KSB PumpDrive 2 - Page 192

11 Trouble-shooting
192 of 212
PumpDrive 2
Alert Possible causes Remedy
14)15)
Thermal motor
protection
PumpDrive power < motor power or
Output current < motor current
Wrong device ordered; mount larger PumpDrive
model.
Carrier frequency of frequency inverter set
too high
Set carrier frequency to permissible range.
Fluctuating DC link voltage when pump is
not running
Check mains voltage quality.
Fluctuating DC link voltage when pump
operates at nominal values
Check mains voltage quality.
Incorrect motor current measurement Measure current using suitable snap-on ammeter
and compare with the information displayed on
the control panel.
NOTE!Approx. 10% tolerance is permissible.
Pump runs in reverse when motor is not
supplied with current
Check swing check valve.
Motor voltage output is too low at nominal
load, < 380V at nominal load
Check line input voltage; enter motor current at
380V mains voltage; fit larger-sized motor.
Heat sink
temperature high/
PCB temperature
high
Ambient temperature of frequency inverter
> 50 °C
Impermissible operating range; mind power
derating.
Dirt in external fans Clean fans.
Heat sink/cooling fins dirty Clean heat sink/cooling fins.
Carrier frequency of frequency inverter set
too high
Set carrier frequency to permissible range.
Frequency inverter power < motor power or
Output current < motor current
Wrong device ordered; mount larger PumpDrive
model.
Frequency inverter mounted incorrectly External fans must point upwards; on the wall-
mounted model, the back of the heat sink must
be closed.
Undervoltage Line input voltage too low Check the mains voltage.
Fluctuating DC link voltage when pump is
not running
Check mains voltage quality.
Mains fuse has tripped Fit new mains fuse.
Brief interruption of mains voltage Check the mains voltage.
Overvoltage Line input voltage too high Check the mains voltage.
Fluctuating DC link voltage when pump is
not running
Check mains voltage quality.
Ramp times too short Select longer ramp times.
Pump runs in reverse when motor is not
supplied with current
Check swing check valve.
Overcurrent/
dynamic overload
protection
Mains power supply connected incorrectly Connect mains power supply to L1, L2, L3, PE.
Motor terminal board wired incorrectly
(delta/star)
Wire motor terminal board correctly.
Incorrect motor data set (3-3-2) Match motor data to motor used.
Parallel operation of motors This mode of operation is not permissible.
Sensor cable shielding connected incorrectly Connect sensor cable shielding to PE on one end
only.
PumpDrive power < motor power or
Output current < motor current
Wrong device ordered; mount larger PumpDrive
model.
Ramp times too short Select longer ramp times.
Wrong direction of rotation of the pump Change the direction of rotation of the motor via
the phase sequence.
Pump blocked mechanically/runs sluggishly Check pump.
Carrier frequency of frequency inverter set
too high
Set carrier frequency to permissible range .