Flow fault circuit, Flow fault contacts – Detcon 971-042200-00L User Manual
Page 4
Caution: Observe correct polarity when terminating all input/output wiring. Failure to do so may result in circuit dam-
age on power up. Seethe field wiring diagram below for terminal locations.
4. Connect 220VAC to the connector labeled “220VAC IN”.
5. If applicable, connect 24 VDC battery backup to the connector labeled “24 VDC IN”.
6. If applicable, connect a remote recording device or computer to the 4-20 mA signal output connector. The terminals
are labeled SENSOR “–” and “mA”.
8. If applicable, connect flow fault alarm wiring. Two sets of form C contacts (common, normally open and normally
closed) are provided. Relay contacts are rated 1 amp at 30VDC/.24 amp at 125VDC.
1
1..2
2 S
ST
TA
AR
RT
T U
UP
P
Upon completion of all tubing connections and field wiring turn on the power switch located on the enclosure door.
Note that the power lamp illuminates. If applicable, note that the sensor LCD indicators activate. Varying readings may
occur during sensor warm-up. Allow approximately 1 hour to stabilize (24 hours is best).
Also note air flow through the flow meter. Adjust the flow meter as necessary so that it falls between 500 and 1000
ml/m (milli liters per minute).
Assure that all field tubing connections are secure by obstructing the end of the sample line and observing that the
flow meter decreases to “0” flow.
Detcon Model 971-042200-00L Gas Detection System PG.4
P7
P6
P4
L2 NEU GND
mA
220 VAC
IN
24 VDC
IN
Battery
Backup
SENSOR #1
Flow
Fault
Circuit
COM
NO
NC
1
COM
NO
NC
2
COM
NO
NC
3
PT1
mA
4-20mA
Wire th 4-20mA output signal to
the plug-type connnector
Wire 220 VAC & optional 24 VDC
backup to the lugless connectors.
Two discreet form C dry contacts are provided (2 & 3) by the
flow fault circuit for alarm devices. The first set of contacts
(1) are prewired to interrupt the 4-20mA signal output in the
event of a flow fault. This will allow for flow fault monitoring
at any controller/computer that the signal is wired in to.
L1
FLOW
FAULT
CONTACTS