Products & Solutions

UL 508 Listed Industrial Cable Assemblies

First and only manufacturer to offer both listed and recognized options for uses in UL 508 applications.

Learn about UL and Best Practices

What is UL 508A?

UL 508A is a standard that dictates the design of some electrical cabinets. Those who build cabinets that adhere to this standard are limited to the components listed in the standard. If they want to use additional components, the onus to prove their safety is on the cabinet builder. HARTING worked with UL to test and certify HARTING connectors for use in UL 508A electrical cabinets without requiring additional testing. 

An Industry First: Individual HARTING connectors eligible for UL 508-certified Control Cabinets

HARTING has achieved a breakthrough that facilitates the use of connectors and connector-based cable assemblies in electrical control panels, switchgear and other control systems requiring UL 508 certification.
More than two dozen HARTING connector configurations have passed rigorous safety testing by UL and been designated “UL-Recognized”, a newly created approval in the 2237 category. This approval was put in place by UL at the request of HARTING.

UL 508 Interview

HARTING is the only UL Recognized connector manufacturer with products that have earned this status and corresponding UL mark. Users gain access to all the benefits of Plug & Play connectorization in panel assembly, including massive cost and time savings during commissioning and maintenance compared to the alternative – hard-wired connections.

Fast track end product certification with UL approved HARTING connectors

Until now, an OEM could not use individual connectors in a field-assembled, UL 508-certified control cabinet unless it subjected the end product to extensive additional UL safety testing at its own expense, a time-consuming process that often delays bringing a new machine to market. Using UL-Recognized components from HARTING simplifies and fast tracks end product certification, providing specific conditions in the use of the connectors are followed. There is a UL-Recognized HARTING connector product for almost any control panel application. All are well-proven catalogue products, employed in a wide range of applications, including control cabinets certified to other international standards. HARTING will seek UL-Recognized status for many more of its connectors in the months and years to come.

Additionally, HARTING will launch an extensive range of “UL-Listed”, pre-assembled standard cable assemblies made with UL-Recognized connectors. UL-Listed wire assemblies may be employed in UL 508-certified control cabinets without any additional testing or other conditions.

If You're New to UL 508A Start Here

What is UL?

UL (Underwriters Laboratory) is a safety consultation and certification company that develops safety standards for electrical devices and components.  This is done through testing, validation, and inspecting. They also provide auditing, advising, and training services.

Essentially, a UL certification is a guarantee of the safety of a product and is evidence of third party certification 

What is UL 508?

UL 508 (508A and 508C) is a standard for electrical control cabinets and switchgear. It ensures machine builders and their customers (as well as regulators and insurers) that the cabinet can be operated reliably and, most importantly, safely. Globally, it is not the only standard covering control cabinet safety, but is the one most often used in North America.

When is UL 508A needed?

The need for UL 508 compliance is often dictated by the needs of the end customer.  A UL certification is a safety and reliability guarantee to the end customer so some will only use UL 508 certified cabinets in their facilities.

For a control panel to carry the UL mark only UL-recognized and listed components can be used in the cabinet.  Manufacturers that carry a UL 508A Listing Mark are subject to unannounced inspections by UL. This auditing process ensures that the manufacturer continues to meet certification requirements. 
The UL 508 label certifies that the panel meets the UL 508 safety standard and was produced by a UL Listed Panel Shop. 

Where does HARTING fit into the UL 508A Standard?

HARTING has created two possibilities for using its industrial connectors to make electrical connections in UL 508 control panels, switchgear and other control systems. The first is the creation of an extensive range of “UL-Listed”, pre-assembled, connector-based cable assemblies that meet the requirements of UL 2237 (“PVVA” section), a complementary standard to UL 508 that governs multi-point connections of power cables in industrial machinery. 

The second is made possible through the newly launched “PVVA2” section of UL 2237, which was established by UL at the request of HARTING. It allows for field assembly using individual “UL-Recognized” components. The PVVA2 classification facilitates the use of connectors in a UL 508-certified cabinet, which in turn will deliver benefits throughout all stages of product design, fabrication, testing and commissioning, with enormous time and cost savings over hard-wired connections. HARTING connectors are the only rectangle connectors that have undergone rigorous testing by UL to gain “ULRecognized” (PVVA2) status, which also makes them suitable for incorporation in PVVA cable assemblies. A wide range of HARTING connectors now have “UL-Recognized” status, and many more HARTING products will be added to both the PVVA and PVVA2 lists in the months and years to come.

UL 508A - Best Practices

Building a UL 508 cabinet requires a lot of planning.  Below are some best practices for developing a UL 508 cabinet.

Familiarize Yourself With the UL 508 Standard

If this is the first time you’ve built a UL 508 cabinet, you will have a lot to do to ensure compliance.  The best place to start is the UL 508 website.  The entire UL 508 standard is available for purchase here.

Also listed are standards that are referenced by UL 508, such as UL 2237 the standard under which UL listed HARTING components fall.

Select all the physical components you will need and layout your cabinet:

1. Look at your customer specifications and select the right enclosure and components to meet them.

2. Develop layout drawings with all the components to ensure they fit.

3. Develop wiring schematic drawings for components.

4. Order the selected components and enclosure to determine the earliest production start date.

Coordinate wire sizes and component types

Base your wires size on load current and circuit protection on wire size.  Wire size determines how the current load(s?); while the correct circuit protection insures high load current prevents overheating, which poses a fire hazard. 

Select components based on voltage and load current and component type based on function. Component size dictates voltage and load current possibility; component type determines functionality.

Choose the Best Control Type for Your Needs

As a general rule of thumb, you should start with simple components (such as relays and timers) and move to components with more complex functionalities (like programmable Smart Relays or Programmable Logic controllers [PLCs].  Complex controls provide significantly more functionality(;) also significant programming time.

How to Choose the Best Operator Device Type for Your Needs

Again, always start with simple operator devices (Pushbuttons, Pilot Lights, Digital Panel Meters, etc.). More complex solutions, such as a color touch screen display as the Human Machine Interface (HMI) can be added as needed. This provides significantly more functionality, but it also requires a computer and programming software and someone who knows how to use the software to program the desired functionality.

Use UL to Pick the Right Components:

UL lists, to the manufacturer’s part number, components that have been certified.  Using the referenced standards to UL 508 (as listed on their website) fast-tracks your design for UL 508 certification. 

Best in class suppliers will make it easy for you to find the parts that you need.  For example, all of HARTING’s part numbers can be found on our UL 508 website.  Such documents include: