NMFIRE NFPA20 - 6.0 TROUBLE SHOOTING; 6.1 Electric motor pump

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6.0 TROUBLE SHOOTING
6.1 Electric motor pump
Trouble
Possible causes
Remedy
1. Motor does not run when
started
a) No power connection.
Connect power supply.
b) Blown fuse.
Replace fuse.
c) Motor starter overload
protection has failed.
Repair motor protector.
d) Thermal protector
protection failed.
Repair thermal protector.
e) The main contactor of the
motor starter is not
connected or the
electromagnetic coil is
discontinuous.
Replace the contactor or
electromagnetic coil.
f) Control circuit damaged.
Repair control circuit.
g) Motor damaged.
Repair motor.
2. When the power is
connected, the motor starter
overloads and fails
a) Fuse/automatic control
circuit broken.
Replace fuse.
b) Motor starter contact
switch overload failure.
Replace the contact switch
of motor starter.
c) Loose or defective
connection wire.
Tighten or replace the
connection wires.
d) Motor coil damaged.
Repair motor.
e) The pump is mechanically
blocked.
Clear up the blocked.
f) Overload setting too low.
Set up motor starter
reasonably.
3. The motor starter
occasionally jumps off
a) Overload setting too low.
Set up motor starter
reasonably.
b) The voltage is too low
during the peak period.
Check the power supply.
4. The motor starter starts
normally, but the pump does
not run
a) No power connection.
Connect the power supply.
b) Blown fuse.
Repair fuse.
c) Thermal protector
protection failed.
Repair thermal protector.
d) Control circuit damaged.
Repair control circuit.