Keithley 2701, Service Manual

Page: 36 / 168

1-22 Performance Verification Model 2701 Service Manual
Verifying DC current
Check DC current accuracy by applying accurate DC currents from the DC current calibra-
tor to the input terminals of the Model 7700 and verifying that the displayed readings fall
within specified limits.
Follow these steps to verify DC current accuracy:
1. Connect the Model 7700 CH21 H and L terminals to the calibrator as shown in
Figure 1-10 .
Figure 1-10
Connections for Model 7700 DC current verification
H L H L
AMPS
H L H L H L H L H L H L
LO
CH21 CH22 CH11 CH12 CH13 CH14 CH15 CH16
H L H L H L H L
CH17 CH18 CH19 CH20
SENSE
(OHMS, 4 WIRE)
INPUT
(V, 2 WIRE)
H L H L H L H L
CH7 CH8 CH9 CH10
H L H L H L H L
H L H L H L H L
INPUT SENSE CH1 CH2
CH3 CH4
CH5 CH6
CH21
Output HI
Output
LO
Calibrator (Output DC Current)
Note: Be sure calibrator is set for
normal current output.
Model 7700