Grundfos MTD Series, Инструкция по установке и эксплуатации

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7. Fault finding the product
WARNING
Automatic startup
Death or serious personal injury
- Before starting work on the product,
make sure that the power supply has
been switched off and cannot
accidentally be switched on.
Fault Cause Remedy
1. The motor does not
run when the power
supply is switched
on. a) Supply failure. Connect the power supply.
b) The fuses are blown. Replace the fuses.
c) The motor-protective circuit
breaker has tripped.
Reactivate the motor protection.
d) The main contacts in the motor-
protective circuit breaker are not
making contact or the coil is faulty.
Replace the contacts or the magnetic
coil.
e) The control circuit is defective. Repair the control circuit.
f) The motor is defective. Replace the pump.
2. The motor-
protective circuit
breaker trips
immediately when
the power supply is
switched on. a) The fuse on one phase is blown. Replace the fuse.
b) The contacts in the motor-
protective circuit breaker are
faulty.
Replace the contacts in the motor-
protective circuit breaker.
c) The cable connection is loose or
faulty.
Fasten or replace the cable connection.
d) The motor winding is defective. Replace the pump.
e) The pump is mechanically blocked. Remove the mechanical blocking of the
pump.
f) The overload setting is too low. Set the motor-protective circuit breaker
correctly.
3. The motor-
protective circuit
breaker trips
occasionally. a) The overload setting is too low. Set the motor-protective circuit breaker
correctly.
b) Low voltage at peak times.
Check the power supply.
4. The motor-
protective circuit
breaker has not
tripped, but the
pump does not run. a) Check 1 a), b), d) and e).
5. The pump runs, but
gives no liquid or the
pump performance
is not constant. a) The pump inlet is partly blocked by
impurities.
Clean the inlet.
b) The liquid level in the tank is too
low.
Increase the liquid level.
c) The pump rotates in the wrong
direction. Change the direction of rotation of the
motor by switching any two of the
phases.
d) A lot of bubbles in the liquid. Check the operating conditions.
e) The piping systems are blocked or
have high resistance.
Check the piping system.
f) The impeller is damaged. Replace the impeller.
6. Noise and vibration
are high. a) A bearing is damaged. Replace the bearing.
b) The pump is running single phase. Check the electrical connection.
c) Some parts have come loose. Check the installation conditions.