Keithley 7037, Инструкция по эксплуатации

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Service Information
6-13
Troubleshooting
WARNING
Lethal voltages are present within the
Model 7001/7002 mainframe. Some of
the procedures may expose you to haz-
ardous voltages. Observe standard
safety precautions for dealing with live
circuits. Failure to do so could result in
personal injury or death.
CAUTION
Observe the following precautions when
troubleshooting or repairing the card.
To avoid contamination, which could
degrade card performance, always han-
dle the card only by the handle and side
edges. Do not touch edge connectors,
board surfaces, or components on the
card. Also, do not touch areas adjacent
to electrical contacts on connectors.
Use care when removing relays from the
PC board to avoid pulling traces away
from the circuit board. Before attempt-
ing to remove a relay, use an appropri-
ate de-soldering tool, such as a solder
sucker, to clear each mounting hole
completely free of solder. Each relay pin
must be free to move in its mounting
hole before removal. Also, make certain
that no burrs are present on the ends of
the relay pins.
Troubleshooting equipment
Table 6-3 summarizes recommended equipment for trouble-
shooting the Model 7037.
Troubleshooting access
In order to gain access to the relay card top surface to mea-
sure voltages under actual operation conditions, perform the
following steps:
1. Disconnect the connector card from the relay card.
2. Remove the Model 7001/7002 cover.
3. Install the relay card in the CARD 1 slot location.
4. Turn on Model 7001/7002 power to measure voltages
(see following paragraph).
Table 6-3
Recommended troubleshooting equipment
Description
Manufacturer
and model
Application
Multimeter Keithley 2000 Measure DC voltages
Oscilloscope TEK 2243 View logic waveforms