Basic Trouble Shooting - LEGRAND DMX3 Series Manual

DMX

24. Basic trouble shooting

ACB does not close on pressing
"ON" button
Breaker can not be driven in
Test and Service position
ACB does not close electrically
ACB trips after closing
100
3
Situation Probability
U/V release is present but
not energized
Mechanism spring is not charged
Reset button ejected
Mechanical Interlock disables
closing
Breaker & Miss insertion device
ratings do not match
"Ready to close" (RTC) conditions
are not met
Overload fault exists if tripping is
after several seconds or minutes .
Other fault(s) exist if tripping is
within a second
Shunt Release is getting
command continuously
Solution
Energize U/V release
Charge the mechanism spring
manually till the spring status indi-
cator turns yellow
Press reset button
Re check before trying
to close the breaker
Put correct breaker
Check all RTC conditions
Check the unit protection and
identify the fault then clear
the cause
Check the source of command