Direct Method; General Wiring Methods For Analog Modules; Analog Input Module Wiring Methods; Using A Generic Terminal Block Or Strip - GE 90-30 PLC Series Installation And Hardware Manual

Direct Method

General Wiring Methods for Analog Modules

Twisted, shielded instrumentation cable is strongly recommended for analog module input or
output signal connections. Proper grounding of the shield is also important. For maximum
electrical noise suppression, the cable shield should only be grounded at one end of the cable. For
Input modules, ground the end that is in the noisiest environment (which often is at the field device
end). For Output modules, ground at the module end. See GFK-0898, Series 90-30 PLC I/O
Module Specifications, for more shield grounding information.

Analog Input Module Wiring Methods

Correcting electrical noise problems can sometimes be a trial-and-error routine. However, in
general, it is generally best to ground the cable shield as close to the source of the noise as possible,
which is usually at the device end. In troubleshooting noise problems, sometimes it is beneficial to
experiment with the shield grounding point location. Remember, the cable shield should be
grounded at one end only. Also, it is best to keep the length of stripped cable leads as short as
possible to minimize the length of unshielded conductors that will be exposed to the noisy
environment. See the Series 90-30 PLC I/O Module Specifications Manual, GFK-0898 for
additional details.

Using a Generic Terminal Block or Strip

Direct Method
GFK-0356Q Chapter 2 Installation
Connect an IC693CBL327/328 cable, or a custom made cable, to the module's faceplate
connectors, and wire the stripped ends of the cable directly to the field devices. See Chapter
10 for cable data. See the Series 90-30 PLC I/O Module Specifications Manual, GFK-0898,
for pin-out information.
Mount a terminal strip inside the control enclosure and run a shielded cable from the terminal
strip to each input circuit on the module's terminal board terminals.
Connect each cable's shield to the metal panel next to the terminal strip. Do not connect the
shields at the module end (cut shield off at module end of cable and insulate with shrink
tubing).
Wire the field device to the terminal strip with a shielded cable, grounding the shield at the
device end only (cut shield off at terminal strip end of cable and insulate with shrink tubing).
Also, keep the length of exposed (outside of shield) leads at the terminal strip and device ends
as short as possible.
Run a shielded cable from the field device (transducer, potentiometer, etc.) directly to the
module.
Connect the conductors to the applicable screws on the module's terminal board.
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