1 Scope

1.1 This standard applies to the following types of transfer switches that have a maximum rating of 1000 volts for use in non-hazardous locations, in accordance with Annex A1, Item 1:

1. a) Automatic transfer switches;

2. b) Manual or non-automatic transfer switches;

3. c) Closed transition transfer switches;

4. d) Hybrid transfer switches;

5. e) Transfer switches for fire pumps;

6. f) Bypass/isolating switches;

7. g) Softload transfer switches;

8. h) Transfer switches intended for use as service equipment;

9. i) Transfer switches intended for use in mobile/portable applications such as recreational vehicles, motor homes, camping trailers, and mobile health care facilities;

10. j) Inlet assemblies for transfer switch equipment;

11. k) Arc resistant transfer switch equipment;

12. l) Cord connected transfer switch equipment;

13. m) Combination meter/transfer equipment assemblies; and

14. n) In Mexico and the United States, branch circuit emergency lighting transfer switches (BCELTS).

15. In Canada, the requirements for BCELTS do not apply.

Summary of Topics

This revision of ANSI/UL 1008 is being issued to incorporate the following changes:

Revision to Add Recreational Vehicle Transfer Switches to the Scope of UL 1008

Revisions to Address the Grounding and Bonding of Neutral Circuits

Revision to the Overload, Endurance, and Short Circuit Testing

Miscellaneous Revisions Regarding Inlet Assemblies, Mechanical Interlocking of Single Pole Inlets and Readily Accessible Service Disconnect Switches

Revisions Regarding the Use of "Circuit Breaker Based" Transfer Switches and Compliance with Service Disconnecting Requirements

Revision for Consistency with UL 50E Rain Test

Revisions to Annex E to Cover Freestanding Complete Packaged Fire Pump Power Transfer Units

Revisions to Address System Available Fault Calculations for Momentary Paralleling Situations

Clarification of Marking Requirements

Revised Requirements for Monitoring the Temperature on Inlets