User Manual

Installation
28 975-0004-01-02 Rev D
Using a Digital Voltmeter to Adjust Voltage Settings
A digital DC voltmeter (DVM) can be used to provide a more
accurate setting of voltage parameters. Test points are
provided at the mid-range on the scales for this purpose.
The potentiometers are equipped with removable knobs to
prevent accidental mis-adjustments. If the knobs are missing,
a 5/64" hex-head driver can be used to adjust the settings.
To test and adjust the voltage setting using a DVM:
1. Point the potentiometers to the mid-range position.
2. Connect a digital voltmeter from one of the common
negative terminals on the circuit board and the small test
point located to the left of each potentiometer at the
nine o’clock position. See Figure 2-15.
The test point provides a reading from 0 to 2 volts.
(Multiply this value by “2” for 24-volt system and by
“4” for 48-volt system.)
3. Add the value obtained in step 2 above to the lower value
of the adjustment range/voltage scale being used.
For example for a 12-volt system:
To set the BULK voltage to 14.4 volts:
1. Point the BULK potentiometer to the mid-range position.
2. Adjust the potentiometer until the DVM displays
1.4 volts (13.0 V + 1.4 V = 14.4 V).
For example for a 24-volt system:
To set BULK voltage to 28.2 volts:
1. Point the BULK potentiometer to the mid-range position.
2. Adjust the potentiometer until the DVM displays
1.1 volts (1.1 x 2 [24 volt] = 2.2 + 26.0 = 28.2).