What is an OSY gate valve?
One type of valve commonly used to control water flow to fire sprinkler systems is known as an OS&Y gate valve. OS&Y means “outside stem and yoke” or “outside screw and yoke”. OS&Y gate valves operate by opening and closing via a gate, which lowers into or rises out of the valve.
What is a gate valve sensor?
The System Sensor OSY2 is used to monitor the open position of an Outside Screw and Yoke (OS&Y) type gate valve. The OSY2 consists of a rugged housing, intended for indoor and outdoor use.
What does NRS gate valve mean?
Non-Rising Stem
NRS means Non-Rising Stem. OS&Y means Outside Stem and Yoke. In an NRS valve, the stem will turn to open and close the gate, but the stem does not move up or down as it turns. With a OS&Y valve, as the stem turns, it moves into or out of the valve, which also moves the gate to open or seal the valve.
What is a supervisory device?
Conventional supervisory devices are devices that are used on an initiating device circuit and use a switch contact to short both sides of the device circuit together.
What is a supervisory fire alarm?
Supervisory – A supervisory condition means there is an issue with a system, process, or equipment that is monitored by the fire alarm control unit (see supervision section). An example of this would be a sprinkler system valve being closed, this would show up as a supervisory signal on the control unit.
Which way closes a gate valve?
clockwise
Gate valves close by turning the wheel clockwise until the water is off. Ball valves close by turning the straight handle a quarter turn clockwise until the water is off. To verify the water is off, turn on the hose bib next to the house valve.
What is tamper switch for fire protection?
A tamper switch is a mechanical and electrical device connected to a fire protection valve that signals a warning if the valve partially or fully closes. Regardless of the type of switch, they all function similarly. These devices feature an actuating unit, usually a lever or cable with a resting position.
What is the difference between NRS and OS&Y?
NRS means Non-Rising Stem. OS&Y means Outside Stem and Yoke. In an NRS gate valve, the stem turns to open and close the gate, but the stem does not move up or down as it turns. In an OS&Y valve, as the stem turns, it moves into or out of the valve, which also moves the gate to open or seal the valve.
