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Standard 1778, Edition 5

Uninterruptible Power Systems

UL Red Line
Standard 1778, Edition 5 Edition Date: October 10, 2017
Summary of Topics s1778_5_sum.html

Summary of Topics

This revision of ANSI/UL 1778 is being issued to include the following changes:

Addition of dated reference to UL 60950 RD

Update to references to the component requirements of the RD

Update to Table for temperature limits

Revision to bus bar temperature limits

Addition of symbol for no telecommunication network

Corrections in Annex NNN for short-circuit withstand rating

Addition of requirements and figure for short circuit withstand and short circuit closing test port location

Updates to References

Back to Standard 1778, Edition 5

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