User manual

47
6.5 RESISTIVE PROGRAMMING OF OUTPUT VOLTAGE AND CURRENT LIMIT
For resistive programming, internal current sources, for output voltage and/or output current 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 0~5Kohm or 0~10Kohm can be selected to program the output voltage and
current limit from zero to full scale.
A variable resistor can control the output over its entire range, or a combination of variable resistor
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 SW1-1 to its UP position for output voltage external programming and
SW1-2 to its UP position for Output Current limit external programming.
3. Set SW1 position 3 to select programming resistor range according to Table 6-4.
4. Set SW1-7 to its UP position for output voltage resistive programming and
SW1-8 to its UP position for Output Current limit resistive programming.
5. Connect a short between J1-8, J1-12 and J1-23 (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.
Adjust the resistors to change the power supply output.
1. SW1 positions 4, 5, 6 and 9 are not required for remote programming. Their setting can be
determined according to the application requirements.
2. The control circuits allow the user to set the output voltage and current limit 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 current
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 communication
port) of output voltage and current are disabled.
NOTES:
SW1-3 setting
UP
DOWN
Output Voltage programming
VPGM (J1-9)
0-10Kohm
0-5Kohm
Current limit programming
IPGM (J1-10)
0-10Kohm
0-5Kohm
Table 6-4: SW1-3 setting and programming range
47
1
14
13
25
10 9
23
22
CURRENT LIMIT
PROGRAMMING
OUTPUT VOLTAGE
PROGRAMMING
J1 connector, rear panel view
Fig.6-2: Remote resistive programming
PROGRAMMING
RESISTOR
PROGRAMMING
RESISTOR
OPTIONAL SETS
LOWER LIMIT
OPTIONAL SETS
LOWER LIMIT
OPTIONAL SETS
UPPER LIMIT
OPTIONAL SETS
UPPER LIMIT
12
8