Keysight N6705 Service Manual page 21

Model N6705 Service Guide
5
Adjust the AC input to the lowest rated line voltage (86 VAC).
6
Divide the voltage drop (DMM reading) across the current
monitoring resistor by its resistance to convert to amps and record
this value (Iout).
7
Adjust the AC input to the highest rated line voltage (264 VAC).
8
Divide the voltage drop (DMM reading) across the current
monitoring resistor by its resistance to convert to amps and record
this value (Iout). The difference between the DMM reading in steps 6
and 8 is the source effect, which should not exceed the value listed
in the test record for the appropriate model under "CC Source
Effect".
Resistance Programming Accuracy (N6781A and N6785A only)
Test category = performance, calibration
Note: Current readback accuracy must be verified prior to this test.
1
Connect an external DMM and an electronic load directly to the
output (see Test Setup F). Turn on the DC Power Analyzer.
2
Set the 20 V range and program the output to 10 V. Turn the output
on and record the voltage reading on the DMM. This is the voltage
with no load (Vnl).
3
Program the output resistance to 1 ohm. Turn on the electronic load.
Select CC mode, current: 1 A, Input On.
4
Record the voltage reading on the DMM. This is the voltage with a
load (Vwl). Record the current reading on the front panel of the DC
Power Analyzer. This is the current with a load (Iwl).
5
Calculate the resistance value as follows: R = (Vnl−Vwl)/Iwl
This is the output resistance, which should not exceed value listed in
the test record under "Resistance Programming".
6
For N6781A, repeat steps 2 through 5 for the 6 V range. Set the
output voltage to 6 V and the load current to 3 A.
Negative Current Output (N6783A-BAT and -MFG only)
Test category = performance, calibration
1
Connect the DMM, current shunt, and a power supply to the output
(see Test Setup G). Connect plus to plus, minus to minus. Set the
external power supply to 3V, 3A.
2
Set the N6783A power module to the values indicted in the test
record under "Negative Current Output". The display should read
approximately -2 A.
3
Divide the voltage drop (DMM reading) across the current shunt by
its resistance to convert to amperes and record this value. The
reading should be within the limits specified on the test record under
Constant Current Tests, "Negative Current Output".
Performance Verification 2
21