Standard 489A, Edition 1
UL 489A

Standard for Circuit Breakers for Use in Communications Equipment

UL Bulletin Edition 1 Published Date: June 01, 2012 Last Revision: June 26, 2023


Summary of Topics m0489_11_20120601_sum.html

Subject 489 (489A, 1066, 1077)

Bulletin Dated: June 1, 2012


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

1. Update on UL's 489 Ballot Opened 2012-01-06

2. Removal of Parts for Accessory Installation

3. New Requirements for the Use of DC Rated Circuit Breakers and/or Molded Case Switches in NEC Article 690 (Solar Photovoltaic Systems) Installations

4. Revised Requirements to Address Floating Screw Wiring Terminals

5. Optional Marking for Adjustable Trip Circuit Breakers with Ground Fault Element

6. Correction to Testing of 3-Pole Breakers for Use in Single Phase Circuits

7. Revised Requirements for the On/Off Marking

8. Clarification of Overvoltage Test Method - Undervoltage Trip Release

9. Addition of Requirements for Molded-Case Switches to Supplement SB

10. Clarification of Lock-Off and Lock-On Devices

11. Revisions for Table

12. Addition of Requirements for Class 2 Spacings

13. Revised Requirements for Wire Connectors

14. Revised Requirements for Insulating Materials

15. Addition of EMC Requirements in Supplements SF and SG

16. Update on UL 489B Including the Inclined Plane Tracking Test

17. Update on UL 489C

18. Update on UL 489D

19. Update on UL 1066

20. Editorial Corrections for UL 1077

21. UL 489B Test Samples

22. Neutral Pole

23. Photovoltaic (PV) Systems and UL 489B

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