semaphore KINGFISHER PLUS+ Hardware Reference Manual page 145

Kingfisher Plus+ Hardware Manual
Analogue outputs 1 & 2 and analogue outputs 3 & 4 form two groups that are isolated from
each other and from the backplane logic. Each group is powered by a separate DC-DC
converter module that produces an isolated voltage of +24 V to drive the current loop
outputs and analogue front-end.
The current loop drivers on the module are source type drivers. To minimize the capacitive
loading and noise, all field connections to the module should be wired using a good grade of
twisted, shielded instrumentation cable. The shields should be connected to E (Shield) on
the user terminal connector block. The E connection provides path to the backplane (frame
Earth / Ground) resulting in attenuation of noise caused by the shield drain currents. To
further improve noise immunity, direct connection of the analogue cable shields to the Earth /
Ground rails with metal clamps or similar method is recommended, especially in
environments with high electromagnetic noise levels.
This module can be installed in any I/O slot of a 4, 6 or 12 slot backplane in a system. Up to
10 Analogue output modules can be installed on a single 12-slot backplane.
AO-3 configuration link location
Hardware Manual Version 7.16 http://www.servelec-semaphore.com/ Page 145