales

Quality control ensures that high-quality items are produced, which draws more customers to the product and boosts sales. It is crucial in sustaining and generating new demand for the company’s products. Additionally, increased social media usage has increased the need for brands to stay alert constantly. Any unfavorable feedback from a customer could harm the brand’s reputation.

  1. Improved Production Methods

Quality control ensures that goods are produced according to the desired standards and at reasonable rates. Quality control ensures better methods and designs of production by providing technical and engineering data for the product and manufacturing processes.

  1. Enhanced employee morale

An efficient quality control system is beneficial in raising staff morale. Employees are more inclined and motivated to work toward the firm’s goals when they believe they are employed by a company that produces sound, high-quality products. Additionally, these workers are more likely to adhere to the organization’s criteria for quality control in their work.

What are Food Quality Testing Parameters?

Any food characteristics used to gauge quality can be called quality parameters. However, the specific features assessed can vary since quality can mean different things to different people along the food supply chain.


The following parameters are commonly used in food quality testing:

These quality parameters are used alone or in various combinations depending on the needs of a stakeholder in the food supply chain.

Broad Categories of Food Quality Measuring Instruments 




A separate industrial sector is expanding with food science research and practice to create and deliver the precise instruments required to measure and monitor numerous quality indicators. One of the most widely used methods is near-infrared spectroscopy, which is suitable for determining the quality and quantity of organic molecules. Together with those made for post-harvest gas analysis, these tools are actively enhancing the production of fresh fruits and vegetables, paving the way for more earnings and more environmentally friendly practices.



FSSC 22000: A brief insight

What is FSSC 22000?

With the industrialization of food, there is an increasing need for affordable, safe, and good-quality food products. FSSC 22000 provides a brand assurance platform to the food industry. Food Safety System Certification 22000 (FSSC 22000) is an internationally accepted certification scheme for certifying and auditing food safety within the food and beverage industry. It is accepted worldwide because it is recognized by Global Food Safety Initiative (GFSI).

What is the backbone of FSSC 22000?

FSSC22000 is based on 3 components:

  1. ISO22000- Provides a basic framework across the entire framework.
  2. PRPs- Includes requirements derived from BSI, PAS, and ISO Technical Specification Standards.
  3. FSSC22000 Additional Requirements- Covers those requirements missed in ISO22000 and PRPs.

Aims and Objectives

  1. Create and maintain an accurate and reliable register of certified organizations that have demonstrated that they meet the system’s requirements.
  2. Support the accurate application of food safety and quality management systems.
  3. Promote national and international recognition and acceptance of food safety and quality management systems.
  4. Provide information and campaigns on food safety and quality management systems and support for the certification of food safety management systems in food safety and quality.

Which organizations can get FSSC22000 certification?

FSSC supports the whole food supply chain. It covers:

  • Processing of ambient stable products
  • Production of feed
  • Production of pet food (only for dogs and cats)
  • Production of pet food (for other pets)
  • Catering
  • Retail /Wholesale
  • Provision of transport and storage services for perishable food and feed
  • Provision of transport and storage services for ambient stable food, feed, and packaging materials
  • Production of food packaging and packaging materials
  • Production of Bio-chemicals

Difference between FSSC 22000 and FSSC 22000 QUALITY

Combining FSSC 22000 and ISO 9001 is called FSSC 22000 QUALITY. FSSC 22000 QUALITY is for an organization that wishes to integrate its Food Quality Management System into the scope of certification.

Audit and Certification Process of FSSC 22000

The certification process and audit proceeds according to the steps below:

  1. Initial Certification Audit – The initial certification audit includes: – fixing a mutually convenient date for both the certification body and the applicant, applicant, ensuring that it has all the required documents, staff members, and all the operations and processes ready to be audited on the audit day.
  2. The two Stages for the FSSC 22000 Audit –
    • STAGE 1: Stage 1 verifies that the applicant follows the FSSC 22000 standards, own internal documents, and regulations of the country. The applicant organization must have at least six months of verifiable records for the audit. After review, it will include “areas of concern,” which will be categorized as Major or Minor areas of concern. Finally, the applicant will have up to 6 months to fix the errors. The main objective of this stage is to assess the preparedness for stage 2 of the organization.
    • STAGE 2: In stage 2, activities subjected to the proposed certification shall be assessed and shall take place during the initial six months after stage 1. The site shall be fully operational during the audit. Applicants are issued with either Minor, Major, or Critical findings. In the case of Major and Critical results, the certificate will be issued once these issues are resolved.
  3. Certificate Issue – After all the issues have been resolved to the auditor’s satisfaction, the Certification Body shall issue a certificate which essentially gives assurance that all the standard’s requirements have been met.
  4. Surveillance Audits – After the certification is issued, annual surveillance audits shall be conducted within the three-year, of which at least one must be unannounced.
  5. Recertification Audits – Recertification audits are conducted every three years and usually coincide with a newer version of FSSC 22000. It is a complete audit that encourages the latest compliance and demonstrates the organization’s competence.


Why FSSC 22000?

  • Economical – Organizations can pay all at once or divide the payment over three years. It is economical compared to other schemes, such as British Retail Consortium (BRC), where the organization should pay annually.
  • Valid for three years – Once certified, the organization does not have to worry about certification for three years if they maintain the given standard.
  • Benefit of Surveillance Audit – The auditors will audit each year, which provides room for improvement, if any.


FSSC 22000 is designed to help an organization establish and control and improve its food safety management. The scheme is recognized by GFSI (Global Food Safety Initiative) and is accepted worldwide.

FSSC 22000 integrates quality management with food safety by including all the requirements of ISO9001, making it a one-stop solution for an organization that wishes to incorporate quality into the scope of certification.

It ensures visibility up and down the supply chain. The scheme has both flexibilities with accountability, meeting the needs of individual organizations.



Single Line Diagram (SLD)

1. Introduction

Single-line diagram (SLD) is also known as a one-line diagram. It is a high-level diagram that shows how incoming power is distributed to the equipment. It is the first step in preparing a critical response plan, allowing you to become thoroughly familiar with the electrical transmission system layout and design.

The single-line diagram also becomes your lifeline of information when updating or responding to an emergency. An accurate single-line diagram ensures optimum system performance and coordination for all future testing and can highlight potential risks before a problem occurs.

An effective single-line diagram will clearly show how the main components of the electrical system are connected, including redundant equipment and available spares. It shows a correct power distribution path from the incoming power source to each downstream load – including the ratings and sizes of each piece of electrical equipment, their circuit conductors, and their protective devices.

Whether you have a new or existing facility, the single-line diagram is the vital roadmap for all future testing, service, and maintenance activities. As such, the single-line diagram is like a balance sheet for your facility and provides a snapshot of your facility at a moment in time.

2. Scope of SLD

To give you an accurate picture of your electrical system, the single-line diagram information normally includes:

    1. Incoming lines (voltage and size)
    2. Incoming main fuses, potheads, cutouts, switches, and main/tiebreakers
    3. Power transformers (rating, winding connection, and grounding means)
    4. Feeder breakers and fused switches
    5. Relays (function, use, and type)
    6. Current/potential transformers (size, type, and ratio)
    7. Control transformers
    8. All main cable and wire run with their associated isolating switches and potheads (size and length of run)
    9. All substations, including integral relays and main panels and the exact nature of the load in each feeder and on each substation
    10. Critical equipment voltage and size (UPS, battery, generator, power distribution, transfer switch, computer room air conditioning)

3. Uses & Significance

Single-line diagrams are used by several trades including Electrical, Mechanical, HVAC, and plumbing, but the electrical one-line diagram is the most common. HVAC and plumbing riser diagrams are essentially one-line diagrams, but they go by different names.

An electrical single-line diagram is a representation of a complicated electrical distribution system into a simplified description using a single line, which represents the conductors, to connect the components. Main components such as transformers, switches, and breakers are indicated by their standard graphic symbol. The overall diagram provides information on how the components connect and how the power flows through the system.

4. Flow Diagram of SLD

Few parameters are considered while designing the flow of a single-line diagram to keep it simple & readable:

    1. Remember to use a single line to represent multiple conductors.
    2. Diagrams should start at the top of the page with the incoming source of a system’s power.
    3. Electrical symbols must be used while drawing the single-line diagram to make it simple & concise.
    4. No physical location or size representation is required of the electrical equipment only ratings and breakers sizes with the other equipment to be used should be written.

5. Designing of SLD

To Design a single-line diagrams for your facility Some steps need to be taken:

    1. Create an inventory of all the utilities & equipment used in the building.
    2. Verify its existence and that they are adequately available.
    3. Confirm loads are connected to emergency/standby feeders.
    4. Verify potential single points of failure.
    5. Evaluate design redundancy of critical systems
    6. Make a report that outlines the findings by site along with recommended actions.
    7. Provide a copy of the single-line electrical diagram in AutoCAD format
    8. An up-to-date single-line diagram is vital for a variety of service activities including:
    9. Short circuit calculations, Coordination studies, Load flow studies, Safety evaluation studies, All other engineering Studies, Electrical safety procedures & Efficient maintenance, etc.

6. Calculations Requirements for SLD

6.1.     Identify the appropriate symbols:

To draw and understand a single-line diagram you first need to be familiar with the electrical symbols. This chart shows the most frequently used symbols. For electric power networks, an appropriate selection of graphic symbols is the most important step.

6.2.    Draw the required system:

To draw the electrical single line diagram first we need all the information on electrical equipment and the supply of receiving power. The most important information to include is:

          • Incoming service voltage
          • Equipment rated current
          • Identification of names of equipment
          • Bus voltage, frequency, phases, and short circuit current withstand ratings
          • Cable sizes, runs of cables, and lengths
          • Transformer connection type, kVA, voltages, and impedance
          • Generator voltage and kW
          • Motor HP
          • Current and Voltage ratios of instrument transformers
          • Relay device numbers

6.3.    Related calculations:

To represent the three-phase system in a single line diagram various other cal. are required:

          • Calculation Of generator reactance
          • Calculation Of transformer reactance
          • Calculation Of transmission-line reactance
          • Calculation Of reactance of motors and other equipment etc.

7. Software’s used 

7.1 AutoCAD

AutoCAD Electrical has a schematic library and a single line diagram sub-library. This enables the user to place two different representations down of the same component.

7.2 ETAP

ETAP Single-Line Diagram / View is an intelligent user interface to model, validate, visualize, analyze, monitor, and manage electrical power systems, from high to low voltage AC and DC networks.

7.3 Eco-dial

It is a low voltage electrical installation design software developed by Schneider Electric. it is a user-friendly software that helps you optimize equipment and costs while managing operating specifications, all along with the design of your power distribution projects.

7.4 Microsoft Visio

Visio Professional or Visio Plan 2 are used to create electrical and electronic schematic diagrams.


8. Benefits of SLD:

    • Help identify fault locations which identify when to perform troubleshooting & simplify troubleshooting
    • Identify potential sources of electric energy during the distribution process.
    • Accurate single line diagram will further ensure the safety of personnel work
    • Meets compliance with applicable regulations and standards
    • Ensure safe, reliable operation of the facility

9. Reference:


Process Control System in Food Industry

  1. Introduction:

Process control systems (PCS) also known as industrial control systems (ICS) are an integral part of the food & dairy processing industries. It is basically a tool that ensures plant efficiency and reliability. Process control systems function as pieces of equipment along the production line during manufacturing that tests the process in a variety of ways and returns data for monitoring and troubleshooting.

Food and Dairy products have a very vast application which ranges from dairy products to beverages and even bakery items, to fulfill this large demand food processing equipment with a control system is used to execute the various unit operations necessary during a complete production cycle.

  1. Objectives:

The need to install a process control system is to improve the economics of the process by achieving, the following objectives:

    • Reduce variation in the product quality,
    • Achieve more consistent production and maximize yield,
    • Ensure process and product safety,
    • Reduce manpower and enhance operator productivity,
    • Reduce waste and
    • Optimize energy efficiency

Mainly two common classes of control actions are used in industries:

    1. Manual control: In manual control, an operator periodically reads the process parameter. When the value changes from the set value manual process are required to control the operating process.
    2. Automatic control: In automatic control, the process parameter is measured by various sensors & instrumentation which is controlled by using control loops.

All process control configurations whether manual, automatic, or computerized mainly have three essential elements:

    1. A measurement
    2. A control strategy
    3. A feedback element

Regardless of the nature of the product and process. Control in food processing has moved on from just attempting to control single variables, e.g., level, temperature, flow, etc., to systems that ensure smooth plant operation with timely signaling of alarms. Process control systems also work to gather and transmit data obtained during the manufacturing process.

These are:

    1. Supervisory control and data acquisition (SCADA)
    2. Manufacturing execution systems (MES)
    3. Enterprise resource planning (ERP)

  1. Supervisory Control & Data Acquisition (SCADA):

SCADA is one automation solution that can improve production efficiency and increase profitability. In the food processing industry, SCADA is used to ensure food quality and to achieve production goals. All phases of food preparation are typically monitored and controlled by SCADA. SCADA is also used to control the exact mix of ingredients as well as the time and temperature required to process foods. This prevents foods from being spoiled due to a heating process that was off by a few degrees. SCADA applications are also important in food production to document the fact that the production process meets industry standards and complies with governmental regulations.

Nowadays SCADA systems can do more than simply collect data and operate devices. They use artificial intelligence (AI) to analyze data and make decisions without the help of humans. They can operate in a cloud environment so that SCADA monitoring and control can be accomplished remotely by using tablets and smartphones.

SCADA is used to control and monitor all operational technology (OT) in the plant. And at the same time also sends and receives information from the MES or ERP system For Information that has to do with business planning & scheduling.

SCADA works in the following way:

    • SCADA begins by communicating directly with controllers in the field in real-time, typically through a PLC or RPU.
    • Then the SCADA system gathers all the data obtained from connectors in the field and transfers it to SCADA itself.
    • Later the data is shown graphically to operators that are executing whatever process.

There are many areas in food/dairy industries where SCADA is used to optimize production:

    1. Packaging
    2. Recipe Re-creation
    3. Maintaining Quality standards
    4. Visualization of products
    5. Creation of reports

4. Manufacturing execution systems (MES):

Manufacturing execution systems (MES) are computerized systems used in manufacturing to track and document the transformation of raw materials to finished goods. MES works as a real-time monitoring system to enable the control of multiple elements of the production process (e.g., inputs, personnel, machines, and support services).


MES software can do more for food and beverage manufacturing companies than traditional management. It can:

    • Optimize your shop floor on the go.
    • Identify issues or potential problems before they happen.
    • Integrate easily with existing systems.
    • Empower employees with the data and insights to make manufacturing smarter.
    • Remove non-value-adding actions and anecdotal evidence of losses.
    • Build a reputation of trust and quality with the supplier base using auditable, quality data.

Five things your food industry MES system should have:

    1. User-Friendly Operator Interfaces –The golden rule of developing software for the food processing industry plant floor is that must be easy to use.
    2. Integration to Production Equipment – Food manufacturing production equipment is filled with valuable data and can be used to streamline and optimize manufacturing processes.
    3. Offline Operating Capability- manufacturing processes are network dependent then they will come to a screeching halt if the network fails. MES should have offline operation capability in Your food industry.
    4. Food Industry-Specific Functionality – Modern MES systems and especially one developed specifically for the food manufacturing industry will manage more challenges, making them the ideal solution for your production management and data collection needs.
    5. Food Industry-Specific Modularity –In the same vein, a food industry MES system will likely feature software modules that align well with your production processes.
  1. Enterprise Resource Planning (ERP): 

Enterprise Resource Planning refers to a software system which are used for business management. An ERP system enables food companies to manage and optimize their business processes – from purchasing, accounting, finance, human relations, and production to logistics. In short, ERP is the software that keeps your business up and running.

An ERP software for the food industry helps you introduce new products to market faster and cheaper than competitors & also ensures absolute compliance to the food safety regulations.

There are a few must-haves in ERP System:

    1. The ERP software must be able to supply precise cost information for all components, such as finished products, joint products, and byproducts. This is essential for the calculation of material and manufacturing costs as well as for pricing.
    2. Make sure that the system does not have any problems with portraying and optimizing recipes, bills of materials, and product calculations.
    3. Evaluations, gross margins, monitoring of processes and products: only if essential information and key performance indicators can be retrieved from the ERP system at the press of a button will decision-makers be able to get the most out of their business.
    4. The software must allow automated handling of variable weights. Otherwise, you will run into problems in weight price labeling, especially with non-equalized products.
    5. Production planning must take requirements of the fresh goods production into account.

Advantages of ERP:

    • Cost reduction: Save the investments in your own server, other expensive hardware, and skilled staff (which are quite hard to find these days)
    • Savings in time: No need to worry about keeping your ERP system and the hardware up to date. This will save you precious time.
    • Scalability: Add or remove IT resources cost-efficiently and in a very short time.

Benefits of Process Control System: 

    • Reduces wastage of expensive compounds
    • Provides improved production reliability
    • Increases productivity & quality
    • Improve the consistency of the product
    • Minimize the influence of external disturbance
    • delivers the continuous data required to meet regulatory standards
    • Standardized business processes

7. Reference:

    • Process Control in Food Processing Article Written by Keshavan Niranjan, Araya Ahromrit and Ahok S. Khare


Process Control Equipment in Food Industry

  1. Introduction:

Process control equipment in the food industry are the types of equipment that measure the variables of a technical process, direct the process according to control signals from the process computer system, and provides appropriate signal transformation. Examples of process control equipment include actuators, sensors, transducers, etc.

These are the equipment used to ensure that food processing equipment operates correctly and the processing stages are continued as specified SOP.

These are equipment, that can be used

    • to analyze ingredients and machines,
    • allowing manufacturers to perform and duplicate processing procedures.
    • monitor existing systems and machinery, such as logging data during product testing or quantifying typical performance statistics.

Control equipment’s are particularly crucial during food production, as minor changes in cooking temperature, ingredient ratios, and operation times can lead to drastic changes in the finished product. 

  1. Objective:

The main objective to implement control equipment’s in the food industry is to improve the economics of the process by achieving the following objectives: 

    • Reduce energy consumption and increase versatility
    • Enable cost-effective operation of the manufacturing process
    • Reduce the air consumption of pneumatically operated valves
  1. Sensors:

In the food industry sensors are designed with process connections for clamping directly onto the process. They have a high mechanical strength to withstand the temperature and pressure associated with food production. The use of sensors to monitor temperature throughout the production process helps to ensure an optimum final product and assures food safety.

3.1 Sanitary Sensor:

Hygienic Pressure Transmitters are used in food & dairy application mainly with strong features like high-performance, long-term stability, high performance of temperature characteristics, etc. To accomplish these objectives many types of sanitary sensors are used in the food industry. Few are listed below:

        • Hygienic Adapter System (Fluid less Type): This system composes of replaceable adapters (16 adapters in total) with the hygienic function of pressure detection. fluid less type’s pressure sensor doesn’t need liquid such as silicon oil. It adapts duplex stainless steel as a sensor material. This duplex stainless-steel material has both high corrosion resistance and high tension.

        • Digital Remote Sensor (DRS): Transmitter connects two pressure sensors, master (high-pressure side) and slave (a low-pressure side) in a remote location, with DRS dedicated communication cable to measure differential pressure. These are suitable for various kinds of pressure measurement.

        • Differential/gauge pressure diaphragm seal: Diaphragm Seal System consists of differential pressure or gauge pressure transmitter with one or two diaphragm seals.  Suitable for various kinds of pressure measurement.

        • Distributed Temperature Sensor: These sensor is capable of intelligently monitoring temperature distribution up to 50 km in the lengthways direction in real-time with the help of a fiber optic sensor cable. This helps achieve fire detection, fire prevention, and preventive maintenance of equipment over a wide area which has up till now been difficult with thermocouples, resistance temperature detectors, or radiation thermometers. DTSX supports the HSE (Health, Safety, and Environment) plus the maintenance of plants and the social infrastructure, and aids safe operation.

When a large-scale fire or equipment failure causes the production line to stop, the damage is not limited to just customers’ assets or loss of revenue opportunity, but the supply chain is also affected. The economic and social loss is immeasurable. DTSX can precisely identify abnormally hot locations as a fiber optic sensor cable is installed along the length of the measurement target. This enables a quick initial response for safety, which ensures that the operation of the plant and social infrastructure is maintained, and the customers’ assets and social credibility are protected.

        • Tunable Diode Laser Spectrometers (TDLS):

It allows real-time gas analysis to increase efficiency, safety, quality, and environmental compliance. The non-contacting sensor allows measurement under severe conditions, such as high temperature, high pressure, corrosive/abrasive conditions, high dust concentration, etc. Maintenance can also be performed without taking the process offline because the TDLS is isolated from the process. The TDLS is a robust process analyzer that contributes to stable and efficient operation.

        • Sushi Sensor:

To improve the availability ratio and profitability of plants, timely identification of health conditions and efficient maintenance of aged equipment are required. Various sensing technologies are needed to monitor conditions and maintain diverse equipment. To maintain equipment distributed across a plant efficiently with limited man-hours, quantification of measurement data and automated data acquisition and storage systems are required Sushi Sensor measures vibration, temperature, and pressure as data for maintaining equipment.

        • Level sensor:

level sensors are used for in-line measurement and control of the food processing operation. Typically, they may be used to monitor temperature and liquid levels rates, acid/alkali inputs, and gas flow. For example, a level sensor is used to determine specific volumes of liquid dispensed during the cooking phase, too much or too little may mean the product is spoiled. So, to take care of this level sensors are used in the food industry.


        • Coriolis Mass Flowmeters: 

Coriolis mass flow meter, which is widely considered the most accurate type of mass flow meter and is widely used in industrial applications for accurate measurement. Coriolis flowmeters feature instrumentation that function on the principles of the Coriolis effect – a notable (and strange) phenomenon whereby a mass moving in a rotating system experiences a force acting perpendicular to the direction of motion and the axis of rotation.

Application of this includes Batching, Dosing, Blending, Chemical injection, High-pressure gases, Liquid and gas low flow measurement, Precision coatings, R&D laboratory, Vacuum thin film coating, etc.

Typical Food Sensor Applications: 

      • Storage vessels – pumps and valves
      • Food processing monitoring systems, alarms, and alerts
      • Water purification
      • Liquid level sensing for industrial food processing operations
      • Cryogenic fast freeze technologies
      • Food test laboratories
      • Liquid gas storage
      • Transport
      • Liquid dispensing
      • Solvent and chemical control 


  1. Actuators:

Efficient food processing and packaging operations call for high-level robust technologies that are durable, precise, and safe for food. Various food industry procedures including cutting and slicing of raw materials and filling beverages, which need to be done systematically, without any contamination. To fulfill these demands, actuators are used at a high speed and with maximum efficiency.

An actuator is a device that produces a motion by converting energy and signals going into the system. The motion it produces can be either rotary or linear. Linear actuators, as the name implies, produce linear motion. This means that linear actuators can move forward or backward on a set linear plane – a set distance they can travel in either direction before they must stop. Rotary actuators on the other hand produce rotary motion, meaning that the actuator revolves on a circular plane.

Linear or rotary actuators are available in various forms depending on the power-supply source.  The actuator could be electrical, pneumatic, or hydraulic. The choice of actuator type used will most likely depend on the application and industry-specific requirements. For example, the natural choice for the food industry would be electrical actuators.

4.1 Electrical Actuators:

Electric Linear Actuators are a crucial part of food processing and packaging systems. They allow you to control your production more efficiently by providing motion to the machines at required speeds. In addition to this, they help in eliminating potentially harmful fluid-powered systems from the food production environment. Vowing their uses, electric actuators are widely used in the following areas: 

          • Conveyor Process
          • Bread Robots
          • Packaging Robotics
          • Ergonomic Stations

4.1.1: Benefits of Electric Actuators in the Food Industry:

Electric actuators offer various advantages for many industries, and the food industry is one of those. They are designed to perform in a rough and challenging environment. Here are a few benefits:

          • Speed up Operations
          • No Fluid Leakage
          • Hygienic Design
          • Corrosion resistance
          • Clean and Robust Actuator Technology


4.1.2: Disadvantage of Electric Actuators in the Food Industry:

Apart from various advantages, Electric actuators have a few disadvantages too:

          • lower speed than pneumatic and hydraulic actuators
          • less suitable for very heavy loads

      • Pneumatic Actuators: 

Pneumatic actuators are found in automated systems and machinery in every industry and come in a wide range of sizes, styles, and designs. Easy to maintain, they can operate at high speeds, offering tremendous flexibility and value for a seemingly endless number of applications. In addition to being fast, economical, and reliable, pneumatic actuators are also cleaner and safer than other solutions, which make them ideal for manufacturing, packaging, palletizing, material handling, food, and beverage, and many more applications.

Pneumatic actuators are devices that use compressed air to power motion. That motion can be along a rotational or linear path, ultimately assisting or performing a task such as pushing, pulling, gripping, turning, feeding, ejecting, opening, closing, holding, stopping, clamping, stamping, and, as you can guess, the list goes on. The forces that these actuators can produce depend primarily on the cylinder bore size (piston diameter) and the operating pressure, but rod size is also a very important consideration on the rod-style cylinder. 

  1. Transducers: 

A transducer can be anything that converts one form of energy to another. transducers that are used in food industries are piezoelectric, but some are magnetostrictive also. Piezoelectric transducers convert cyclic electrical current into physical vibrations, and magnetostrictive devices convert varying magnetic fields into physical vibrations.

5.1 Piezoelectric Transducer: 

A piezoelectric transducer (also known as a piezoelectric sensor) is a device that uses the piezoelectric effect to measure changes in acceleration, pressure, strain, temperature, or force by converting this energy into an electrical charge. The word piezoelectric is derived from the Greek word piezen, which means to squeeze or press. The piezoelectric effect states that when mechanical stress or forces are applied to a quartz crystal, produces electrical charges on the quartz crystal surface. The rate of charge produced will be proportional to the rate of change of mechanical stress applied to it. Higher will be stress, higher will be voltage.     

5.2 Magneto-strictive Transducer: 

A magnetostrictive transducer makes use of a type of magnetic material in which an applied oscillating magnetic field squeezes the atoms of the material together, creating a periodic change in the length of the material and thus producing a high-frequency mechanical vibration. Magnetostrictive transducers are used primarily in the lower frequency ranges and are common in ultrasonic cleaners and ultrasonic machining application 

  1. Reference: 

Control System in Food Industry

  1. Introduction:

A control system manages, commands directs, or regulates the behavior of other devices or systems using control loops. It can range from a single home heating controller using a thermostat controlling a domestic boiler to large industrial control systems which are used for controlling processes or machines.

It is one fully integrated system that provides the synchronization of all applications and devices involved in the manufacturing process. This allows for the successful merging of information flow from the distributed control system (DCS) and supervisory control and data acquisition (SCADA) systems so that it is available in one interface in real-time. And one of the best means of unifying these communications is by using a single industrial software system.

In the food industry control system is a means of computerizing best practices within a food & beverage factory, restaurant, or catering operations. It gives managers a better idea of the flow of food processing as food processors are becoming increasingly aware of the power of data-driven insights to optimize their use of raw materials, enhance food quality and safety, and guarantee traceability and support for continuous improvement.

It also helps industry owners to introduce the same financial rigor to dining establishments or catering companies that make manufacturing operations more effective. At the sharp end, it provides the food industry with a more structured way of planning operation, considering nutritional and financial considerations.

  1. Objective:

The main objective to implement control system in the food industry is to improve the economics of the process by achieving the following objectives:

  • Reduce variation in the product quality, achieve more consistent production and maximize yield,
  • Ensure process and product safety,
  • Reduce manpower and enhance operator productivity,
  • Reduce waste and
  • Optimize energy efficiency

The Control system becomes essential nowadays as both consumers and regulatory bodies demand complete transparency and the highest food quality. They want to understand every step of a product’s journey: where all its ingredients came from, how it was made, its nutritional value, and if it was ethically sourced. Therefore, it’s essential to have a digital control system that records & provides feedback on every step of a product’s journey.

  1. Types Of Control Systems:

There are two common classes of control action: manual control (open loop) and automatic control (closed-loop).

3.1. Manual control: This type of operation depends on the skill of individual operators in knowing when and how much adjustment to make. Therefore, manual control may be used in those applications where changes in the manipulated parameter cause the process to change slowly and by a small amount. This is possible in plants where there are few processing steps with infrequent process upsets and the operator has sufficient time to correct before the process parameter overshoots acceptable tolerance. Otherwise, this approach can prove to be very costly in terms of labor, product inconsistencies, and product loss.

3.2. Automatic Control: In automatic control, the process parameters measured by various sensors and instrumentation may be controlled by using control loops. A typical control loop consists of three basic component

  • Sensor: the sensor senses or measures process parameters and generate a feedback output acceptable to the controller.
  • Controller: the controller compares the measurement signal with the set value and produces a control signal to counteract any difference between the two signals.
  • System: Finally, the system receives the control signal produced by the controller and adjusts or alters the process by bringing the measured process property to return to the set point.

It is best to consider the controllability of a process at the early stage, rather than attempt to design a control system after the process plant has been developed to minimize the loss of resources.

It is well known that the food production processes are strongly non-linear, time-invariant, and often unstable. Automation of food production must handle these properties properly and employ them actively. It is a necessary step for generating the desired food structures, for inactivating and avoiding harmful chemical reactions which can lead to a substantial decrease in food quality.

The provision of the world population with food represents one of the most important future challenges for science and technology. In this context, many different objectives arise. In many countries of the world, the most urgent task is to satisfy the original nutritive minimum requirements. On the other hand, food has further functions in industrialized nations as the settlement of a special enjoyment or the promotion of health.

Any discussion regarding the automation of food production must distinguish the original production and the further treatment from the goal of preparing food for consumption, preservation, or refinement. For example, the original production of fish and sea animals take place predominantly in the oceans, those of fruit and vegetable in agricultural production centers. The automation in food production farms or centers differs fundamentally from such automation in factories. Nowadays to reach a larger market we need to ensure the safety and freshness of these items but with the manual process it takes a long time to sort and arrange the product and deliver them in time but with the help of control system or automated system these tasks complete with utmost efficiency & transparency.

  1. Importance of control systems in the food industry:
  • To maximize the benefit and for proper execution, we need digital control systems which save the organizations from costly failures in manufacturing.
  • As the demand increases day by day, food manufacturers have increasingly adopted computer-based systems for process control. This is primarily due to data accessibility y, application flexibility, and low cost provided by microprocessor technology to ensure adequate reliability.
  • Control system validation also ensures the proper operation of equipment under normal and abnormal conditions. Validation helps to assure product safety as well as the safety of manpower working in the factory.
  1. Guidelines and standards:

To ensure the correct action some guidelines & standards should be followed for the computer-controlled systems:

The FDA Perspective: DA defines validation as “the establishment of documented evidence, which provides a high degree of assurance that a specific process will consistently produce a product meeting its predetermined specifications and quality attributes” (FDA, 1987a). FDA promotes the concept of control system validation as a part of process validation within the food industry and has established some inspectional guidelines. which states that all food needs to be produced in such a way as to make sure that it has not been “prepared, packed, or held under insanitary conditions whereby it may have become contaminated with filth, or whereby it may have been rendered injurious to health.”

  1. Technology used:

Nowadays “big data” approach to the whole food supply chain (from farm to fork), would improve production efficiency and security and enable a new level of traceability in short, one of the most important lessons of the industrial revolution – the digital one – is that data is not a by-product, it is real added value and should be considered as the automation unique selling point. To cope with the extremely complex and variable scenario, a significant step-change in reducing food processing costs while increasing food quality and security is urgently needed. In this context, systematic use of automated & control systems with fully integrated digitized process control would facilitate a major advancement in food manufacturing efficiency, delivering significantly reduced production costs whilst lowering energy requirements and food waste.

  1. Reference:
  • “Feedback and control systems” – JJ Di Steffano, AR Stubberud, IJ Williams. Schaums outline series, McGraw-Hill 1967
  • Process Control in Food Processing Article by Keshavan Niranjan, Araya Ahromrit and Ahok S. Khare
  • Food Technology Article by SASHA V. ILYUKHIN, TIMOTHY A. HALEY, JOHN W. LARKIN Stanbury, P. F., Whitaker, A., Hall, S. J. 1995, Principles of Fermentation Technology
  • food manufacture 4.0 – automation and robotics at the service of food manufacturing article written by Andrea Paoli, Head of Food Manufacturing, Robotics and Automation at the National Centre for Food Manufacturing, University of Lincoln

Electrical Panels and It’s Types

  1. Introduction:

An Electrical panel is nothing but a load control Centre. All the electrical actions such as power distribution, transmission, power system protection is performed by using Electrical panel only. According to the NEC® definition, electrical panels are:

  • Used to control light, heat, or power circuits
  • Placed in a cabinet or cut-out box
  • Mounted in or against a wall
  • Accessible only from the front

Panels mainly consists of trip circuit, closing circuits, busbars, cables, MCCBs, MCBs, MPCBs, NO & NCs, etc. Electrical panels are ensuring the safe power distribution to the load. There are different ways in which electrical panels can be classified, from technologies and applications to capacity or even performance and safety but primary it is classified into two types:  HT (high tension) panels & LT (low tension panels).

  1. HT Panel:

HT Panels are generally used to supply power to various electrical devices and distribution boards. HT panels are installed both outdoor and indoor as well, while mostly used in substations for controlling the electricity flow. HT panels are designed to function at higher voltages (above 11 kilo Volts) with high insulation levels.

        HT panels include:

  • LBS Panels
  • VCB Panels
  • Metering panels
  • Load Break Switches
  • Vacuum Circuit Breakers
  • Ring Main Units (RMU)

  • LBS Panels: LBS panels are of a fixed type of switch having 3-poles and a spring-loaded shaft driving the moving contacts towards the fixed contacts. This is equipped with a trip-free mechanism for opening. LBS can be Tripped by hand push-button, shunt trip coil or a fuse-trip mechanism.
  • VCB Panels: A VCB panel is a type of circuit breaker where the arc quenching occurs in vacuum environment. VCB technology is ideal for medium voltage apps. Users can avail the technology for higher voltage, but it is not commercially viable.
  • Metering panels: Metering panels are a kind of control panels which are very much required for the domestic as well as industrial purposes for the measurement of amount of power used up and the rate of power consumption. These are best equipment’s which can easily be installed and can conveniently be used for the processes of power consumption.
  • Load Break Switches: A load break switch is a disconnectswitch that has been designed to provide making or breaking of specified currents. Load break switch comes with spring mechanism which are generally provided with Fuse protection. And hence, every time a fault occurs, fuse needs to be replaced.
  • Vacuum Circuit Breakers: Vacuum circuit breakers, the vacuum is used as the arc quenching medium. Vacuum offers the highest insulating strength. So it has far superior arc quenching properties than any other medium (oil in oil CB, SF6 in SF6 circuit breaker).
  • Ring Main Units (RMU): In an electrical power distributionsystem, a ring main unit (RMU) is a factory assembled, metal enclosed set of switchgear which are used at the load connection points of a ring-type distribution network. It includes in one unit two switches that can connect the load to either or both main conductors, and a fusible switch or circuit breaker and switch that feed a distribution transformer. Ring main units can be characterized by their type of insulationairoil or gas. The switch used to isolate the transformer can be a fusible switch or may be a circuit breaker using vacuum or gas-insulated interrupters. The unit may also include protective relays to operate the circuit breaker on a fault.
  1. LT Panels:

LT Panels are used with low tension cables to obtain power from the generator or transformer and distribute electricity to various electrical devices and distribution boards. LT panels are designed to function at lower voltages (up to 415 Volts) with low insulation levels.

      LT PANELS are classified into many types:

  • PCC (Power control center) Panel
  • MCC (Motor Control Center) Panel
  • APFC (Automatic power factor control) Panel
  • AMF (Automatic mains failure) Panel
  • DG Synchronization panel
  • Automation Panel (SCADA PLC Panel)


  • PCC Panel: PCC is a short form of Power Control Center. This is a heart of the control circuit. The output of the generators or transformers is given to PCC. It is also known as Main distribution board (MDB). Major protection circuits will be installed in this panel to protect transformers, Motors, Generators etc. The output Power from the PCC panel will be distributed to MCC panels via feeder.            
  • MCC Panel: MCC is a short form of Motor control center. It consists of Feeders. It’s an assembly to control some or all electric motors in a central location. It consists of multiple enclosed sections having a common power bus and with each section containing a combination starter, which in turn consists of motor starterfuses or circuit breaker, and power disconnect. A motor control center  also includes push buttons, indicator lights, variable-frequency drives(VFD), programmable logic controllers(PLC), and metering equipment. It may be combined with the electrical service entrance for the building
  • APFC Panel: APFC is an automatic power factor electrical device which is employed to boost the ability factor, whenever required, by switching ON and OFF the desired capacitor bank units automatically. APFC Panel has microcontroller based programmable controller which switches the capacitor banks of suitable capacity automatically in multiple stages by directly reading the reactive load (RKVA) which works in the principle of VAR sensing tends to keep up the PF to 0.99 Lag. 
  • AMF Panel: AMF Panel is the shortened form of Auto Mains Failure panel, it’s also be called an Automatic Transfer Switch. The AMF is connected to the incoming mains power supply & generator set to power control the operational functions. Once a power cut is detected, it automatically signals the generator to start and support the load. It will also start the generator if it detects that the mains power fluctuates. These are ‘out of pre-set tolerances’ instances, for example power dips. When the AMF panel detects that the mains has failed or is outside of tolerance, it will send a start signal to the generator to fire up & control the load.
  • DG Synchronization Panel: Basically DG Synchronization panel are mainly designed for meeting critical aspects of Power system requirements which primarily includes uninterrupted or flashing restoration of Power supply along with DG and circuitry protection for an infrastructure of social or  commercial  values and repute ( like Hospitals , Malls , Multi-storeyed residential societies, Hotels, Telecommunication sectors and  Industries with varied loads of power implementation ) D.G. Synchronization panels work both manually and with an automatic synchronizing function using PLC  for two or more generators or breakers. They are pre-dominantly used in electro-mechanical synchronizing of Diesel generators and provide multiplex solutions. 
  • Automation Panel: Automation panels combine the functions of a programmable controller and operator interface into a single unit. Automation panels reduce hardware costs by combining the controller, operator interface, and remote connectivity into one device. It may be more accurate to describe these panels as PAC controllers with a built-in operator interface, rather than just an operator interface that performs control. Nowadays it is more used in industry where the whole process is running with the automation & the control can be can remote. So, it minimizes the interference of humans.


Nowadays electrical panels are available in many different forms and sizes and is suitable for electrical enclosures in many kinds of buildings and establishments. They provide more security to all electrical components and parts and are fruitful towards effortless operations as well.

In industries, electrical consultants design electric distribution boards with a distribution transformer. After this, they bus duct this board to PCC Panel for more distribution of electrical panels. Also, electrical contractors supply MCC Panel and APFC Panel to enhance its functionality. Apart from this, when a client chooses to install a solar power plant, we supply Solar ACDB and Solar DCDB Feeder Pillar and Junction Box along with synchronizing panels.

And In process plant one or more motor control by a piece of equipment that called an electrical control panel. The electrical control panel starts or stops much equipment’s through switchgear and SCADA automation by using MCCB, Contractor, PLC, Overload relay and plug-in relay, etc.

Apart from all distribution panels there is one more panel called as solar panel which are used nowadays due to increase in the use of solar as the renewable energy source.

  1. Solar LT Panels:

Solar LT Panel is an electrical distribution board that receives power from solar panels and distributes the same to various electronic devices and distribution boards. These types of panels are used in industries both for internal as well as external use. Solar panels are used to collect solar energy from the sun and convert it into electricity.


The typical solar panel is composed of individual solar cells, each of which is made from layers of silicon, boron, and phosphorus. The boron layer provides the positive charge, the phosphorus layer provides the negative charge, and the silicon wafer acts as the semiconductor.


There are 4 major types of solar panels available on the market today:

  • Monocrystalline: monocrystalline panels can generate up to 300w of power capacity.
  • Polycrystalline:  polycrystalline panel is now capable of producing between 240-300w. However, monocrystalline panels still beat polycrystalline in terms of power capacity per cell.
  • PERC, and
  • thin-film panels.

  • Solar Panel Types Comparison sheet:

  1. Safety:

Always be cautious when working with any electrical panels. It has parts that can electrocute you and it can be lethal. Avoid touching the neutral bus bar, a neutral wire, main black cable, burnt or damaged parts, and exposed metal parts. Remember, it is only safe to touch a circuit breaker when all the power is turned Off. 

  1. Certification:

All Electrical control panel manufacturers should have CPRI Approved Label to design and manufacture premium quality electrical Panels. CPRI Approved means Central Power Research Institute established by the Government of India. CPRI approved manufacturers are professionals who are authorized by CPRI. The premier institute undertakes applied research in electrical functioning as an independent national testing and certification authority to manufacture electrical equipment. 

  1. Reference: