3.3.1
Resistance Programming Current Mode (Figure 3-6)
OCR-B supplies may be programmed externally to provide output current. This
is done. by inserting a fixed or variable resistance into the current mode amplifier
reference circuit. The programming resistor selected should have a low tempera
ture coefficient (±30 ppm) and should dissipate approximately 0.5 milliwatt. Pro
gramming current is approximately 1. 0 milliampere.
TB 1
Figure 3-6 Current Mode Programming Connections
To adapt unit to the current mode, resistance programming configuration, proceed
as follows:
1.
With unit power OFF, remove the link between terminals 7 and 8, and
rotate VOLT AGE controls to mid position.
2 .
Insert programming resistor between terminals
8
and
9 .
3.
Adjust COARSE VOLTAGE control until unit voltmeter indicates desired
voltage limit value.
4.
Set POWER switch to OFF and connect load leads to output terminals.
Observe Polarity.
5.
Set POWER switch to ON.
POWER and CURRENT mode indicators will
illuminate.
Operation
3-9
Rev B (6/84)
