What is an acceptable megger reading for QMB?
Issue:
Megger readings on QMB
Product Line:
QMB panelboard, switchboard with QMB distribution.
Environment:
Products sold in North America
Resolution:
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``.
Megger readings on QMB
Product Line:
QMB panelboard, switchboard with QMB distribution.
Environment:
Products sold in North America
Resolution:
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``.
Released for: Schneider Electric Canada
