![background image](http://html1.mh-extra.com/html/keithley/7038/7038_instruction-manual_3942242028.webp)
4-4
Center-to-shield isolation
Perform the following steps to check center-to-shield
isolation:
1. Connect the Model 6517A Electrometer to the center
conductor and shield output, as shown in Figure 4-3.
2. With the power off, install the Model 7038 card in the
mainframe.
3. Turn on the mainframe and the Model 6517A power,
and allow the electrometer to warm up for at least one
hour before making measurements. Make sure the volt-
age source is turned off.
4. Select the Model 6517A ohms function, choose the
2G
Ω
range, and make certain zero check is disabled.
5. Close channel 1 on the Model 7038.
6. Program the Model 6517A voltage source for 20V, and
make sure the internal voltage source connection mode
is selected.
7. Turn on the Model 6517A voltage source, and allow the
reading to settle.
8. Verify that the Model 6517A resistance reading is
>1G
Ω
.
9. Turn off the voltage source, and open channel 1.
Figure 4-2
Connections for channel isolation tests
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.
INPUT
250V PEAK
!
LINE RATING
50-60HZ
50VA MAX
AC ONLY
LINE FUSE
SLOWBLOW
1/2A 90-125V
1/4A 180-250V
IEEE-488
(CHANGE IEEE ADDRESS
WITH FRONT PANEL MENU)
DIGITAL
I/O
TRIG LINK
1
15V
LO
HI
RS232
!
MADE
IN
U.S.A.
PREAMP OUT
250 PEAK
COMMON
2V ANALOG
OUTPUT
TEMP
TYPE K
HUMIDITY
OPTION SLOT
V SOURCE
EXT TRIG
IN
MTR COMP
OUT
INTERLOCK
SELECTED
LINE VOLTAGE
90-110V
105-125V
180-220V
210-250V
1010V
PEAK
750V
PEAK
IN1
IN2
IN3
IN4
OUTA
IN5
IN6
IN7
IN8
OUTB
IN9
IN10
IN11
IN12
OUTC
Model 7038
Triax Cable
Connect voltage
source low
to card signal low
(connector shield)
Input
Voltage Source High
Model 6517 Electrometer
Note: Configure electrometer for
internal voltage source
connection.
Connect to connector shield
Connect to center conductor
SMB-to-BNC-to-Triax adapter
Содержание 7038
Страница 35: ......
Страница 36: ......
Страница 37: ......
Страница 38: ......
Страница 41: ...Keithley Instruments Inc 28775 Aurora Road Cleveland Ohio 44139 Printed in the U S A...