Keithley 2000-SCAN-20, Инструкция по эксплуатации

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2-2 Card Connections and Installation
Introduction
WARNING The procedures in this section are intended only for qualified service
personnel. Do not perform these procedures unless you are qualified to do
so. Failure to recognize and observe normal safety precautions could result
in personal injury or death.
This section includes information on making connections to the Model 2000-SCAN-20 and
installing the card in a Model 2000-20 Multimeter. This section is arranged as follows:
•
Handling precautions —
Explains precautions that must be followed to prevent
contamination to the scanner card assembly. Contamination could degrade the
performance of the scanner card.
• Connections — Covers the basics for connecting external circuitry to the scanner card.
•
Typical connection schemes —
Provides some typical connection schemes for 2-pole
and 4-pole operation.
• Card installation and removal — Summarizes the procedure to install the scanner card
in a multimeter, outlines scanner card output connections, and describes how to remove
the card.
Handling precautions
To maintain high impedance isolation between channels, take care when handling the scanner
card to avoid contamination from such foreign materials as body oils. Such contamination can
substantially lower leakage resistances and degrade card performance. To avoid possible
contamination, always grasp the scanner card by the side edges. Do not touch board surfaces,
components, or areas adjacent to electrical contacts.
Dirt buildup over a period of time is another possible source of contamination. To avoid this
problem, operate the multimeter and scanner card in a clean environment. If the card becomes
contaminated, thoroughly clean it as explained in
Section 4 .