OS&Y Valve Supervisory Switch
An OS&Y valve tamper switch is an electric switch attached to the yoke of a rising stem valve that senses the valve position through an arm touching the stem. When the valve starts to close from fully open, the switch changes its contact and sends a warning to the fire panel.
It is used on OS&Y valves whose closure would disable the system, such as the sprinkler main control valve and fire pump suction and discharge valves. It can also be retrofitted to existing valves.
Main Applications
- Sprinkler main control OS&Y valves
- Fire pump suction and discharge valves
- Alarm station inlet valves
- Fire water tank outlet valves
Technical Data
| Function | Monitoring OS&Y valve position |
|---|---|
| Mounting | Clamped to the valve yoke |
| Sensing | Arm or roller touching the stem |
| Output | Dry contact (type by model) |
| Alarm moment | When valve leaves fully open |
| Protection class | By model |
| Cable entry | By model |
Material Options
| Part | Tamper switch |
|---|---|
| Housing | By model |
| Sensing arm | By model |
| Contact | By model |
| Mounting element | Yoke clamp |
Which material? As this product is not listed in the store, the contact type and yoke size are selected with you according to the valve size and the fire panel input type.
Advantages
Closed Valve Alert
- Reports as soon as closing starts
Retrofit
- Fits existing valves
Panel Integration
- Wired directly to the fire panel
Tamper Detection
- Unauthorised operation is noticed
Construction and Design Features
- Mounting clamp fitted to the yoke
- Arm sensing stem movement
- Contact block
- Cable gland
Send the OS&Y valve size and the fire panel input type; we will define the right tamper switch with you.
How to Choose?
- Set the valve sizeWrite the size so the switch fits the yoke.
- Choose the contactSelect the contact by the fire panel input type.
- Check the mountingMake sure the arm touches the stem correctly.
- Plan the testPartly close the valve and test the panel signal.
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