Specialty Concepts SCS/90 - Manual (Page 21)

F I E L D T E S T P R O C E D U R E : S C S
Test equipment required: digital multimeter, jumper wires
Conditions: Sunny or bright overcast if possible
Precautions: This procedure assumes that the system panels are installed and operational, or
at least capable of producing at least 15 volts for a 12 volt system (proportionately higher for
higher nominal system voltages). When connecting and disconnecting the batteries and array
as instructed in this procedure, be sure that the circuit breakers are in the “OFF” or down
position, otherwise arcing will occur. On bright days, it may be advisable to partially cover the
array to reduce current produced.
WARNING: Most batteries produce hydrogen gas when charging, which is extremely
explosive. Avoid making sparks in the vicinity of batteries, and provide adequate battery
ventilation.
1) Inspect temperature compensation sensor and cable for damage. If damaged, the
controller will no longer operate. See TEMPERATURE COMPENSATION section.
2) Remove the VOLTAGE SENSE (+) jumper (or disconnect VOLTAGE SENSE (+) wire if
remote sensing is used).
3) Switch Battery, Array and Load circuit breakers off. Disconnect the BATTERY (+) wire, the
LOAD (+) wire and the SOLAR ARRAY (+) wires from the controller. Secure each wire
away from any possible contact with other wires, metal chassis, enclosures etc. Switch
Battery and Array circuit breakers back on.
4) Measure the resistance between the SOLAR ARRAY (+) and BATTERY (+) terminals on
the controller. It should read open (more than 10M
Ω
).
5) Switch Array circuit breaker off. Reconnect the solar array to the controller. Switch Array
circuit breaker on.
6) Measure the voltage between the SOLAR ARRAY (+) and SOLAR ARRAY (-) terminals to
ensure it is at least 15 volts (30 for 24 volt units, 45 for 36 volt units, 60 for 48 volt units)
7) If the controller is in charge mode, go to step 8. If it is not, briefly connect a jumper wire
between the SOLAR ARRAY (+) and BATTERY (+) terminals on the controller. When the
controller switches to charge mode, remove the jumper.
8) The controller should now be in charge mode. Measure the voltage between the BATTERY
(+) and BATTERY (-) terminals on the controller. It should be about the same as the panel
voltage from step 6.
9) Install a jumper between SOLAR ARRAY (+) and VOLTAGE SENSE (+). The controller
should switch out of charge mode. Remove the jumper.
10) Switch the Battery and Load circuit breakers on. Measure the resistance between the
LOAD (+) and BATTERY (+) terminals on the controller. It should read closed. Switch
Battery and Load circuit breakers off.
11) Connect BATTERY (+) wire. The LOAD DISCONNECTED light should go on, and battery
voltage should be measured at the load terminals. Switch the Battery and Load circuit
breakers off.
12) If the controller fails any of these tests, it is defective. If all tests are passed the problem is
most likely elsewhere in the system.
5 / 1996