Product Manual
8
Troubleshooting
If the red Over-temperature LED and the audible alarm come on, the unit has overheated, and
it will shut down until it cools off sufciently. You may not have allowed sufcient space
around the unit for cooling, or there may be too many devices connected to the output of the
unit. Either reduce the number of devices connected to the unit, or reposition the unit for
better cooling. If necessary, direct a stream of moving air over the unit.
If the yellow Low Input LED comes on, the input voltage has dropped below 19 VDC (27 VDC
on the -24 version). To keep from completely discharging the batteries (if the battery charger
is being operated from batteries), the unit will shut down until the voltage recovers to 21 VDC
(29 VDC on the -24 version). Make sure that the charging system is operating properly, and
that the wires connecting the input voltage to the unit are not corroded or damaged.
Operation
To turn the unit on, simply move the power switch to the ON position. The alarm buzzer will
sound and the Low Input LED will come on briey, and then the green Output ON LED will
illuminate. If you wish to adjust the output voltage, remove the cover plate (secured by 2
screws) to expose the output adjust potentiometer. Reach in with a very small at blade
screwdriver to rotate the potentiometer. Clockwise increases the output voltage, and counter
clockwise decreases it. When you are done, replace the cover plate and securely tighten the
screws.
Connect only one bank of batteries to the unit. Connect the ‘+’ outputs of the unit to the
positive lead of the battery bank. Connect the ‘-’ outputs of the unit to the negative lead of
the battery bank. The ‘+’ outputs are electrically common and have output isolation diodes
to prevent damage to the unit if the battery bank is accidentally connected backwards.
The ‘-’ outputs are electrically common. If you accidentally connect a battery in reverse,
the output fuse (AGC 30) will blow. If this happens, correct the connection of the battery,
conrm it with a voltmeter, and then replace the fuse.
When the unit is rst turned on, it will charge the batteries at a constant current of 50 amps
for a –12 model and 38 amps for a –24 model. During this time, the red ‘Charging’ LED will
be on. If the batteries are seriously discharged, the ‘Low Output’ LED and the audible alarm
will also come on. After a period of time, which may be minutes to hours, the batteries will
reach the oat voltage, and the charging current will reduce as necessary to maintain the
batteries at that voltage. Once this happens, the red ‘Charging’ LED will go off. You may
now check the oat voltage at the output terminals of the unit with a good digital voltmeter.
As shipped from the factory, the unit is preset to 13.6 volts, which is generally recommended
for lead-acid batteries. The generally recommended voltage for gel type batteries is 13.9
volts. Your battery supplier may also recommend a different voltage. If you need to adjust
the oat voltage, refer to the section above for the correct procedure.