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Do You Know if Your ICP Requires More than a Standard UL 508A Listed Mark? - George T. Hall Company

Written by Dana-Beth Farris | Mar 24, 2022 3:24:18 PM

Whether you need to control a wastewater treatment plant, pharmaceutical production equipment, or oil and gas operations, safe process control is essential to protect your personnel and control system equipment. A widely recognized way to ensure safe process operations is to work with a UL Certified Panel Shop to build your industrial control panel (ICP) to the appropriate UL standard for your application.

While UL 508A is most often followed UL standard since it is the baseline standard for panels used in ordinary locations, there are supplemental standards in place for panels that need to be used in hazardous locations or in an area relating to a hazardous location. More specifically, if an ICP needs to incorporate intrinsic safety barriers to connect to circuits residing in hazardous locations, the panel will need to follow the additional guidelines set by UL 698A.

To receive a UL marking for an application that requires compliance with UL 698A, there are additional considerations and requirements that must be met beyond what is needed for the general UL 508A safety standard. At a high-level, some of these requirements include the following:

  • Using UL Listed Components including switches, terminal blocks, contactors, motor drives, transformers, overcurrent protective devices, and, for UL 698A specifically, intrinsically safe devices.
  • Meeting design requirements for how the power is distributed through intrinsically safe barriers to field devices located in classified areas.
  • Adhering to spacing requirements within the panel and meeting defined overload and overcurrent protections.
  • Ensuring all field circuits entering the classified location operate at a low voltage and current and that proper labeling is used on the circuits.
  • Following spacing requirements within the panel to use a minimum of 6 mm of spacing between the connection terminals for field wiring of different intrinsically safe circuits.
  • Meeting overload and overcurrent protection requirements, including requirements for any ground terminals for intrinsically safe barriers.
  • Providing detailed panel control documents to ensure the proper installation of intrinsically safe devices.

Meet UL 698A Requirements by Working with the Right Panel Build Partner

At George T. Hall (GTH), our engineers have extensive experience developing both UL 508A and UL 698A Listed panels. We also know exactly when the panel needs to go beyond following the standard UL 508A guidelines to comply with UL 698A requirements. We are a UL Certified Panel Shop which means we have the necessary certifications and staff to build panels that we can apply the UL Listed Mark to ourselves. We do not need third-party inspections, which saves time and money for our panel build customers. With every panel we build, we focus on product quality and safety, and our technical personnel have in-depth knowledge of these industry standards, ensuring every phase of the process, from system design to start-up, is seamless.

Learn more about UL 698A and our process to building ICPs that will receive the UL Listing you need in our new white paper, Going Beyond the UL 508A Safety Standard: Understanding when an Industrial Control Panel Needs to Comply with UL 698A.