The Model WFSR-F is a pressure operated switch with an adjustable, instantly recycling pneumatic retard to prevent false alarms due to water pressure variation. The WFSR-F is connected into the alarm port of a wet sprinkler system alarm check valve.

Unique Features

Codes & Approvals

Engineering Specifications

Pressure Type Waterflow Switch with Retard: UL, CUL Listed / FM, VdS Approved and CE Marked pressure type waterflow switches shall be furnished and installed on the alarm port of each alarm check valve where indicated on the drawings and plans and as required by applicable local and national codes and standards. Pressure type waterflow switches shall consist of a non-corrosive ½” NPT male nipple for connection to the alarm port of the alarm check valve, a non-corrosive pressure chamber and diaphragm, field replaceable instantly recycling adjustable time delay mechanism to prevent false alarms from water surges and two SPDT switch contacts. The device shall be NEMA 4 rated and the enclosure shall be held captive by tamper resistant screws. It shall be possible to install an optional cover tamper switch to detect removal of the enclosure. The device shall be listed for pressures up to 175 psi and shall be factory set to operate at 5-8 psi. The activation point of the device shall not be adjustable. A minimum pressure of 5-8 psi is required to activate the retard timer. Any interruption in pressure shall reset the timer. Expiration of the retard time shall result in the operation of two sets of single pole double throw (SPDT) switch contacts rated at 15A, 125VAC and 2A, 30VDC. Pressure type waterflow switch shall be model WFSR-F manufactured by Potter Electric Signal Company LLC. All in-line valves shall be electrically supervised in the full open position.

Additional Engineering Information

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Additional Information

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