Davey 4 Submersible Borehole Pumps SERIES J - Manual (Page 6)

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When the unit is connected and operating the phase balance should be checked. This should be within the 5%
variation. “Rolling” the leads may help to improve a small unbalance, but major phase unbalance will usually be
attributable to an input power unbalance. This must be addressed before the pump is used.
9. Earthing single and three phase pumps
Furthermore, control boxes and starters must also be earthed. If testing is used outside a well, the motor must be
connected to the power supply earth lead to prevent a lethal shock hazard.
10. Initial start-up
Before connecting the pump outlet pipe from the bore, a bend and gate valve should be screwed into the top of the
bore cap.
Never start the pump at full flow for the first time.
We recommend that the gate valve be only slightly open to start the pump.
Never open the gate valve abruptly, as this may raise sand or silt deposits.
For the first ten to twenty minutes of operation, it is suggested to keep the gate valve only slightly open, to maintain
a low flow. This low flow will prevent, in the case of excessive sand in the water, the pump seizing.
Immediately the pump has been started, catch some of the discharge water in a large container and allow solids to
settle out. If little or no sand appears, open the valve one third and pump until the discharge water is clear.
In the event of excessive amounts of sand being pumped the pump should be shut down and the bore
should be attended to before restarting the pump.
Davey submersibles are not guaranteed against failure due to pumping sand. Pumping of sand, even small
quantities of very fine sand will shorten the effective life of any pump.
The pump should be run for a period of at least 30 minutes and then the water level in the bore checked to ensure
that the water level in the bore has not dropped to a dangerously low level. Continuous monitoring of bore water
level is recommended.
Continuing operation at low water level will cause damage to the pump and motor mechanical parts due to
alternating shock pressures on the pump.
If in doubt about the draw down level of the bore, install low level probe controls, available from Davey.
11. Minimum Flow Conditions 12. Maximum Flow Conditions
Premature pump failure may result if pumps are run Premature pump failure may result if pumps are
continuously at flow rates LESS than the following: run for more than a short period at flow rates
GREATER than the following:
Flow Rates Flow Rates
Model I/Min. (GPH) Model I/Min. (GPH)
J25 Series 15 198 J25 Series 31 409
J40 Series 30 396 J40 Series 45 594
J60 Series 44 581 J60 Series 70 924
J80 Series 50 660 J80 Series 100 1320
J110 Series 80 1056 J110 Series 140 1848
J160 Series 100 1320 J160 Series 210 2772
J250 Series 150 1980 J250 Series 310 4092
All pump motors are equipped with an earth lead which must be connected to the earth of the
incoming power supply.
Do not use metal drop pipe as the earth return under any circumstances.
Never run this pump without discharge flow for more than a few seconds, as the water will heat and
cause damage to the pump or pipe lines not covered by guarantee.