System Sensor WFD Series Installation And Maintenance Instructions page 2

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 2 for torque values.
6. Remove the metal cover with the tamper-proof wrench provided. Move
the actuator lever back and forth 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.
Preoperation Testing
1. Fill the sprinkler system and check for leaks around the waterflow
detector. 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 Maintenance). Check for dirt or foreign objects under the
gasket, and make sure that the pipe surface is not dented. Rein-
stall 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
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.
Wiring
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.
1. All models have two SPDT switches. Switch contacts COM and B 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 initi-
ating circuit must be nonsilenceable.
3. A ground screw is provided with all waterflow detectors. When
grounding is required, clamp wire with screw in hole located between
conduit entrance holes. See Figure 5A, page 4.
4. If a second conduit entry is required, remove the knockout plug using
a flat blade screwdriver as shown on Figure 5B, page 4. Strike sharply
with a hammer to pierce the wall of the knockout plug. Move to an
adjacent wall section and repeat until the plug falls out. Make sure that
the waterflow detector is supported adequately during this operation
to avoid injury.
Mechanical Delay Adjustment
The pneumatic delay is preset at the factory to dial setting 2. To adjust the
setting, turn the adjustment dial clockwise to increase the delay, counter-
clockwise to decrease it. The delay is adjustable from 0 to 70 seconds. See
Figure 6, page 4.
NOTE: Set the delay to the minimum required to prevent false alarms
from flow surges.
After extended service, parts of the detector may become worn, reducing
the delay time and causing false alarms. If this happens, increase the de-
lay. If the delay is already at the maximum, replace the mechanical delay
assembly. Refer to Maintenance for ordering replacement parts.
D770-01-00
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CAUTION
WARNING
Figure 1. Mounting dimensions:
3"
U-bolt nut
Pipe saddle
U-bolt
Overall width = pipe diameter + 3"
Figure 2. Mounting hole location:
Remove burrs from edge of hole. Clean out scale and foreign
matter for one pipe diameter on each side of hole.
Table 1:
WFD MODEL*
20, 25, 30, 35
30-2, 40, 50, 60, 80
Table 2:
WFD MODEL*
20, 25, 30, 35
30-2, 40, 50, 60, 80
*See model listing on page 1 for pipe sizes.
2
3-3/4"
Pipe diameter
plus 5-1/4"
Pipe
Plastic vane
A78-1609-00
Wrong
Right
A78-1496-01
HOLE SIZE
1-1/4"
2"
TORQUE
30-35 ft.-lb.
55-60 ft.-lb.
I56-459-11