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

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5. Pressure System Installation and Pump Controls
Davey submersible borehole pumps may be used as a pressure system in conjunction with pressure tanks
providing a suitable draw off capacity. When selecting a pressure tank, make sure that the rated tank pressure is at
least 10% greater than the pump pressure at the bore head. Also make sure that the tank draw off capacity is large
enough to limit the pump’s starts to an absolute maximum of those relevant to the motor used.
While small capacity tanks may be used, extreme care must be taken to ensure the pump unit does not ‘cycle’. It may
be necessary to fit more than one pressure tank to provide the required draw off or to help prevent pump cycling.
The installation of a ‘drilled check valve’ to the pressure tank may assist in the prevention of pump ‘cycling’
problems. For further information on these contact your Davey Dealer.
NOTE: Any automatic switching of the pump giving excessive starts per hour will shorten the life of the pump
and damage caused may effect warranty cover.
Typical Submersible Installation
A. PUMP CONNECTED FOR MANUAL OPERATION.
B. PUMP INSTALLED AS AN AUTOMATIC PRESSURE SYSTEM INCORPORATING PRESSURE TANK AND
PRESSURE SWITCH.
WARNING: Failure to use correct starting equipment and overloads may damage your submersible mo-
tor. This damage may not be covered by warranty.
PRESSURE SWITCH WIRING: Starting current (inrush current) from large motors may damage pressure
switch. Pressure switches installed with motors of 1-1/2hp (1.1kW) or larger should be wired through a
magnetic contactor to aviod burning out pressure switch. Consult your Davey Dealer for further information.