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What is an acceptable megger reading for QMB?

What is a acceptable megger reading for QMB?
Product Line:
QMB panelboard, switchboard with QMB distribution.
Products sold and used in the United States.
UL standards do not specify an acceptable megger reading. UL standards require a dielectric voltage withstand test be conducted at twice rated voltage plus 1000V for one minute ( phase to phase and phase to ground).

NEMA standard PB1.1, section 7.4 says a reading of less than 1 meg ohm should be investigated as a possible `` unsafe condition``.

CTA-ID : 2020078
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