System Sensor WFD20EXP Installation And Maintenance Instructions page 2

4. Seat the O-ring or gasket against the saddle and mount the detector di-
rectly to the pipe. Carefully roll the vane opposite the direction of flow
and insert it through the hole. Seat the saddle firmly against the pipe so
that the locating boss goes into the hole.
5. Install the U-bolt, tightening the nuts alternately to ensure a uniform
seal. See Table 1 for torque values.
6. Remove the metal cover with the tamper-proof wrench provided. Manu-
ally actuate the limit to check for binding. If the vane binds, remove the
detector and correct the cause before proceeding.
Be sure the direction-of-flow arrow points in the right direction or else water
flow will go unreported. See Figure 3.
fiGUre 1. moUnTinG dimensions:
4.019˝
5.019˝
U-BOLT
NUT
PIPE
SADDLE
U-BOLT
fiGUre 2. moUnTinG hoLe LocaTion:
WRONG
RIGHT
REMOVE BURRS FROM EDGE OF HOLE. CLEAN OUT SCALE
AND FOREIGN MATTER FROM INSIDE WALL OF PIPE.
TabLe 1:
Wfd Model Hole Size (in)
20, 25, 35
30-2, 40, 50, 60, 80
D770-24-00
CAUTION
6.75˝
PIPE
DIAMETER
PLUS 6.5˝
PIPE
PLASTIC
VANE
W0238-00
W0106-00
ToRque
1 1 / 30–35 ft.-lb.
4
2 55–60 ft.-lb.
firealarmresources.com
PreoPeraTion TesTinG
1. Fill the sprinkler system and check for leaks around the waterflow detec-
tor. If it leaks, first check for the proper torque on the U-bolt nuts. If the
leak persists, drain the system and remove the detector (refer to Mainte-
nance). Check for dirt or foreign objects under the gasket, and make sure
that the pipe surface is not dented. Reinstall the detector and check again
for leaks. Do not proceed until all leaks have been stopped.
2. Connect an ohmmeter or continuity tester across the COM and B-NO
switch terminals. The ohmmeter should indicate an open circuit.
3. Deflect the actuator lever and hold it until the pneumatic delay shaft
releases the switch buttons. The ohmmeter or continuity tester should
show a short circuit after the delay has elapsed. If there is no delay,
check the setting of the delay adjustment dial.
fiGUre 3. assembLY diaGram:
DELAY
MECHANISM
(REPLACEMENT P/N
A3008-00)
PIPE SADDLE
PLASTIC VANE
ROLL PADDLE (VANE)
OPPOSITE OF FLOW
ARROW WHILE INSERTING
SADDLE
GASKET
HOLE SIZE
(REFER TO TABLE 1)
WirinG
1. All models have two SPDT switches. Switch contacts COM and B-NO
are closed when water is flowing and open when it is not. Connect the
switches, as shown in Figure 4, depending on the application.
2. When connected to a listed sprinkler/fire alarm control panel, the initiat-
ing circuit must be non-silenceable.
3. A ground screw is provided with all waterflow detectors. When ground-
ing is required, clamp wire with screw in hole located between conduit
entrance holes. See Figure 3.
4. If a second conduit entry is required, remove the plug using a hex wrench.
High Voltage. Electrocution Hazard. Do not handle live AC wiring or work on a
device to which AC power is applied. Doing so may result in injury or death.
When utilizing switches at voltages greater than 74VDC
means to provide all–pole disconnection must be incorporated in the fixed
wiring, such as a circuit breaker.
2
COVER
TERMINAL BLOCK
(REPLACEMENT P/N A77-01-02)
GROUND
SCREW
(GREEN)
CONDUIT
ENTERANCE
U-BOLT NUT
DIRECTION OF
FLOW ARROW
U-BOLT
W0183-00
WARninG
or 49VAC
I56-1452-005R
PIPE