Xylem LOWARA e-SV Series, Инструкция по установке, эксплуатации и обслуживанию

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en - Original instructions
34 e-SV series - Installation, Operation and Maintenance Manual
7.4 The thermal overload protection triggers or the fuses trip
The motor thermal overload protection triggers or the fuses trip when the unit starts.
Cause Remedy
It is calibrated at a value too low in relation to
the rated current of the motor Recalibrate
Missing power supply phase Check the power supply and restore the phase
Loose and/or faulty connections of the thermal
overload protection Tighten or replace the clamps and terminals
Loose and/or incorrect and/or faulty (star-delta)
connections in the terminal board of the motor Tighten or replace the clamps and terminals
Motor (coil) faulty Check and repair or replace the motor
Pump unit mechanically seized Check and repair the pump unit
Power supply cable is damaged Replace the power supply cable
Check valve faulty Replace the check valve
Foot check valve faulty Replace the foot check valve
7.5 The thermal overload protection triggers
The motor thermal overload protection triggers occasionally, or after the unit has been running
for a few minutes.
Cause Remedy
It is calibrated at a value too low in relation to
the rated current of the motor Recalibrate
Input voltage outside the rated limits Make sure the voltage values are correct
Unbalanced input voltage Make sure the voltage of the three phases is
balanced
Incorrect working curve (flow rate greater than
the maximum permitted flow rate) Reduce the required flow rate
Liquid too dense, presence of solid or fibrous
substances (unit overloaded)

Reduce the density of the liquid and/or

Remove the solid substances and/or

Increase the size of the motor
Room temperature too high, exposure to
sunlight

Lower the temperature at the point of the
thermal overload protection and/or

Protect against direct sunlight
Unit faulty Send the unit to an authorised workshop for
testing
7.6 The unit runs but there is little or no flow rate
Cause Remedy
Motor turns in the wrong direction Check the direction of rotation and change it if
necessary
Incorrect priming (there are air bubbles in the
suction pipe or in the unit) Repeat the priming procedure
Cavitation Increase the NPSH
4
available in the system
Check valve locked in closed or partially closed
position Replace the check valve
Foot check valve locked in closed or partially
closed position Replace the foot check valve
Discharge pipe throttled Remove the throttling
4
Net Positive Suction Head