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8. Troubleshooting
The following points must be taken into account to avoid personal and material damage
when troubleshooting machine failures:
Correct a failure only if you have qualified staff, i.e. the individual work must be carried out by
trained specialist personnel, e.g. electrical work must be carried out by a qualified electrician.
Always prevent the machine from unintentional restart by disconnection it from the power supply.
Take appropriate precautionary measures.
Ensure the safety shut-down of the machinery by a second person at all times.
Safeguard mobile machinery parts to prevent injuries.
Unauthorized changes on the machinery are at own risk and discharge the manufacturer from any
liability!
The machine does not start
Cause
Remedy
Interruption of the power supply, short circuit/short-
circuit to earth in the conduit and/or motor winding
Specialist to check conduit and motor and replace, if
appropriate
Trip fuses, circuit breakers and/or monitoring
devices
Connections to be checked by a specialist and changed, if
appropriate. Fit/set up circuit breaker and fuses according
to the technical instructions, reset monitoring devices.
Check impeller/propeller for smooth operation and
clean/restore to operability, if appropriate
The machinery starts, the circuit breaker is released, but is off shortly after start-up
Cause
Remedy
The thermal trigger on the circuit breaker is set
incorrectly
Specialist to compare the setting of the trigger with the
technical instructions and to correct if appropriate
Increased power input due to larger voltage drop
Specialist to check the voltage values of the individual
phases and change the connection, if appropriate
Impeller/propeller slowed down due to adhesions,
obstructions and/or solids, increased power input
Switch off machinery, secure against restart, restore to
operability of the impeller/propeller/clean suction branch
The medium is too thick
Contact the manufacturer
The machinery runs, but does not convey
Cause
Remedy
There is no pumped medium
Open inlet for container/gate valve
Inlet obstructed
Clean inlet, gate valve, suction piece, suction
branch/suction filter
Impeller/propeller blocked/slowed down
Switch off machinery, secure against restart, restore
operability of impeller/propeller
Defective tube/pipe
Replace defective parts
The machinery is running, the indicated operating values are not met
Cause
Remedy
Inlet obstructed
Clean inlet, gate valve, suction piece, suction
branch/suction filter
Gate valve in the pressure pipe closed
Open gate valve completely
Impeller/propeller blocked/slowed down
Switch off machinery, secure against restart, restore
operability of impeller/propeller
Air in the system
Check pipes, pressure mantle and/or part of pump, de-
aerate, if appropriate
The machinery conveys against too high pressure
Check the gate valve in the pressure pipe, open
completely if appropriate
Wear and tear
Replace worn parts
Defective tube/pipe
Replace defective parts
Inadmissible content of gas in the pumped medium
Contact the manufacturer
Dual phase operation
Specialist to check connection and to correct, if
appropriate
Too strong drawdown in operation mode
Check supply and capacity of the system, check settings
and function of the level control