12.4 4 - 20Ma Transmitter Connections - Honeywell 5704 Operating Instructions Manual

MAN0448_Issue 13_01-2010
005704-M-5001 A03249
CHAPTER 4 - INSTAllATION INSTRUCTIONS

12.4 4 - 20mA Transmitter Connections

Transmitters require either three or four wire connections and the sensor
documentation will indicate the 0V and +24V power connections and
the positive and negative loop connections.
At the System 57 end of the field cable the sensor loop signal wires
should be connected to the S, 01, NS terminals on the Quad Relay
Interface Card that is attached to the required Four Channel Control
Card. The exact terminals used vary depending upon whether three or
four wire topology is used, the requirement for a loop current source
configuration and the channel to be connected to.
The transmitter power connection +24V and 0V should be connected
to a suitable dc supply.
Note: Terminals 35 and 36 on the Relay Interface Card are input terminals
only and cannot be used to power the transmitter.
The sensor cable screen or steel wire armour (or braid), as appropriate,
should be connected to the system (protective) earth. This can be
achieved where the cable enters the cabinet by using a metal cable
gland, or by other suitable means, and avoiding any screen 'tails' within
the cabinet.
Where the cable consists of a separate screen sheath and wire armour
(or braid), the armour should be connected, at the cabinet entry, to the
protective earth and the screen sheath should be connected to the
GROUND terminal of the Quad Relay Interface Card or to a suitable
instrument earth point.
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5704 Control System