Rapidrop RDWFDN Manual

IOM 2.40
Issue A
Water Flow Detector
Fig. RDWFDN
Important
This instruction manual contains important information about the
installation and operation of waterflow detectors. Purchasers who
install waterflow detectors for use by others must leave this manual
or a copy of it with the user.
Read all instructions carefully before beginning. Follow only those
instructions that apply to the model you are installing.
Caution
The model RDWFDN is a vane-type waterflow detector for use in
wet-pipe fire sprinkler systems only. Vane-type waterflow detectors
shall not be used as the sole initiating device in both deluge and
preaction systems; waterflow detectors used in these types of
systems may result in an unintended discharge caused by a surge,
trapped air or a short retard time.
Do NOT use any of the RDWFDN models on copper pipe. The
clamping forces of the mounting bolts may collapse the pipe
sufficiently to prevent the detector from functioning properly.
Do NOT install steel or iron pipe sections in copper piping for
mounting a waterflow detector. Incompatibility between the
dissimilar metals causes bimetallic corrosion.
Warning
Installation must be performed by qualified personnel and in
accordance with all national and local codes and ordinances.
Shock hazard: Disconnect power source before servicing. Serious
injury or death could result.
Risk of explosion: Not for use in hazardous locations. Serious injury or
death could result.
Principles of Operation
Vane-type waterflow detectors mount to water-filled pipes in fire
sprinkler systems. Waterflow in the pipe deflects a vane, which
produces a switched output, usually after a specified delay. All
RDWFDNs have a pneumatically controlled mechanical delay
mechanism. Delays do NOT accumulate; they reset if the flow of
water stops or drops below minimum triggering flow rate before the
entire delay has elapsed.
All switches actuate when the waterflow rate is 10 gallons per minute
or greater, but will not actuate if the flow rate is less than 4 gallons
per minute. This Rapidrop installation manual covers the following
waterflow detectors for fire sprinkler/fire alarm applications.
IOM: 2.40
Issue A
05/04/2024
© 2024 Rapidrop
Rapidrop Global Ltd reserves the right to change the design, materials and specifications without notice to continue product development
Rapidrop Global Ltd
T: +44 (0) 1733 847 510 F: +44 (0) 1733 553 958
e: rapidrop@rapidrop.com
w: www.rapidrop.com
Specification
Max. Working Pressure
Contact Ratings
Triggering Threshold
Bandwidth
Dimensions
Operating Temperature
Range
Steel water pipe, schedule 7 through 40 (See
Compatible Pipe
Shipping Weight
Enclosure Rating
Sizes
Model
mm
RDWFD20N DN50
RDWFD25N DN65
RDWFD30N DN80
RDWFD40N DN100
RDWFD50N DN125
RDWFD60N DN150
RDWFD80N DN200
FM
31 bar (450 psi)
10A @ 125/250V AC, 2.5A @24V DC
4 to 10 gpm
66 × 88.9 × 170 mm
(2.6˝ H × 3.5˝ W × 6.7˝ D)
0°C to 66°C (32°F to 150°F)
chart below)
1.3 to 2.7kg (3 to 6lbs) depending on size
NEMA Type 4, as tested by UL
Pipe Size
Pipe Schedule
in
2" 7 thru 40
2 1/2" 7 thru 40
3" 7 thru 40
4" 7 thru 40
5" 10 thru 40
6" 10 thru 40
8" 10 thru 40
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