83-507-5002 Rev. B
48
6.5 RESISITIVE PROGRAMMING OF OUTPUT VOLTAGE AND CURRENT LIMIT
For resistive programming, internal current sources, for Output Voltage and/or Output Curr ent
control, supply 1mA current through external programming resistors connected between J1-9 &
22 and J1-10 & 23. The voltage across the programming resistors is used as a programming
voltage for the power supply. Resistance of 0i5Kohm or 0i10Kohm can be selected to program
the Output Voltage and Output Current from zero to full scale.
A variable resistor can control the output over its entire range, or a combination of variable resis-
tor and series/parallel resistors can control the output over restricted portion of its range.
Perform the following procedure to set the power supply to Resistive programming:
1. Turn the AC On/Off switch to Off.
2. Set setup switch SW1, positions 1 and 2 to their UP position.
3. Set SW1, position 3 to select the programming resistor range according to Table 6-4.
4. Set SW1, positions 7 and 8 to their UP position, to enable resistive programming mode.
5. Connect a wire jumper between J1-8 and J1-12 (refer to Table 4-4).
6. Connect the programming resistors to the mating plug of J1 as shown in Fig.6-2.
7. Set the programming resistors to the desired resistance and turn the power supply ON. Ad-
just the resistors to change the power supply output.
NOTES:
1. SW1, positions 4, 5, 6 and 9 are not required for remote programming. T heir settings can be
determined according to the application requirements.
2. The control circuits allow the user to set the Output Voltage and Output Current up to 5%
over the model-rated maximum value. The power supply will operate within the extended
range, however it is not recommended to operate the power supply over its voltage and cur-
rent rating and performance is not guaranteed.
3. To maintain the temperature stability specification of the power supply, the resistors used for
programming should be stable and low noise resistors, with temperature coefficient of less
than 50ppm.
4. When resistive programming is used, front panel and computer control (via serial communi-
cation port) of Output Voltage and Current are disabled.
SW1-3 setting Output Voltage programming
VPGM (J1-9) Output Current programming
IPGM (J1-10)
UP 0-10Kohm 0-10Kohm
DOWN 0-5Kohm 0-5Kohm
Table 6-4: SW1-3 setting and programming range
1
14
13
25
10 9
23 22
OUTPUT CURRENT
PROGRAMMING OUTPUT VOLTAGE
PROGRAMMING
J1 connector, rear panel view
Fig.6-2: Remote resistive progra mming
PROGRAMMING
RESISTOR
PROGRAMMING
RESISTOR
OPTIONAL SETS
LOWER LIMIT
OPTIONAL SETS
LOWER LIMIT
OPTIONAL SETS
UPPER LIMIT
OPTIONAL SETS
UPPER LIMIT
12 8