NHP TemBreak PRO P - Page 49

Troubleshooting
49
TemBreak PRO P_BE-UM-001-EN V1.3.0
Problem description
Possible cause
Remedial advice
8
Nuisance tripping due to starting
current
Excessive inrush starting current
due to load type
Review INST and STD protection settings for load type where applicable
Switching operation of star-delta
motor starter, incorrect wiring
Verify and correct any issues with star-delta starter wiring with respect to the motor
windings and phase sequence. Refer to motor and/or starter manufacturer
Short-circuit in motor (e.g.
windings, starter circuit)
Verify and correct any issues with motor wiring. Inspect and verify motor winding
insulation. Refer to motor manufacturer
Erroneous connection of control
circuit for SHT or UVT
Verify control wiring and supply to SHT and UVT
9
No trip at pickup current
Failure in selectivity/coordination
with upstream circuit breaker or
fuse
Review selectivity/coordination study and protection parameters of each device
Incorrect protection settings
Review enabled protection settings ensuring correct pickup current and time-delay for
load type. (e.g. LTD, STD, INST pickup currents and time delays)