Checking Pump Performance - Grundfos SP Instrucciones De Instalación Y Funcionamiento

9.1.1 Ohm value chart
Motor not yet
installed
Motor in well (ohm
readings are for
submersible drop
cable plus motor)

9.2 Checking pump performance

The troubleshooting chart on page
require that you test the pump's performance
against its curve. To do so, perform these steps:
1. Install pressure gauge.
2. Start pump.
3. Gradually close the discharge valve.
4. Read pressure at shut-off.
5. After taking reading, open valve to its
previous position.
6. To calculate pump performance, first convert
psi reading to feet.
(For water: psi x 2.31 = ____ feet).
7. Add this to the total vertical distance from the
pressure gauge to the water level in the well
while the pump is running.
8. Refer to the specific pump curve for the shut-
off head (pressure) for that pump model.
If the measured head is close to the curve,
pump is probably OK.
Ohm value chart
Ohm value
2,000,000 (or more)
1,000,000 (or more)
500,000 - 1,000,000
20,000 - 500,000
10,000 - 20,000
Less than 10,000
20 may
Megaohm Condition of motor and leads/
value recommended procedure
2.0 New motor.
Used motor which can be reinstalled
1.0
in the well.
A motor in reasonably good
0.5 - 1.0
condition.
A motor which may have been
damaged by lightning or with
0.02 - 0.5
damaged leads. Do not pull the
pump from the well for this reason.
A motor which definitely has been
damaged or with damaged cable.
The pump should be pulled from the
0.01 - 0.02
well and repairs made to the cable
or the motor replaced. The motor
will still operate, but probably not for
long.
A motor which has failed or with
completely destroyed cable
insulation.
0 - 0.01
The pump must be pulled from the
well and the cable repaired or the
motor replaced. The motor will not
run in this condition.
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