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What is the maximum ampere rating for a branch circuit breaker in QO load centers?<br />

Issue:
Application

Product Line:
QO LC

Cause:
Application

Resolution:
The maximum QO branch circuit breaker is 70 ampere (single pole), 200 ampere (two pole) and 100 ampere (three pole). Two pole QO breakers rated 150 - 200 ampere are restricted to Square D QO SINGLE PHASE load center, Series G1 (see Note #1), S1 or S2, rated 150 - 225 ampere or QON SINGLE PHASE load centers rated 300 - 400 ampere. The branch breaker ampacity cannot exceed the load center mains ampacity rating.
NOTE #1: Use only in Series G1 single phase load centers manufactured since 8/8/1986 (date code H08Sxxxx). The date code is stamped on the wiring diagram or box label. Also, the Interior Label located on the load centers interior assembly will list Type QOC breakers.
NOTE #2: In existing QON single phase, 300 - 400 ampere loadcenters, when mounted in MH50 or MH53 boxes and using MHC50VF or MHC50VS or MHC53VF or MHC53VS covers, the cover should be replaced with MHC50QVF or MHC50QVS or MHC53QVF or MHC53QVS, if over 10Kaic available. If mounted in MH68 box with MHC68VF or MHC68VS cover, no replacement cover would be required.



CTA-ID : 2022894
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