Global Specialties 1332A User Manual

Page 10

CASE DISASSEMBLY AND ASSEMBLY

WARNING

Potentially lethal AC power is present whenever theline
cord is plugged into the AC outlet,even when the power
switch is OFF. Always disconnect the power cord when
opening the case. Avoid touching the fuse post on
the inside of the unit.

Should access to the inside of the unit be required,
proceed as follows

1. Remove the line cord from the AC outlet before
disassembly

2. To disassemble the case,remove the screws that
secure the cover to the chassis and lift the cover off.

3. To reassemble the case, place the cover on the

chassis, line up the screw holes, and replace the

screws.

MAINTENANCE AND RECALIBRATION

ADJUSTMENTS :
All circuitry is factory -calibrated. No user adjustments are

required.

FUSE REPLACEMENT :
Remove the line cord from the AC outlet before changing
fuses. Using the screwdriver, remove the fuse holder
cap. Replace the fuse with another of identical type and
current rating. Replace the fuse holder cap.

If a load change causes the current limit to be exceeded,
the power supply will automatically cross over to constant
current output at current limit and output voltage will drop
proportionately. In setting the current limit, allowance must
be made for high peak currents which can cause unwanted
crossover.

CONSTANT CURRENT MODE :
To select a constant current output, proceed as follows :

a. Short circuit the output terminals of the power supply.

b. Connect a DC Ammeter OR a shunt-digital voltmeter

(DVM) combination across the output terminals,
ing appropriately-guaged wire and hardware. The
recommended current ratings for the ammeter or

the shunt and the wire must be at least 10% more
than the output current of the power supply model.
The ammeter or shunt-DVM combination must be
rated better than 0.5% accuracy.

c. Turn the VOLTAGE controls clockwise. And Turn the

CURRENT controls slowly clockwise. The CURRENT
control range will be from minimum to maximum
rated output current. Adjust CURRENT controls for
desired output current.

d. Compare the ammeter reading with the front panel

ammeter reading. Or, compare the DVM reading with
the front panel ammeter reading using I = V/R, where
V is the DVM reading and R is the DC shunt

sistance.
e. Open output terminals and adjust VOLTAGE

controls for maximum output as required by the load
conditions.
If a load change causes the voltage limit to be
exceeded, the power supply will automatically cross
over to constant voltage output at the preset voltage
limit and output current will drop proportionately. In
setting voltage limit, allowance must be made for
high peak voltages which can cause unwanted
crossover.