How to write better electrical specifications for food manufacturing equipment

Growing companies have an electrical specifications list that isn’t robust enough to be practical when scaling up manufacturing equipment.

By Michael McCollum February 10, 2023
Courtesy: Chris Vavra, CFE Media

Electrical specifications insights

  • New companies don’t often have proper electrical specifications in place.
  • Some factors that impact the effectiveness of electrical specifications are hardware brands, communication protocols and more.

There are certain performance expectations food processing equipment should meet to maximize return on investment (ROI). Failing to establish and standardize equipment electrical specifications (specs) during the procurement process can directly impact a plant’s safety, sanitation, efficiency and profitability. Many companies might have a plan, but they often have room to improve.

Often, growing companies will have a simple specifications list that isn’t robust enough to be practical when scaling up or building a brand-new production line or food plant. Other times, their existing equipment specifications list may underperform because it was developed years ago and hasn’t been updated to reflect the latest technology or government regulations. The list goes on.

Many factors must be addressed while developing an equipment specifications list for vendors. In this blog post, we’ll focus on electrical specifications, an often overlooked area that can completely derail a project when done incorrectly.

Nine factors that impact the effectiveness of electrical specifications

1. Hardware brands

As food manufacturers incorporate more complex automation into their facilities, it’s a good practice to standardize the hardware throughout their process areas. Specifying a particular brand of hardware will simplify maintenance, mitigate the risk of operator error and reduce the number of controls and spare parts needed for individual processing lines.

For example, if users mix and match American hardware protocols and European hardware protocols in a plant, they’ll need to find a maintenance team that can safely perform work on both or hire additional qualified personnel for the separate hardware. Some original equipment manufacturers (OEMs) may charge extra to adopt standards, such as a German OEM that typically uses Siemens hardware. In my experience, it’s often worthwhile to specify standard platform upfront.

2. Communication protocols

Each facility has its own manufacturing execution system (MES) that tracks and analyzes production data to provide real-time insight into production metrics, line status and inventory.  Integrating multiple systems to automate a line becomes more complex when individual pieces of equipment are manufactured using different platforms. Sending OEMs the standardized communication protocols during the bid process can lead to a smoother product handoff and faster startup.

3. Programmable logic controllers (PLCs)

A common mistake I see in facilities is mismatched or outdated programmable logic controllers (PLCs) between different pieces of equipment. This is less important if the components don’t interact, but since the PLC is the “brain” of automation equipment, it can lead to failure in interconnected lines.

While it’s possible to integrate a line with different PLCs, it’s certainly easier and quicker if all equipment is manufactured using the same communication protocols. Consider a facility with a line that includes a weighing system, packaging machine and palletizing system. All three pieces of equipment must have communication wiring connecting them to streamline product handoff, report faults and automatically start or stop a line depending on the analyzed conditions. A communication error at any point can cause a stop in production. Also, troubleshooting errors becomes more difficult when trying to interface between different PLCs, such as Allen Bradley and Siemens PLCs.

It can also get expensive to resolve issues between equipment with different hardware. In one project I worked on, we solved interlocking communications between two pieces of equipment by adding a secondary PLC on the upstream equipment that matched the downstream equipment on the line, with the sole job of translating I/O from one communication protocol to the other to enable automatic start/stop functionality and error reporting. Before that upgrade, each piece of equipment operated standalone and required manual reset and restart of the line. This solution cost the owners thousands of dollars in hardware alone, not to mention the downtime due to programming and debugging the upgraded system.

4. Human-machine interface (HMI) configurations

Owners can design their plant’s HMI configurations to reflect a variety of preferences. For example, do they want a low-performance controller that is PC-based or an advanced HMI controlled by the PLC? Maybe somewhere in between fits the budget.

Regardless of the final selection, standardizing HMI configurations will ease operation for plant personnel and prevent disruptions in production. For instance, I’ve worked with facilities that use multiple programming laptops with different versions of Windows and programming software to support their legacy equipment alongside the more modern equipment. Imagine if the maintenance team has to troubleshoot six different types of HMI software. That will only extend downtime while the manufacturer sorts through the appropriate protocols.

5. The specific food plant environment

The environment impacts both how equipment is manufactured and how much it will cost. The specifications should clearly distinguish the different areas within the plant to prevent incompatibility issues and sticker shock.

For example, non-washdown areas typically have cheaper requirements than ready-to-eat processing areas where equipment and control panels are exposed to vigorous sanitation procedures. The electrical specifications for equipment and installation should clearly define the materials and methods of construction to suit the environment, including the National Electrical Manufacturers Association (NEMA) or IP6X level of the panels, standoff supports for conduit and shields for HMIs.

6. Evolving technologies

It’s important to avoid getting gridlocked in the “We’ve always done it this way” mentality. Technology evolves rapidly in the food manufacturing industry and even more quickly in the world of electrical controls and automation. As companies are developing or updating the specifications, invest time researching current best practices and the latest advancements.

I highly recommend working with an experienced system integrator who can help identify opportunities to improve the overall equipment effectiveness (OEE) of the machinery and processing lines. For example, a knowledgeable partner might recommend additional automation opportunities or updating the control system in the equipment to a faster processor with advanced data collection capabilities.

7. Facility age and project scope

If companies are building a brand-new facility, they have the opportunity to integrate the best of the best into the specifications. Upgrading or expanding an existing facility requires additional legwork — and may require more capital investment. First, identify the current specifications used in the facility. Depending on the setup and age of the system and the size of the project, it may be more cost-effective long term to upgrade the entire facility to the latest technology.

An outdated system could drive up the cost of working with an OEM. Consider a facility’s plant network that uses technology from 1999 and doesn’t have ethernet capabilities. Companies wouldn’t specify that each OEM needs to provide an Ethernet switch, but that missing component may require the OEM to use legacy protocols. Owners often pay a premium for the OEM to source legacy control hardware and integrate it because it’s a custom job. At some point, the system will also become so outdated that parts will be unavailable altogether. Evaluate opportunities and upgrade to keep up with the competition.

8. The level of detail

Specifications provide a standardized measure for quality control in the facility — but only if done correctly. Vague, unclear and/or incomplete specifications can reduce their effectiveness and significantly delay the procurement, purchase and installation process.

An OEM or electrical contractor responding to a request for proposals (RFP) with ambiguous specifications may fill in the blanks using their own standards, which are not guaranteed to match the desired caliber. Did they give the low bid because they cut a few corners? This can affect equipment efficiency, reliability and function, sanitary conditions and even require rework in the event of a failed system integration.

9. OSHA and NFPA requirements

Make sure the specifications require compliance with the latest versions of all applicable codes and regulations. The Occupational Safety and Health Administration (OSHA) and National Fire Protection Association (NFPA) adjust their requirements yearly to reflect the latest safety standards. Ensure the specifications don’t hinder compliance, especially in older facilities. Pay close attention to ingress and egress codes, since they change often. NFPA 70 covers the National Electrical Code (NEC), which is the benchmark for safe electrical design and installation.

Working with a qualified partner for electrical specifications

Lean on a knowledgeable partner throughout this process. There are a myriad of factors to consider when developing and reviewing your specs list. The last thing you want is to overlook a detail that could create challenges and delays for a company’s personnel and operation.

Stellar is a CFE Media and Technology content partner.

Original content can be found at Stellar.

Author Bio: Michael McCollum is a project engineer in manufacturing. He is experienced in project management, sanitary process design, piping system construction and CAD software. Michael has eight years of industry experience, including more than three years with Stellar.