System Sensor WFD20A Installation Instruction page 3

figUre 4. WfDa Wiring:
WIRE CODE:
WATERFLOW OR SUPERVISORY SWITCH:
COM TO B-NO = OPEN CIRCUIT
COM TO A-NC = CLOSED CIRCUIT
COVER TAMPER SWITCH:
BLACK/BLUE: OPEN
BLACK/RED: CLOSED
NOTE: COMMON AND B-NO
CONNECTIONS WILL CLOSE WHEN VANE
IS DEFLECTED, I.E., WHEN WATER IS
FLOWING. DUAL SWITCHES PERMIT
APPLICATIONS TO BE COMBINED ON A
SINGLE DETECTOR.
TOP VIEW
figUre 5a. groUnD screW LocaTion:
MOUNTING PLATE
figUre 5b. KnocKoUT pLUg removaL:
mechanicaL DeLaY aDjUsTmenT
The pneumatic delay is preset at the factory to 30 seconds. To adjust the set-
ting, turn the adjustment dial clockwise to increase the delay, counterclockwise
to decrease it. The delay is adjustable from 0 to 90 seconds. See Figure 6.
NOTE: Set the delay to the minimum required to prevent false alarms from
flow surges.
D770-44-00
WIRE
NUT
RED
(NON-ALARM
CONDITION)
(COVER OFF)
TO NONSILENCEABLE
INITIATING ZONE OF
LISTED FACP
BREAK WIRE AS SHOWN FOR
SUPERVISION OF CONNECTION.
DO NOT ALLOW STRIPPED WIRE
LEADS TO EXTEND BEYOND
SWITCH HOUSING. DO NOT
LOOP WIRES.
GROUND
SCREW
(GREEN)
TYPICAL FIRE ALARM CONTROL PANEL CONNECTION
BLUE
NC
NO
COM
BLACK
COM COM
B-NO
A-NC B-NO A-NC
COVER
TAMPER
SWITCH
TO POWER
SOURCE
COMPATIBLE
WITH BELL
NOTE: LOCAL BELL WILL ACTIVATE WHEN COVER IS REMOVED.
After extended service, parts of the detector may become worn, reducing the
delay time and causing false alarms. If this happens, increase the delay. If
the delay is already at the maximum, replace the mechanical delay assembly.
Refer to Maintenance for ordering replacement parts.
figUre 6. DeLaY aDjUsTmenT DiaL:
DELAY
ADJUSTMENT
DIAL
W0137-00
W0148-01
NOTE: RETARD TIME MAY EXCEED 90 SECONDS. ADJUST
AND VERIFY THAT TIME DOES NOT EXCEED 90 SECONDS.
NUMBER ON DIAL IS APPROXIMATE TIME DELAY IN
SECONDS WITH AN ACCURACY OF +/− 50%.
3
RED
NC
NO
WIRE COM
NUT
BLUE BLACK
COM
A-NC B-NO B-NO A-NC
TYPICAL LOCAL BELL CONNECTION
RED
NC
BLUE
NO
COM
BLACK
B-NO A-NC
COM
45
END-OF-LINE
RESISTOR
COM
WIRE
NUT
LOCAL
BELL
W0134-01
W0112-02
I56-2338-004R