Keithley 7037, Инструкция по эксплуатации

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Service Information
6-4
Offset current tests
These tests check leakage current from input (IN) and output
(OUT) to chassis (common mode) for each channel. In gen-
eral, these tests are performed by simply measuring the leak-
age current with an electrometer. In the following procedure,
the Model 6517A is used to measure leakage current.
Referring to Figure 6-2, perform the following procedure to
check offset current:
1. Turn off the Model 7001/7002 if it is on.
2. Connect the Model 6517A electrometer to channel 1 as
shown in Figure 6-2. Note that electrometer HI is con-
nected to input (IN) of channel 1. Electrometer LO is
connected to chassis ground, which is accessible at the
rear panel of the mainframe.
3. Install the Model 7037 card in slot 1 (CARD 1) of the
Model 7001/7002 if it is not already installed.
4. On the Model 6517A, select the 200pA range and
enable zero check and zero correct the instrument.
Leave zero correct enabled for the entire procedure.
5. Turn on the Model 7001/7002.
6. Program the Model 7001/7002 to close channel 1!1.
7. On the Model 6517A, disable zero check and verify that
it is <100pA. This measurement is the common-mode
leakage current of the channel.
8. On the Model 6517A, enable zero check.
9. Repeat the basic procedure in steps 1 through 8 to check
the other channels. Remember to close the channel that
the electrometer is connected to.
Figure 6-2
Offset current testing
WARNING:
NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
WARNING:
NO INTERNAL OPERATOR SERVICABLE PARTS,SERVICE BY QUALIFIED PERSONNEL ONLY.
CAUTION:
FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
CAUTION:
FOR CONTINUED PROTECTION AGAINST FIRE HAZARD,REPLACE FUSE WITH SAME TYPE AND RATING.
!
115V
!
90-110V
105-125V
180-220V
210-250V
7037
IN
OUT
Each Channel:
Model 6517A
(Measure Current)
Model 7025
Unterminated
Triax Cable
HI
LO
Chassis ground can be
accessed at the rear
panel of the 7001/7002