DAB CM-G, Instruction For Installation And Maintenance

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ENGLISH
15
Fault Check (possible cause) Remedy
The motor does not start but makes
noise.

Ensure that the mains voltage
corresponds to the voltage on the
data plate.

Check that the connections have
been made correctly.
Correct any errors.

Check that all the phases are
present on the terminal board.
If not, restore the missing phase.

The shaft is blocked. Look for
possible obstructions in the pump
or motor.
Remove any obstructions.

Capacitor short-circuiting or
broken.
Change the capacitor.
The motor turns with difficulty.

Check the supply voltage which
may be insufficient.

Check whether any moving parts
are scraping against fixed parts.
Eliminate the cause of the scraping.

Check the state of the bearings.
Change any worn bearings.
The (external) motor protection trips
immediately after starting
.

Check that all the phases are
present on the terminal board (on
three-phase models).
If not, restore the missing phase.

Look for possible open or dirty
contacts in the protection.
Change or clean the component
concerned.

Look for possible faulty insulation
of the motor, checking the phase
resistance and insulation to earth.
Change the motor casing with the
stator or reset any cables
discharging to earth.
The motor protection trips too
frequently.

Ensure that the environment
temperature is not too high.
Provide suitable ventilation in the
environment where the pump is
installed.

Check the calibration of the
protection.
Calibrate at a current value suitable
for the motor absorption at full load.

Check the motor rotation speed.
Consult the motor data plate.

Check the state of the bearings.
Change any worn bearings.
The pump vibrates and operates
noisily.

Check that the pump and/or the
pipes are firmly anchored.
Fasten any loose parts.

There is cavitation in the pump.
Increase the system pressure,
keeping within the allowed limits.

The pump is running above its
plate characteristics.
Reduce the flow rate.

Ensure that the mains voltage
corresponds to the voltage on the
data plate.
The absorbed current is too high.

Check that the fluid density or
viscosity is not too high.
Analyse the fluid to be pumped.

Check whether any moving parts
are scraping against fixed parts.
Eliminate the cause of the scraping.

The feeding voltage is not the
same as the voltage on the data
plate.
Feed the motor with the correct
voltage.

The pump is running above its
plate characteristics.
Reduce the flow rate.