Specialty Concepts SC3/15 - Manual (Page 8)

15. RECONNECT BATTERY AND ARRAY POWER
16. OPERATION: - Operation of the charge controller is now fully automatic. If the battery
voltage is below the Full Charge Termination set-point (14.4 volts) and power is
available from the array, the SC3/15 should start up in the full-charge mode.
During operation, it is normal for the unit to feel warm.
UNITS WITH OPTION E (LVD): - Resetting the LVD circuit to activate the loads
immediately after installation. On initial installation, the SC3/15 with LVD (Option-
E) will start out with the load disconnected (relay energized mode). The battery
voltage has to rise to the reset voltage (about 13.0 volts) to connect the loads. The
loads can be immediately activated if the array is connected to the controller and is
producing at least 17 volts open circuit, and the battery voltage is above 11.5 volts.
By disconnecting and then reconnecting the battery positive, the load should go on.
17. CHECK FOR VOLTAGE DROP (OPTIONAL): - Once the system is installed and
operational, a check on the connections is recommended. A poor connection will result
in a voltage loss that will cause the batteries to be under-charged and/or result in
excessive heat generated at the location of poor connection (wire connection or terminal
block). A poor connection to the battery will also distort the battery voltage reading and
cause the charging to stop too soon. To check the connections, a voltage multi-meter is
required and the SC3/15 must be charging with maximum expected charge current.
Battery Connection: - First, note the voltage at the battery terminals. Select the
positive and negative terminals that are used for the SC3/15 connection. Then note
the voltage at the SC3/15 wires for battery(+)(red) and battery(-)(black). Ideally, the
difference in voltage should be no more than
¼ volt.
Array Connection: - Next, note the voltage at the panel. Select the positive and
negative wires that are used for the SC3/15 connection. Then note the voltage at the
SC3/15 wires for array(+)(yellow) and array (-)(black). Ideally, the difference should
also be no more than
¼ volt.
If the voltage drop is more, suspect crimp connections that have not been soldered, in-
line fuses or fuse holders, or loose terminals. If no location of voltage drop is found,
consider using larger wires (or double up the wires) for your run.