Industrial control panels play crucial roles in many manufacturing companies, although manufacturing isn’t the only industry that utilizes them. Control panel builders must follow strict rules and regulations when designing industrial control panels. One of them is the Underwriter’s Laboratories UL508A. Continue reading for tips on implementing UL508A standards in control panels and a closer look at their benefits.

What Is an Industrial Control Panel?

An industrial control panel (ICP) is an electrical components collection used to control and monitor industrial devices in industrial applications. They consist of circuit breakers, timers, switches, overload relays, pilot lights, surge suppressors, pushbutton stations, motor controllers, and others.

According to Underwriters Laboratories (UL), the official definition is that an ICP is the assembly of two or more industrial control equipment pieces.

UL508A Standards for Industrial Control Panels

The UL in UL508A stands for Underwriters Laboratories, as previously discussed. It’s an independent, non-profit organization based in the United States. They test and certify products and components for safety. They’re the largest non-profit testing lab in the world and work with various stakeholders, such as manufacturers, governments, regulatory bodies, and other supply chain parties.

UL provides product manufacturers and other organizations with a spectrum of conformity and quality assessments. They provide inspections, auditing and training services, testing, and inspections to retailers, regulators, policymakers, consumers, manufacturers, and service companies. They also evaluate the sustainability of products and their environmental impact.

UL508A sets the standard for industrial control panel designs. It helps companies understand how to put the control panel together and holds each panel to the same standards. The National Electrical Code (NEC) accepts and recognizes the UL requirements. The UL508A also conforms to the NEC, which translates to a safer and high-quality control panel.


There are three designated classifications that UL assigns to products that pass testing. Here’s what the different classifications mean:

  • UL Listed: The product meets the laboratory requirements and is usable.
  • UL Recognized: UL assigns this classification to components combined with other elements to make the final product.
  • UL Certified: This product meets the UL and other standards, such as ones set by authorities for building code or electrical requirements.

Any product that passes the UL testing receives a sticker. Each sticker varies depending on which country you’re in. You’ll see the mark alongside others, like FCC, RoHS, CE, and more.

UL Importance

UL certification demonstrates competency to service providers. Consumers and facilities want to know they hired a qualified business to install their equipment. Plus, they want to ensure that all the equipment and devices used have gotten tested and meet industry and safety standards.

Companies show they meet all federal and local standards through UL certification. It provides peace of mind for customers and employees.

Important Reminder

A panel may carry the UL marking, but that doesn’t mean the complete industrial control panel has undergone testing. It means the electrical components, construction, and panel meet the UL508A requirements. UL also has standards for all enclosure coverings, such as:

  • Bonding
  • Enclosure openings
  • Field wiring
  • Markings
  • Disconnect switches
  • Ventilation openings
  • Enclosure of environmental control devices
  • Internal wiring

Benefits of UL508A Control Panels

There are plenty of advantages to choosing a UL508A industrial control panel. What do these benefits include? One of them is third-party certification. A UL marking signifies that the equipment has third-party certification. All the components and manufacturing techniques meet the highest standards for industrial control panels.

Another benefit is proper labeling. Installers will follow strict labeling requirements. Every UL508A control panel will have the same construction technique. Technicians will use the correct torque settings for cables and wires.

Using UL-certified parts will make it easier to find replacement components when the time comes. The last benefit is that all short-circuit current ratings (SCCR) will have the correct calculations. Technical ratings and proper labeling verify met requirements and limit risks.

Navigating UL508A Advice

Most panel builders don’t place the UL508A compliance focus on individual panel parts because it guides the builders regarding where to place each component. Two guidance documents help the builders select the panel parts. They are the UL Supplement SB and the UL Supplement SA. The SB gives direction on SCCR assembly calculations. The SA specifies standards for control panel components.

Consider installing overcurrent protective devices with high interruptive ratings to ensure a high SCCR. Your panel’s SCCR will never exceed the lowest interrupting rate. Correctly applied current-limiting devices, such as fuses, used with feeder circuits can increase a branch circuit’s SCCR. Using feeder and branch components with high-fault SCCRs will help improve the short circuit current rating overall.

Industrial Control Panel Design Basics

The basics of industrial control panels are simple to grasp. Several considerations include operator controls, attractive appearance, cost, and reliable operation. The simple design allows for low maintenance and easy panel control operations.

Your thoughts and design may seem unorganized as you jot them down on paper. Outlining the physical characteristics will help you eliminate potential issues. What components should the drawing outline? Include a functional diagram, power distribution network, the bill of materials, input/output layout, and control cabinet and back panel layouts.

A clear table of contents provides a foundation for the development process of the panel. It’s not as simple as choosing the right back panel and enclosure. The machine requires proper wiring and adequately integrated equipment.

After Planning and Building the Industrial Control Panel

As the client, you have a few options. You can contact UL’s Field Evaluation Services and report the situation. You’ll want to schedule a field visit evaluation. Understand this will cost you money. You can also contact a local UL508A shop to ask if they’ll evaluate the industrial control panel. They’ll inform you if work still needs to get done to meet the UL requirements. The cost of this option could be less than the first one. Use the list of Electrical Control Panel Builders to find the right electrical control panel fabrication service provider near you.

Xpect Solutions designs and fabricates control panels to meet UL508A standards. We implement these requirements so our clients don’t have to worry. You’ll be working with a leading provider in the industry when you choose Xpect Solutions. We focus on quality and efficiency with every design, and we’ll work closely with our customers to create the ideal industrial control panel.

Tips for Implementing UL508A Standards in Control Panels