How to troubleshoot the GP-PWM-10-FM Solar Controller
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Common solar controller trouble shooting
The solar controller requires power from the battery in order for it to operate (9-14.9 volts) . The first step in troubleshooting any solar controller is to determine if you have 12 volts to the controller. This is done by measuring the input from the battery on the back of the controller. If the battery voltage is below 9 volts it will not power the controller. Check the inline fuse between the battery and the controller and your battery and terminal block connections on the controller.
If the controller is in an error state first try a soft reset. (Only on 4 button units) This is done by holding down all 4 buttons on the front of the controller for 15 seconds. If this does not work a hard reset is required. This can be done in a couple of different ways . You want to eliminate all power going to the controller for at least a half hour. You can remove the controller from the wall and remove one wire from solar one wire from batteries for the half hour interval. You can pull the fuse between the controller and the battery and cover the panels to stop any light from getting through for the same interval. See if this clears the error state.
Trouble shooting GP-PWM-10-30-SQ Models.
Error Codes
PO1:
Indicates a polarity reverse error from the solar panel. In this case, the negative wire has been applied to the positive post of the controller and the positive applied to the negative post.
PO2:
Indicates the solar voltage coming into the controller exceeds 26.5 volts; this would be the max voltage the controller can handle. If this error occurs check the output of the solar panel with a multimeter to determine if it is sized correctly for the controller. Make sure the panels are not wired in series to the controller as a series install would double the voltage input to the controller
601:
Error indicates a low voltage at the solar controller. The solar controller requires power from the battery in order for it to operate (6-14.9 volts). The first step in troubleshooting any solar controller is to determine if you have 12 volts to the controller. This is done by measuring the input from the battery on the back of the controller.
If the battery voltage is below 6 volts, it will not power the controller. Check the inline fuse between the battery and the controller and your battery and terminal block connections on the controller. If the voltage is below 6 volts, the controller will not power up. Check input voltage with a multimeter on the back of the controller. Then move your way back towards the battery.
Check the inline fuse on the positive line. If blown it will affect the output. It also may simply be a low battery that may require another source to charge it up again.
602:
Error indicates a polarity reverse error from the battery. In this case, the negative wire has been applied to the positive post of the controller and the positive applied to the negative post.
603:
Error indicates an overcharge issue at the battery. First measure the battery voltage with a multimeter and determine if they are truly that high. If they are then a charging source is putting too much current into the battery. You will have to determine which source is doing this the:
- Solar controller?
- Alternator?
- Converter/charger?
We have also seen issues where the solar wires have been placed in the battery connections on the solar controller. The solar panels can produce 16-23 VDC and if these wires have been placed on the battery connection on the solar, it will indicate this error. Check on the back of the controller with a multimeter to confirm.
Then swap the wires to the correct position if this is the case. (there is a label on the back of the controller to indicate the correct positions).
Note the 604 error is redundant as we do not include temperature sensors with this controller.
Low Current error 12U
A 12u error will appear on the screen when the unit boots initially off the battery it will also appear if the controller is getting volatge but not current from the solar panel. This can occur early in the morning when there is sun on the panels but the sun is not intense enough yet for the panel to produce any current. It would go away as the sun got higher in the horizon. It will more consistently come on if the solar panel is getting voltage but not current. This would indicate an issue with the solar panel.