URC UL Information


The Reality of UL Listing of Retrofit Kits on LVPCB (Low Voltage Power Circuit Breakers)

Importance of UL Listing

UL is a world recognized leader in product safety testing and certification. UL Listing is a valuable tool to facilitate acceptance of equipment. For a product to be UL Listed it must pass rigorous examination, testing and surveillance that demonstrate compliance with nationally recognized safety standards.

Requirements to be UL Listed

UL has a category that covers trip devices suitable for use in place of the original trip device of a LVPCB. This is UL Product Category PAYK.

The requirements for listing under Product Category PAYK are:
“The basic standard used to investigate products in this category is ANSI/IEEE C37.59, “IEEE Standard Requirements for Conversion of Power Switchgear Equipment”, which references ANSI/IEEE C37.13, “Low-Voltage AC Power Circuit Breakers Used in Enclosures”, ANSI/IEEE C37.17, “Trip Devices for AC and General Purpose DC Low Voltage Power Circuit Breakers”, ANSI/NEMA C37.50, “Switchgear Low Voltage AC Power Circuit Breakers Used in Enclosures”, and ANSI/UL 1066, “Low-Voltage AC and DC Power Circuit Breakers Used in Enclosures”.
[Reprinted from the Online Certifications Directory with permission from UL. © 2017 UL LLC]

Challenges of Required Testing

The main test for UL Product Category PAYK is a sequence of 3-Phase, fault interruptions at full voltage and at the maximum rated interrupting current of the breaker. Typically, 635V and up to 85KA.

The test setup consists of the breaker in its enclosure and a short circuit on the load side of the breaker.
The fault interruption test sequence is an “O-15S-CO” test. That is, the breaker starts out closed and then the voltage is applied causing a trip open “O”. Fifteen seconds later the breaker is closed into the same fault and the breaker trips open “CO”.

There are several challenges in performing the fault interruption testing required by the standards in UL Product Category PAYK.

The Challenges Are:

  • For most breaker types, used breakers must be utilized since new breakers are no longer available.
  • A high-power testing laboratory is required.
  • The test is very expensive.
  • Who offers UL Listed Retrofit Kits

    There are only two manufacturers listed under UL Product Category PAYK as shown below in the screen shot from the UL web site.

    Of the two manufacturers listed, Satin American Corp. no longer manufacturers retrofit kits for sale in the US and Canadian market.

    Utility Relay Co. (URC) with the AC-PRO, AC-PRO-II and AC-PRO-MP is the only existing manufacturer that offers UL Listed retrofit trip unit kits for legacy* LVPCBs.

    GE’s EntelliGuard retrofit kits are not UL Listed as suitable for use in place of the original trip devices in legacy* Low-Voltage AC Power Circuit Breakers.

    Eaton’s DigiTrip retrofit kits are not UL Listed as suitable for use in place of the original trip devices in legacy* Low-Voltage AC Power Circuit Breakers.

    Is Every Retrofit Kit Offered by URC UL Listed?

    No, not every AC-PRO or AC-PRO-II retrofit kit offered by URC is UL Listed.

    AC-PRO-II retrofit kits for the following breakers are UL Listed:
    DS-206, DS-416, DS-632, AKR-75, K-600, K-800, K-3000, LA-1600

    AC-PRO retrofit kits for the following breakers are UL Listed:
    DB-50, DS-206, DS-416, DS-632, AK-2-50, AK-2-75, KB Steel, K-600, K-800, K-1600, H-3 Series

    URC is periodically adding more breakers to the list of UL Listed trip unit retrofit kits. Contact URC for additional information.

    EntelliGuard is a trademark of the General Electric Company.
    * Our use of “legacy” breaker means a breaker that originally did not have an electronic trip unit or if it did have an electronic trip unit then the breaker was from a different manufacturer than the manufacturer of the retrofit trip unit.

    Have additional questions about our UL Certification?

    Our certification from UL can be found HERE

    The info contained on this webpage can be downloaded HERE.

     

    We are available to answer any additional question you have about our products or our certifications through our toll free number (888) 289-2864 or through email at URCSales@utilityrelay.com