Davey 4 Submersible Borehole Pumps SERIES J - Manual (Page 5)

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Davey supply a range of control boxes incorporating various switching devices and the use of these products
is recommended. Alternative systems may be connected directly into the supply line to 240 volt motor control
boxes, provided the switching device used has an adequate current rating. If the current rating of the switch is
not adequate, a contactor must be wired into the supply and the switching device used to control the contactor’s
coil. In any case, where a single phase motor has a control (starter) box, no additional switching devices should be
wired between the motor and box.
In the case of three phase motors, all switching devices should be wired to the starter’s control coil, and on no
account should they be used to directly break the supply circuit to the pump.
6. Electrical Connection
All wiring should conform to the requirements of local and national electrical codes. If in doubt, contact your
electricity supply authority. Cables should be insulated and sheath type, conforming to AS3100 and rated for
continuous immersion in water.
For full motor connection details consult the relevant motor installation & operating instructions.
WARNINGS:
A.
BEFORE installing or servicing your pump check to ensure that electrical power is turned off and
disconnected.
B. Single phase motors with in-built thermal overloads may restart automatically and unexpectedly. Ensure
that warning A. above is observed at all times.
All electrical connections should be checked before the pump is installed in the bore. If possible, it is a good
practice to run the pump briefly in a container of water (water level must be well over the suction inlet screen) to
check on operation before installation in the bore. The drop cable should be secured to the drop pipe at three (3)
metre intervals using waterproof plastic tape.
7. Direction of rotation - Three phase motors only
Any three phase motor connected to a supply line for the first time may rotate in either direction. It is, therefore
necessary to find out it the motor is rotating in the correct direction. If the rotation is to be checked on the surface,
proceed as follows:
- Pour clean water into the discharge by holding the non-return valve open so that the shaft bearings and
impellers become wet.
- Turn the power on and off for a very short time and check the shaft rotation.
- The correct rotation is anti-clockwise by looking down from the discharge.
- To correct a reversed rotation, change any two leads (except earth) from the three phase supply at the motor
starter.
8. Three Phase Connection
Three phase models must be wired with a contactor with approved ‘quicktrip’ overloads set correctly.
Davey recommend the use of overloads which also have the ability to detect “single phasing” or “dropped phase”
conditions in the power supply.
WARNING: The dry rotation should not exceed a period of one to two seconds, otherwise seizing may
occur due to inadequate lubrication.
Before finalising wiring connections, check that motor rotates in direction of arrow (clockwise when
shaft is viewed from wiring connection end). To alter rotation, change any two power leads at motor
terminals.
POWER CONNECTIONS AND WIRING MUST BE CARRIED OUT BY AN AUTHORISED ELECTRICIAN.
ALL THREE PHASE MOTORS MUST BE CONNECTED WITH APPROVED QUICK TRIP OVERLOADS.