Product Manual
7
Troubleshooting
Operation
To turn the unit on, simply move the power switch to the ON position. The alarm buzzer will
sound and the Low Output LED will come on briey, and then the green OUTPUT ON LED will
illuminate.
The unit’s output voltage is preset at the factory. You may check this voltage at the output
terminals of the unit with a good digital voltmeter. If you wish to adjust the output voltage,
use a very small at blade screwdriver to rotate the potentiometer. Clockwise increases the
output voltage, and counter clockwise decreases it.
If the red OVERTEMP 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 red LOW INPUT LED and the audible alarm comes on, the input voltage has dropped
to below a usable level.
If the red LOW OUTPUT LED and the audible alarm comes on, and the green OUTPUT ON
LED is still on, but it is dimmer than normal, the unit is overloaded. Refer to the manufactur-
ers specications and add up the current ratings for each device connected to the unit. Make
sure that the total load does not exceed the continuous rating of the unit. Remove loads as
necessary to prevent the LOW OUTPUT LED from coming on.
If the LOW OUTPUT LED and the audible alarm come on, and the green OUTPUT ON LED
is completely off, the output of the unit has been shorted out, or there has been an internal
failure. Turn the unit off, disconnect all the loads connected to it, and turn it back on again. If
it comes on normally, turn it off again, reconnect one load, and turn it back on. Continue recon-
necting loads until the short circuit condition returns. Turn the unit off, disconnect the faulty
load, and reconnect it only after the fault is found and rectied. If the condition still exists
even after all the loads have been disconnected, the unit is defective, and must be returned to
the factory or an authorized service centre for repair.
If the unit will not turn on at all, check the input fuse. To do this, rst turn off the unit and
disconnect the I/P power. Remove the fuse and check it with an ohmmeter. If it is blown,
replace it with a new one. If that fuse blows as well or the unit still will not turn on, it is
defective, and must be returned to the factory or an authorized service centre for repair.