Specifications

36
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Reduced Pressure Principle with Integral Relief Valve Battery
Monitor Switch 975XLBMS Series Pat. No. 5,425,393
• 3/4”, 1”, 1
1
/
4
”, 1
1
/
2
”, 2”
• Reduced pressure principle backflow preventer with self-contained
battery powered switch
• In the event of a backflow condition the 975XLBMS sounds an audible
alarm signaling that a possible relief valve discharge may be occurring
• Features manual on/off switch and LED indicating battery charge
• Built-in delay to prevent false signal due to intermediate pressure
fluctuations
• Bronze body and cover construction
• Spring-loaded, center guided check valves
• Noryl
®
replaceable seats
• Entire unit serviceable in line
• Temperature range 33°F – 180°F
• Maximum pressure 175 psi
• UL
®
recognized switch – supplied with normally open contacts
• Switch is factory installed and ready for immediate installation to appropriate
electrical circuit
• With BSP threaded connections
• Self-contained monitor switch is also available as a kit to retrofit existing
975XL installations
• ASSE
®
Listed 1013, IAPMO
®
Listed, AWWA, CSA
®
Certified
• Approved by the Foundation for Cross-Connection Control and
Hydraulic Research at the University of Southern California
Model 975XLBMS FNPT x FNPT end connections
Model 975LXLBMS Less shut-off valves
Model 975XLBMSS Supplied with bronze wye strainer
Model 975XLBMSU Union connections between ball valves and
the device
Model BVMS Supplied with ball valve monitor switch
For Additional Information, reference WK-BPC catalog or visit
our web site.
OptionsTypical Installation Features
Relief valve discharge from a reduced pressure principle assembly can lead to costly water
damage. The 975XLBMS is designed to sound an audible alarm should the relief valve begin
to discharge. The battery monitor switch used with the 975XLBMS is a stand-alone alarm that
does not require electrical power. When the relief valve discharge occurs, the BMS’s internal
timer will set off an audible alarm within 10 seconds, letting the appropriate people know that
discharge is occurring. In addition to this feature, the BMS also exhibits a phone port that can
be connected to an auto dialer or alarm panel.
 Air gap (Model AG)
 Thermal expansion tank (Model XT)
 Soft seated check valve (Model 40XL)
Local codes shall govern installation requirements. To be installed in accordance with the manufacturers’ instructions and the latest edition of the
Uniform Plumbing Code. Unless otherwise specified, the assembly shall be mounted at a minimum of 12” (305mm) and a maximum of 30” (762mm)
above adequate drains with sufficient side clearance for testing and maintenance. Note: If installed outdoors, a protective enclosure is recommended.
The installation shall be made so that no part of the unit can be submerged.
 Water hammer arrestor (Model 1250)
 Quick test set (QT-SET)
 Test cock lock (Model TCL24)
Accessories Applications
BATTERY
MONITOR
SWITCH
AIR GAP
FITTING
12" MIN.
MODEL 975XLBMS
30" MAX.
FLOOR DRAIN
DIRECTION OF FLOW
FLOOR
CENTRAL
STATION
ALARM
PANEL
Backflow Preventers