Performance and Calibration Procedures

Current Priority Constant Current Test

This test measures the change in output current resulting from a change in output voltage from about zero volts to the maximum output voltage.

NOTE: The voltage limits in Current Priority Mode are not programmable.

Action

Program Commands

1. Turn off the dc source and connect the output as shown in Figure B-1c

“*RST”

with an ammeter in series with a 16k ohm load resistor across the Hi

 

and Lo output terminals. Also connect a shorting switch across the

 

resistor.

 

2.Start with a short across the output (switch closed). Turn on the dc source and program the Current Priority mode. Program the current to the maximum value (0.5mA).

3.Set the ammeter to the 1A range, and record the output current reading on the ammeter (shorted-output value).

5.Remove the short from the output (open the switch).

6.Read back the N3280A status to be sure that it’s in the CC mode. This query should return a Bit value of “8” for CC mode.

7.Record the output current reading on the ammeter (full-load current value).

The difference between the two current readings is the Load Effect current and should be within the limits listed in the performance test record card for the appropriate model under Current Priority Load Effect Current.

“OUTP ON,(@1)” “SOUR:FUNC:MODE CURR,(@1)” “CURR 0.0005,(@1)”

“STAT:OPER:COND? (@1)”

Source Effect Tests

These tests measure the change in output voltage or current that results from a change in ac line voltage from the minimum to maximum value within the line voltage specifications. The tests should all be done at 60Hz line frequency.

Voltage Priority, Constant Voltage Source Effect

Action

Program Commands

1.Connect the ac input of the dc source to a variable voltage transformer (or ac source). Set the transformer to nominal line voltage.

Connect the output as shown in Figure B-1b with a 20 ohm resistor or an electronic load across the output terminals and a DVM across the Hi and Lo sense terminals.

2.Turn on the dc source, program the output voltage to the full-scale value (10.0V), and the current limit to the maximum value (0.5125A).

3.If you are using an electronic load, adjust it for the full-scale output current, 0.5A.

“OUTP ON,(@1)” “VOLT 10,(@1)” “CURR:LIM 0.5125,(@1)”

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Agilent Technologies N3280A manual Source Effect Tests, Current Priority Constant Current Test