User Manual
gpelectric.com | [page 15]
®
The GP-PWM-10-FM and GP-PWM-30-SB oer a standard USB connector for delivering 5.0 VDC to small mobile appliances such as cell
phones, tablets or small music players. This charging port is capable of supplying up to 1500 mA of current.
Remove the rubber cover of the USB terminal to access the terminal.
The USB charging port is always active when the USB symbol appears on the display.
The controller disables the USB charger automatically if the battery voltage drops below 11.0 VDC. If there is enough current from the PV
panel/array available to charge the Battery to above 12.8 VDC, the USB terminal will be enabled again.
WARNING: Do not connect the charging device anywhere else! USB-Negative contact is connected to battery negative.
Before a problem is suspected with the system, read this section. There are numerous events that may appear as problems but are in fact
perfectly normal. Please visit gpelectric.com/support for the most up-to-date
FAQs.
Q. It seems like my ooded batteries are losing water over time.
A. Flooded batteries may need to have distilled water added periodically to replace uid loss during charging. Excessive water loss during
a short period of time indicates the possibility of overcharging or aging batteries.
Q. When charging, my ooded batteries are emitting gas.
A. During charging, hydrogen gas is generated within the battery. The gas bubbles stir the battery acid, allowing it to receive a fuller state
of charge. Important: Ensure batteries are in a well-ventilated space.
Q. My voltmeter shows a dierent reading than the GP-PWM-10-FM display.
A. The meter value on the GP-PWM-10-FM display is an approximate reading intended for indication purposes only. There is an approximate
0.1 volt inherent error present that may be accentuated when compared with readings from another voltmeter.
There may be a slight dierence between the battery voltage displayed on the GP-PWM-10-FM display and the battery voltage measured
at the battery terminals. When troubleshooting using a voltmeter, check both the battery voltage at the GP-PWM-10-FM controller terminals
and battery voltage at the battery terminals. If a dierence of more than 0.5 volts is noted, this indicates a large voltage drop possibly
caused by loose connections, long wire runs, small wire gauge, faulty wiring, a faulty voltmeter, or all the above.
5.5 USB CHARGING
5.6 FREQUENTLY ASKED QUESTIONS
GP-PWM-10-FM/GP-PWM-30-SB SOLAR CONTROLLER