Sun Pumps SJT10-120BL User Manual
Page 16
9. Check for proper controller input voltage. If the pump is not running, the input voltage should be the array open circuit voltage,
(Voc). Verify that this voltage is below the maximum input voltage allowed for your controller (model dependent see Table 1).
Check the Voc on the label on the back of the solar modules and multiply this figure times the number of modules that are
connected in series. This number should be + - 10% of the measured reading. If it is not then confirm all electrical terminations are
tight and secure. Use a DC volt meter to check each solar module for proper open circuit voltage (Voc). One bad module will drop
the voltage on the complete series string.
PUMP IS RUNNING BUT THE OUTPUT IS LOW
1. Make sure you have full sun light at midday, that there are no clouds and no shadows on any part of the array. Then verify power
going into the controller by measuring the voltage and current. Check this against the pump chart for your specific application.
2. If the power is correct for your pump model and array size then make sure the pump wires are connected to the proper terminals. If
two wires are reversed the motor will be running in reverse. It may still pump but not at the full rated output.
3.
If the wires are correct verify that your system does not have any leaks where water can be lost. If you cannot determine the
problem, contact Sun Pumps for further assistance.
4.
Make sure the water in the well is not drawing down past the suction capability lift of the pump
.
5.
Check the suction screen on the foot valve to see if it is plugged.
6. Make sure the hole in jet nozzle is not plugged. (Part No. 41459)
PUMP DRAWS EXCESSIVE CURRENT
(More than the rating of the pump, but less than the rating of the controller)
1. Check wiring diagram for proper connection.
2. Check for skinned wires or faulty underwater splice.
3. Check for locked motor armature. With the pump out of the well, remove the pump end from the motor (if this is not feasible skip
this step and contact Sun Pumps). Allow the controller to attempt to start the motor. If the motor still does not run, contact Sun
Pumps for further assistance.