Keithley 7035, Инструкция по эксплуатации

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Service Information
5-2
Performance verification
The following paragraphs discuss the performance verifica-
tion procedures for the Model 7035, including path resis-
tance, offset current, contact potential, and isolation.
CAUTION
Contamination will degrade the perfor-
mance of the card. To avoid contamina-
tion, always grasp the card by the side
edges or shields. Do not touch the con-
nectors and do not touch the board sur-
faces or components. On plugs and
receptacles, do not touch areas adjacent
to the electrical contacts.
NOTE
Failure of any performance verification
test may indicate that the card is contami-
nated. See the Handling and cleaning pre-
cautions paragraph to clean the card.
Environmental conditions
All verification measurements should be made at an ambient
temperature between 18
°
and 28
°
C and at a relative humidity
of less than 70%.
Recommended equipment
Table 5-1 summarizes the equipment necessary for perfor-
mance verification along with an application for each unit.
Multiplexer connections
The following information summarizes methods that can be
used to connect test instrumentation to the card. Detailed
connection information is provided in Section 3.
One method to make instrument connections to the multi-
plexer card is by hard-wiring a 96-pin female DIN connector
then mating it to the connector on the Model 7035. Input and
output shorting connections can also be done at the connec-
tor. The connector in the Model 7011-KIT-R connection kit
(Table 3-2) can be used for this purpose. Pin identification
for the connector is provided by Figure 3-1 and Table 3-1.
WARNING
When wiring a connector and device
under test, do not leave any exposed
wires or connections. No conductive
part of the circuit may be exposed. Prop-
erly cover the conductive parts, or death
by electric shock may occur.
CAUTION
After making solder connections to a
connector, remove solder flux as
explained in the Handling and cleaning
precautions paragraph. Failure to clean
the solder connections could result in
degraded performance and prevent the
card from passing verification tests.
Before pre-wiring any connectors or plugs, study the follow-
ing test procedures to fully understand the connection
requirements.
Table 5-1
Verification equipment
Description Model Specifications Applications
DMM Keithley Model 2000 100
Ω
; 0.01% Path resistance
Electrometer w/voltage source Keithley Model
6517A 20pA, 200pA; 1%
100V source; 0.15% Offset current, path isolation
Sensitive Digital Voltmeter Keithley Model 182 3mV; 60ppm Contact potential
Triax cable (unterminated) Keithley Model 7025
⎯
Offset current
Low thermal cable
(unterminated) Keithley Model 1484
⎯
Contact potential