Water Flow Indicator with Retard PN25
- Water flow Indicator with Retard PN25 An alarm indicating water flow in a building’s fire protection system such as an activated fire sprinkler head.
Product Description
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Product Detail
Water flow Indicator with Retard PN25 is a vane-type waterflow switch designed to detect a sustained flow of water exceeding 10 GPM. It is intended for use on wet-pipe sprinkler systems only. The Model VSR has a built-in adjustable pneumatic retard device delays actuation of the electrical switches to reduce the possibility of false alarms caused by one or more transient flow surges. The Model VSR-S does not have a retard to prevent false alarm, therefore, it should NOT be used on systems with variable water pressure, except in the case of elevator recall. The unit includes two single-pole double-throw snap action switches used to operate local alarms, indicate signals to annunciator panels, trip municipal fire alarm boxes, start fire pumps, or any other function that can be initiated or controlled by the opening or closing of an electrical switch. The device may be installed on the main riser to give a system waterflow signal or on branch feed mains, cross mains, or branch lines to give a waterflow signal by zone or area.
INSTALLATION VSR-S Model These devices may be mounted in horizontal or vertical pipe. On horizontal pipe they should be installed on the top side of the pipe where they will be accessible. The units should not be installed within 6” (15 cm) of a valve, drain or fitting that changes the direction of the waterflow. Select the proper paddle for the pipe size and type of TEE used; see Figure 1 for instructions on changing paddle. The unit has a 1” NPT bushing for threading into a non-corrosive TEE. See Figure 2 for proper TEE size, type and installation. Use no more than three wraps of Teflon tape. Screw the device into the TEE fitting as shown in Figure 2. Care must be taken to properly orient the device for the direction of water- flow. The vane must not rub the inside of the TEE or bind in any way. The stem should move freely when operated by hand. The device can also be used in copper or plastic pipe installations with the proper adapters so that the specified TEE fitting may be installed on
