Instruction manual V 2.3
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PWM 230 - PWM 400 - PWM 400/7.5
Instruction manual
pressure loss that the system cannot compensate. The result is that pressure is constant on the
PWM device but not on the user.
“bP” Blockage due to a fault of pressure sensor
If the PWM does not detect the presence of a pressure sensor the pump blocks and the “bP” error is
signalled. This error condition begins as soon as the problem is detected and ends automatically 10 sec after
the correct conditions are restored.
"LP" Blockage due to low supply voltage
This error condition occurs when the line voltage at the supply terminals falls below 180V and is reset only
automatically when the voltage at the terminal rises above 200V.
If the wiring section is insufficient, this block may occur when the electro pump is started even if a higher
voltage is measured when the PWM is in stand-by mode.
"SC" Blockage due to direct short circuit between the phases of the output terminal
PWM is equipped with protection against short circuit that may occur between the phases U, V, W of the
"PUMP" output terminal. When this block status is indicated, you should remove the short circuit and
carefully check the wiring integrity and the installation in general. Once these checks have been made you
can try to recover from the error by simultaneously pressing the “+” and “–“ keys;
anyway, this will have no
effect until 10 seconds have elapsed from the moment in which the short circuit occurred.
Whenever a short circuit occurs, an event counter is increased and saved in the permanent memory
(EEPROM).
AFTER THE HUNDREDTH SHORT CIRCUIT THE MACHINE BLOCKS PERMANENTLY
AND IT WILL NO LONGER BE POSSIBLE TO UNBLOCK IT!
6.1 Manual reset of error condition
In error status the operator can recover from the error by forcing a new attempt, which is obtained by
simultaneous pressure of the “+” and “–“ keys.
6.2 Automatic reset from error conditions
The system automatically attempts to recover from the following error conditions:
-
"bL"
Blockage due to lack of water
-
"LP"
Blockage due to low supply voltage
-
"HP"
Blockage due to high supply voltage (or high internal voltage due to a sudden motor braking)
-
"ot"
Blockage due to overheating of the power output stages
-
"oC"
Blockage due to overcurrent in the pump
-
"oF"
Blockage due to overcurrent in the output stages
For example, if the electro pump blocks due to lack of water, the PWM will automatically start a series of
tests in order to ensure that the machine really has no water and that this condition is permanent. If a
recovery attempt succeeds (e.g. if water has come back), the tests will stop and the PWM will return to
normal operation.
