Operating instructions

NUISANCE TRIPPING OF INPUT CIRCUIT BREAKER
Some reports from field installations indicate that the 15 or 20 amp, single pole circuit breaker feeding main power to
the Mac Victor
®
Power Network (MVPN) will sometimes trip off upon startup of the POWERVAR UPM. In all cases,
factory testing has indicated that this problem is not associated with defects in the POWERVAR UPM. POWERVAR’s
investigation has revealed that when the MVPN is located in close proximity to the panelboard (approximately 10
feet), the current inrush caused by the initial start up of the UPM can trip the panelboard branch circuit breaker due to
high magnetic inrush even when it is not overloaded. The solution to this problem is to replace the circuit breaker with
one that can withstand the high magnetic inrush of the UPM startup.
TB-2
Listed below are the approved circuit breakers for various panelboard manufacturers that are designed to withstand
this high magnetic inrush.
Panelboard
Manufacturer: Part Numbers:
Square D QO-115-HM or QO-120-HM (snap on)
QOB-115-HM or QOB-120-HM (bolt on)
GE THQL1115HID or THQL1120HID (snap on)
THQB1115HID or THQB1120HID (bolt on)
Cutler Hammer HQP1015D or HQP1020D (snap on)
BAB1015D or BAB1020D (bolt on)
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