Honeywell 5704

2-9
MAN0448_Issue 13_01-2010 5704 Control System
005704-M-5001 A03249
CHAPTER 2 - SYSTEM DESCRIPTION
4.2 Control Functions
The Four Channel Control Card carries out the control functions for up
to four loops of gas detection as follows:
a. Provides the necessary voltages and currents to drive the connected
sensors.
b. Processes the incoming sensor signals.
c. Displays the signal levels, one at a time, on the front panel liquid
crystal display.
d. Compareseachchannelsignallevelwithpre-denedalarmlimits.
e. Whenthepre-denedalarmlimitsareexceeded,raisesthealarms
by lighting up front panel LEDs and operating connected relays.
f. Informs other cards with the alarm status information.
g. Self validates the operation of its circuit components, software
operation and the condition of the sensor.
4.3 Analogue Output Module
OptionalAnalogueOutputModulesmaybefactoryttedtotheFour
Channel Control Card and are used on each channel of gas detection
to provide a current loop output which follows the sensor signal level.
This may be set electronically to produce a 0 - 20mA output or a 4 -
20mA output and can be used to operate a chart recorder, data logger,
PLC, etc. Two versions are available:
a. Analogue Output Module, Current Sink
Part Number 04200-A-0145
b. Analogue Output Module, Current Source
Part Number 04200-A-0146