30
Power voltage/Earthing
Points to be checked
• Check that power voltage is turned off.
Insert the plug all the way seated in a socket.
NOTE
• Do not share a power source with a high power device which may generate a surge voltage. Otherwise an
electronic circuit may fail. The conductive noise caused by an inverter also affects the circuit.
• Energize the pump with a power voltage via a mechanical relay or switch. Do not fluctuate the voltage, or
CPU may malfunction. See page 31 for the precautions for ON-OFF control by a mechanical relay.
Apply power sharply
Do not apply gradually
Surge voltage
The electronic circuit in the control unit may fail due to a surge voltage. Do not place the
pump close to a high power device of 200V or more which may generate a large surge
voltage. Otherwise, take any of the following measures.
• Install a surge absorption element (such as a varistor with capacity of 2000A or more)
via power cable or,
Recommended varisters:
Panasonic ERZV14D431
KOA
NVD14UCD430
See manufacturer's catalogues for detail.
•
A noise cut transformer via the power cable.
Surge absorption element
Noise cut transformer
POWER
ON
OFF
TIME
POWER
ON
OFF
TIME
1
Wiring
