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Regular Check-Ups
At regular intervals, depending on the conditions and time of operation, the following checks
should be made:
1.
Pump meets required performance and is operating smoothly and quietly;
2.
There are no leaks, particularly at the shaft seal;
3.
The motor is not overheating;
Remove and clean all strainers or filters in the system;
4.
Verify the tripping of the motor overload protection;
5.
6.
Check the operation of all controls. Check until control cycling twice and adjust if necessary;
7.
If the pump is not operated for unusually long periods, the unit should be maintained in ac-
cordance with these instructions. In addition, if the pump is not drained, the pump should be
manually rotated or run for short periods of time at monthly intervals.
If the pump fails to operate or there is a loss of performance, refer to the Troubleshooting
Section.
WHEN WORKING WITH ELECTRICAL CIRCUITS, USE CAUTION TO AVOID
ELECTRICAL SHOCK. IT IS RECOMMENDED THAT RUBBER GLOVES AND BOOTS
BE WORN, AND METAL TERMINAL BOXES AND MOTORS ARE GROUNDED
BEFORE ANY WORK IS DONE.FOR YOUR PROTECTION, ALWAYS DISCONNECT
THE PUMP FROM ITS POWER SOURCE BEFORE HANDLING.
Preliminary Tests
Supply
Voltage
Current
Measure
How to Measure
By means of a volt meter, which
has been set to the proper scale,
measure the voltage at the pump
terminal box or starter.
On three-phase units, measure
between the legs (phases).
How to Measure
By use of an ammeter, set on the
proper scale, measure the current
on each power lead at the terminal
box or starter. See motor name-
plate for amp draw information.
Current should be measured when
the pump operating at constant
discharge when the motor is fully
loaded.
Operating Parameters
Troubleshooting
What it Means
When the motor is under load, the voltage
should be within ±10% of the nameplate
voltage. Larger voltage variation may
cause winding damage.
Large variations in the voltage indicate
a poor electrical supply and the pump
should not be operated until these varia-
tions have been corrected.
If the voltage constantly remains high or
low, the motor should be changed to cor-
rect the power supply.
What it Means
If the amp draw exceeds the listed service
factor amps (SFA) or if the current unbal-
ance is greater than 5% between each leg
of three-phase units, check the following:
1. Burned contacts on motor starter;
2. Loose terminals in starter or terminal box or
possible wire defect. Check winding and in
sulation resistances;
3. Too high or low supply voltage;
4. Motor windings are shorted;
5. Pump is damaged causing a motor overload.
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