Specialty Concepts SCS/90 - Manual (Page 16)

T R O U B L E S H O O T I N G : S C S
PROBLEM DESCRIPTIONS
BATTERY UNDER CHARGED
CONTROLLER NOT CHARGING AT ALL, ALWAYS IN THE FLOAT MODE ("CHARGING"
LIGHT OFF)
Check to see that the circuit breakers are all on, and that the controller is receiving voltage (at
least about nominal system voltage) from the battery and the solar panels. If it is,
momentarily disconnect and reconnect the panels, using the array circuit breaker. The
controller should reset into the full charge mode ("CHARGING" light on). If it does not
reset, the controller may be defective.
See number 8 above. A damaged sensor or wire will cause the controller to malfunction.
CONTROLLER STOPS CHARGING TOO SOON, AT TOO LOW A VOLTAGE
See number 6 above: Try to monitor the voltage at the "VOLTAGE SENSE" terminals when the
controller actually switches. Most often, when a controller is operational, it is switching the
correct voltage. If the battery is not reaching the charge termination set-point voltage
before the controller switches, it is usually an error in the voltage that the controller is
sensing, not a controller failure.
See numbers 11 and 13 above: A poor connection between the battery and the controller
results in a voltage drop during charging periods (larger drop for higher current) that
disappears when charging stops. This voltage drop results in a higher voltage being
sensed at the controller than is actually at the battery.
CONTROLLER CLICKS AND CHATTERS, PARTICULARLY IN THE MORNING AND EVENING
See numbers 11 and 13 above: Check the connection to the battery. A poor connection at the
battery will cause the relay to chatter under low light conditions and the controller to remain
in float mode during full sun.
CONTROLLER NOT CHARGING, "CHARGING" LIGHT DIM, BATTERY VOLTAGE VERY LOW
See LVD trouble shooting section. If the LVD circuit is not operating, the battery can be
discharged to a very low voltage. If the battery is extremely low, there might not be enough
voltage to operate the controller. The charging relay requires a minimum operating voltage
to engage and allow charging. If the battery is down to 9 volts or lower on a 12 volt system,
(17 on a 24 volt) connect the battery directly to the array (or use an auxiliary charging
source) until sufficient charging has occurred to increase the voltage. Note: Battery life
depends on the number, time and the depth of the discharges. Severe battery damage can
result when batteries are deeply discharged and not recharged immediately.
"CHARGING" LIGHT ON AT NIGHT
Review the "REVERSE CURRENT PROTECTION" and "CONNECTION SEQUENCE" sections
of this manual. The reverse leakage timer may cause the "Charging" light to be on for a few
hours each evening. Also, the light will stay on during the night of the first day of
installation or if the array has been manually disconnected that day. If the light stays on all
night every night, the timer may be defective.