ABB MNS R - Page 22

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1TTS900001M0902
OPERATION INSPECTIONS
1. Auxiliary circuits Power supply voltage absent Check the power circuit
according to the related diagram
and restore power supply
2. Indicator lamps Do not turn on • Checkandreplacethelamps
if necessary
• Checktheoperationofthe
signalling circuit apparatus by
means of the related diagram
3. Anticondensate heater Heating absent • Checkthethermostat
operation
• Checkthepowercircuit
4. Automatic controls (if installed) One or more function not carried
out
Search for the possible
cause and perform necessary
operations. If necessary, ask
ABB Sace
5. Devices and circuits for circuit breaker
remote control
Circuit breakers do not open or
close
Check the operation of the
controlgears and of the related
circuit (buttons, contacts,
fuses, power circuit protective
circuit breakers, terminal
tightening, relay contacts etc.)If
necessary, replace the damaged
components
6. Meters Irregular or absent indications • Checktheoperationofthe
meters with the checking
instrument
• Checktheoperationof
the voltage and/or current
transformer measuring circuit
7. Mechanical and electrical interlock
devices
Circuit breaker mechanical locking
device failure (key locks, anti-
introduction locks, different rated
current, etc.)
See the related instruction
manual
• Improperoperationofthe
external accept devices which
condition the switchboard
circuit breaker operations
• Failureofauxiliarycontacts
used for reciprocal interlocks
between the circuit breakers of
the same switchboard
Check the operation of the
related auxiliary circuits
according to the diagram. If
necessary, replace possible
faulty auxiliary contacts or
relays and check the terminal
connection of the auxiliary circuit
wires