Mike Dolt Enterprises
Mike Dolt Enterprises
User: tedwards, Location: Lockport, IL
Asked on: Thursday, April 21, 2011 at 12:59 pm EDT
Answered on: Tuesday, May 14, 2024 at 4:29 am EDT
Question: I have a industrial control panel on site that is a UL-508A listed assembly. The electrical inspector came on site, opened the control panel and had some issues with wire sizing of some tap conductors inside the panel. Since the control panel is UL listed how can the inspector make me change wiring internal to the panel? How is this different than an electrical inspector coming into your home and tearing apart your clothes dryer saying that you need to make wiring changes to it?
UL-508A Listing and Its Scope
UL-508A is a safety standard for Industrial Control Panels. It covers the construction and testing of these panels to ensure their safety and reliability. However, it does not cover the internal wiring of components or subassemblies already certified by other recognized testing organizations (such as UL, CSA, etc.).
Authority of the Electrical Inspector
Electrical inspectors have the authority to enforce building codes and electrical safety regulations within their jurisdiction. This includes inspecting electrical equipment and installations to ensure compliance with the applicable codes and standards.
Inspector's Concerns with Internal Wiring
Despite the UL-508A listing, the electrical inspector may have concerns about internal tap conductor wiring if it: Violates the National Electrical Code (NEC) or other applicable standards. Poses a safety hazard due to improper sizing, insulation, or connection. Affects the performance or reliability of the panel.
Inspector's Actions
If the inspector identifies issues with the internal wiring, they may require the following actions: Provide documentation demonstrating that the wiring complies with the NEC or other recognized standards. Modify or replace the affected wiring to meet the inspector's requirements.
Difference from Home Appliance Inspections
Unlike appliances, industrial control panels are considered complex electrical systems. The inspector's primary concern is ensuring the safety and proper functioning of the equipment, even if it has a UL listing. This is because such panels can have potentially hazardous consequences if not installed or maintained properly.
Recommended Actions
To address the inspector's concerns, consider the following steps: Collaborate with the inspector to understand their specific requirements. Consult with the panel manufacturer or a qualified electrician to verify the wiring's compliance with relevant standards. Make necessary modifications or provide documentation as requested by the inspector.* Obtain a signed inspection report to document the changes or compliance. Flag for review