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9. Trouble-shooting chart
LCD does not switch on after powering
the unit
Check the connecting flat cable between the LCD board (attached to
the cover) and the control board
Check the fuses
Check that the power cables are properly connected.
Power line is interrupted by the
differential protection contactor
Check the leakage current to ground of EMC filter
Following a rapid off/on the power supply, the differential contactor
can interrupt the power. After turning off the inverter it is
recommended to wait at least 1 minute before restarting.
When performing sensor test
operation, SENSOR OFF alarm occurs
Check that the sensor cable is properly connected to the sensor device
and to the device.
Make sure that the sensor and its cable are not damaged.
Check that the operating range of sensor is of 4 -20 mA type and the
value of 15 V is within the voltage feed range of the sensor.
Frequency and pressure oscillation on
constant pressure control mode
Check if the water tank and its air pressure are correctly set. It may be
necessary to increase the tank volume or reduce the pre-charge
pressure.
Check the ki & kp parameters (Control parameters menu). At first, it is
suggestable to increase the Ki value. If it not enough reduce of one unit
the Kp value.
DOL pump stops and starts
continuously
Increase delta control.
Check to see if the water tank and it’s air pressure are correctly set. It
may be necessary to increase the tank volume or reduce the pre-
charge pressure.
Measured pressure drops too much
before inverter starts the pump.
Decrease the delta start value (Control Parameters menu) .
Check to see if the water tank and it’s air pressure are correctly set. It
may be necessary to increase the tank volume or reduce the pre-
charge pressure.
Modify the value of ki & kp parameters (Control Parameters menu).
At first, it is suggestable to reduce the Ki value. If it is not enough
increase of one unit the Kp value.
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