Standard 508A, Edition 3
UL 508A

Standard for Industrial Control Panels

UL CSDS Proposal Edition 3 Published Date: July 13, 2018 Last Revision: July 28, 2022

Summary of Topics b0508a_3_20180713_sum.html

Subject 508A

Bulletin Dated: July 13, 2018


The following changes in requirements to the Standard for Industrial Control Panels, UL 508A, are being proposed:

1. ECBT2 Connectors in Control Circuits

2. SCCR for EMI Filters in Panels

3. Use of Male-type Receptacles in Panels

4. Sizing of Branch Circuit Protection for Heater Loads

5. Emergency Stop Devices in Panels

6. Wire Positioning Devices in Panels

7. Sizing the Feeder: same approach for all Panels

8. Sizing the Feeder

9. Correct table 52.1 to allow markings to be in the inside of a panel

10. SB 4.3.3 - Addition of Class CFl

11. 55.4 Multiple Disconnect sign

12. Revision to Section 55 - Markings

13. Revision of 31.4.1(c) to correlate with NEC 430.53(C)(1)

14. Bus Bar Construction Requirements for 100kA SCCR without testing

15. Door interlocking / Restricted Access to Enclosures

16. Color Coding

17. Correction of 700A Class T fuse lethrough in Table SB4.2

18. Add UL 61010-2-201 to Par. Ex. 2

Back to Standard 508A, Edition 3

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