The Model VSR-S is a vane type waterflow switch for use on wet sprinkler systems that use 1" (25mm), 1¼" (32mm), 1½" (38mm) or 2" (50mm) pipe size. The unit may also be used as a sectional waterflow detector on large systems.

Unique Features

Codes and Approvals

Engineering Specifications

Small Pipe Waterflow Alarm Vane Switches: UL Listed waterflow alarm switches shall be furnished and installed at each sprinkler system branch line connection to the wet pipe main where indicated on the drawings, and as required by NFPA Standards. Mounting shall be by means of a 1 inch TEE fitting installed in the branch line. Vanes shall be field installed on the switch from a selection supplied with the switch and fit pipe sizes 1 inch through 2 inches. Waterflow switches shall be capable of operation in system pressures up to 300 PSI, maximum surges of up to 18 FPS and alarm activation at 10 GPM. Switch configuration shall consist of two sets of single pole double throw (S.P.D.T.) Form C synchronized sets of contacts rated at 10A, 125 VAC and 2A, 30 VDC. Switch enclosure shall meet NEMA 4 rating and shall be equipped with an instantly recycling adjustable retard with a 0-90 second range. Enclosure cover shall be held captive by tamper resistant screws or supervised for removal by a cover tamper switch. Waterflow alarm vane switch shall be Model VSR-S manufactured by Potter Electric Signal Company.

Additional Information for Engineers:

Installation Tips

Tech Tips

Additional Information

If there is a shut off valve in line with the VSR-S it should be monitored. Closing this valve can prevent an alarm.

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