Standard 489A, Edition 1
UL 489A

Standard for Circuit Breakers for Use in Communications Equipment

UL Bulletin Edition 1 Published Date: July 24, 2014 Last Revision: June 26, 2023


Summary of Topics m0489_12_20140724_sum.html

Subject 489 (489A, 1066, 1077)

Bulletin Dated: July 24, 2014


The following topics were discussed at the meeting of the Standards Technical Panel for Molded-Case Circuit Breakers, Molded-Case Switches, and Supplementary Protectors, STP 489:

UL 489

1. Addition of Requirements for the Use of 90°C (194°F) Wire with Molded-Case Switches

2. Revision to Requirements for the Calibration Testing for DC Circuit Breakers

3. Revision of Requirements to Reference Supplement SE

4. Clarification of Requirements for Interchangeable Trip Units

5. Addition of Three-Pole Tests to Table 7.5.4

6A. Revision of Requirements for the Temperature Measurement in Clause

6B. Revision of Requirements for the Temperature Measurement in Clause

7. Clarification to 7.10.3

8. Addition to Temperature Test Requirements

9. Clarification of Requirements for Series-Connected Circuit Breakers

10. Revisions to Address DC Rated Circuit Breakers

11. Revision of HACR Marking to be Optional

12. Addition of Calibration for Circuit Breakers employing AFCI, GFCI, and EGFP

13. Additional Slash Ratings For Handle Tied Breakers

14. Electronic Trip Circuit Breakers and 100 Percent Calibration at 40°C

15. Revision to Table 7.5.4 Regarding the GFPE Interrupting Operations

16A. UL 1699C, Proposed Standard for System Combination Arc-Fault Circuit Protection

16B. Addition of Unwanted Tripping Tests

17A. Motor Protection Circuit Breakers

17B. Motor Protection Circuit Breakers

18. Clarification on the Use of 3-Pole Breakers for Use in Single-Phase Circuits and Wye Systems

19. Circuit Breaker with Dependent Manual Operation

20. Verbiage to Test the 15A Rating

21. "Degree Sign" Marking Requirement for Wire Type

22. DC Shunt Resistance

23. Clarification of Solid/Stranded Requirement Only Required for 14 - 10 AWG

24. Reliability of Solid State Components in Electronic Trip Units

25. Expanding the Scope of UL 489 to 1000 Vac/1500 Vdc

26. Addition of Requirements for Thermal Memory Retention

27. Addition of Requirements for Self -Protect Function for Electronic Trip Units

UL 1077

28. Field Wiring Terminals for Supplementary Protectors

29. Other Protective Type Devices

30. Overvoltage Testing

31. Correction to Figures 21.1 and 25.1

32. Test Conductor Length

33. DC Rated Protectors with Poles Wired in Series

34. UL 489 and Strain Relief Requirements

35. New Requirements for Arc Energy Reduction

36. New Proposed Standard for Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit-Breaker Enclosures for Use with Photovoltaic (PV) Systems, UL 489B

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