Keithley 7037, Инструкция по эксплуатации

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6
Service Information
6-1
WARNING
The information in this section is
intended only for qualified service per-
sonnel. Some of the procedures may
expose you to hazardous voltages that
could result in personal injury or death.
Do not attempt to perform these proce-
dures unless you are qualified to do so.
Introduction
This section contains information necessary to service the
Model 7037 relay-digital I/O card and is arranged as follows:
•
Handling and cleaning precautions  Discusses han-
dling procedures and cleaning methods for the card.
•
Performance verificatio  Covers the procedures
necessary to determine if the card is operating properly.
•
Channel functionality test  Provides a test proce-
dure to determine if a digital I/O input or output channel
is functioning properly.
•
Special handling of static-sensitive devices  Re-
views precautions necessary when handling static-sen-
sitive devices.
•
Principles of operation  Briefly discusses circuit op-
eration.
•
Troubleshooting  Presents some troubleshooting
tips for the card.
Handling and cleaning precautions
Because of the high impedance circuits on the Model 7037,
care should be taken when handling or servicing the card to
prevent possible contamination that could degrade perfor-
mance. The following precautions should be taken when
handling the card.
Do not store or operate the card in an environment where
dust could settle on the circuit board. Use dry nitrogen gas to
clean dust off the card if necessary.
Handle the card only by the side edges and shields. Do not
touch any board surfaces, components, or connectors. Do not
touch areas adjacent to electrical contacts. When servicing
the card, wear clean cotton gloves.
If making solder repairs on the circuit board, use an
OA-based (organic activated) flux. Remove the flux from
these areas when the repair is complete. Use pure water
along with plenty of clean cotton swabs to remove the flux
Take care not to spread the flux to other areas of the circuit
board. Once the flux has been removed, swab only the
repaired area with methanol, then blowdry the board with
dry nitrogen gas.
After cleaning, the card should be placed in a 50 ° C low
humidity environment for several hours.