Kingfisher Plus+ Hardware Manual
the Analogue Input of the module and the third wire is connected to the module Ground pin
as illustrated below.
Self-Powered Analogue Device Connected to Analogue Input
Field Wiring
It is impossible to provide a practical guide for installation of equipment that covers all
possible real-world situations. However, some guidelines are suggested below.
To minimise capacitive loading and noise, all field connections to the module should be
wired to the I/O terminal board using a good grade of twisted, shielded instrumentation
cable.
Generally, the shield for inputs to a module should be grounded at the analogue source with
one point on the shield tied to the module as shown in the following figure.
Shield Connections for Analogue Inputs
For Analogue Outputs, the shield is normally grounded only at the source end (the module).
The shield connection provides access to the backplane (frame ground) resulting in superior
rejection of noise caused by any shield drain currents. In extreme noise environments, a
ground braid may be used to connect the frame ground on the base plate connector to earth
ground. This additional connection will bypass noise around the module. An internal link is
Hardware Manual Version 7.16
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