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Submersible pumps are installed in bores and are hardly accessible for visual inspection. However one can diagnose troubles by tuning one’s ear to the acoustical sound produced by discharge line. This can however be done by the user rather than a trained mechanic as frequency of sound is typical to a typical installation. It is advisable to touch one’s ear to delivery line and observe the sound emitted by the pump. In a daily routine inspection following points should be noted:

Sound emitted by the pump.

Voltage supplied to the pump.

Current drawn by the pump.

Visual discharge at the outlet of the pump.

The pump should not be operated for more than 2 Hrs. Panel must show voltage in the range 180 V-240 V for single phase and 350 V-440V for three phase. Any voltage outside this range is likely to harm the motor. Current drawn at different available voltages for a particular installation should be recorded and checked on a daily basis. Any abnormal current drawn by the pump set can be a possible cause of trouble. Visual discharges at outlet of the pump will depend on various factors like voltage availability on the site, the depth of water available, and periodic yield of the borewell.

Installation and Maintenance

Periodic Checks

It is better to carry out periodic checks to determine the health of Submersible Pump and possible troubles. This can be done in the following ways.

Install a Pressure guage (make provision while installation). Completely close the outlet of the pump by using a throttle valve. Record the pressure guage reading periodically. Any drop in pressure more than 15% of original value can suggest a problem in the pump. (Ref. Trouble shooting chart)

Periodic inspection should be carried out to determine the insulation resistance of winding.


Ensure that the pump portion is kept resting on the N.R.V. and not on the coupling

Ensure that for prolonged storage, the motor is filled with cold drinking water (NOT DISTILLED WATER)

Run the pump for at least 1/2 an hour every week if the pump remains under shut down for a longer period, to resume instant service at any time

Do suspend the pump set 3-4 mtr. above the bottom in borewells.

Ensure that the pump is installed at least 1 mtr. below the lowest level of water.

Ensure proper coupling by lifting the shaft assembly with screw driver which should lift by 0.5 to 1.0 mm approximately

Run the motor for minimum 30 mins after commissioning until clear water starts flowing.

It is necessary to operate a submersible pump set against a throttle discharge valve. The minimum rate of flow should be at least 25% of the rate of flow at an optimum efficiency point on the chart to avoid overheating of the pump set

Use Overload Protection Relay

Ensure fitment of water level guard for low yield borewells.

Use the 500 volt D.C meggar only.


Don’t switch on/off for more than 15 times in an hour with minimum ol 1 min. interval between two successive start and stops to avoid damage to the motor.

Don’t use the pump if the water is sandy or acidic.

Don’t run the pump if any defect is observed.

Don’t run the pumpset in dry condition

Don’t run the pumpset against the closed discharge valve for more than 5 minutes to avoid over heating of the motor.

Don’t use new pumpset for developing or surging well or to free it from sand when the bore is a new one.

Don’t switch on the pumpset under any circumstances before filling the motor with drinking water.

Don’t start the pump without fitting sluice valve and water level guard.

Don’t operate the three phase pump in case of single phasing.

Don’t Lift the Motor with the help of its Cable.

Don’t bend the cable sharply

Don’t use extra washer in motor and pump coupling for extra play.