Keithley 2790, Reference Manual

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Model 2790 SourceMeter
®
Switch System Reference Manual 16-23
Verifying AC current
Check AC current accuracy by applying accurate AC voltage current at specific frequen-
cies from the AC current calibrator to the Model 7702 input terminals and verifying that
the displayed readings fall within specified limits. Follow these steps to verify AC current:
1. Connect the Model 7702 CH41 H and L terminals to the calibrator as shown in
Figure 16-11 .
Figure 16-11
Connections for Model 7702 AC current verification
2. Install the Model 7702 in Slot 1 of the Model 2790, then turn on the power and
allow the unit to warm up for two hours before proceeding. Be sure the front panel
INPUTS switch is set to the REAR position.
3. Select the AC current function by pressing the ACI key.
4. Set the Model 2790 for the 1A range. Close Channel 41 by pressing the CLOSE
key and keying in 141.
5. Source 1A and 3A, 1kHz full-scale AC currents as summarized in Table 16-11 and
verify that the readings are within stated limits.
6. Press the OPEN key to open Channel 41.
Table 16-11
Model 7702 ACI limits
ACI range
Applied
AC current
Reading limits @ 1kHz
(1 year, 18°C to 28°C)
1A
3A 1.000000A
3.00000A* 0.99860 to 1.00140A
2.9937 to 3.0063A
* If the Fluke 5725A amplifier is not available, apply 2.2A from the calibrator.
Reading limits for 2.2A are 2.1949 to 2.2051A.
TE122
TE121
CH41
OUTPUT
HI
OUTPUT
LO
Calibrator (Output AC Current)
Model 7702