The Potter Electric Signal VSR-3.5 is a vane-type waterflow alarm switch for 3-1/2″ wet sprinkler pipe. First, it clamps to the top of horizontal pipe or to vertical pipe with a saddle U-bolt. Then, flow downstream pivots the vane and trips two SPDT switches.
How the Potter Electric Signal VSR-3.5 works
A minimum flow of 10 GPM (38 LPM) activates the device. In addition, an adjustable 0-90 second pneumatic retard helps prevent false alarms from pressure surges. As a result, the switch signals only sustained flow, not transient bumps. Specifically, it is UL Listed for schedule 10 through 40 steel pipe at 3-1/2″ nominal size.
VSR-3.5 specifications
- Pipe size: 3-1/2″ nominal, schedules 10-40 (UL)
- Nominal pipe O.D.: 4.000″ (101.6 mm)
- Contacts: two SPDT (Form C), 10A at 125/250VAC; 2A at 30VDC resistive
- Activation flow: 10 GPM (38 LPM) minimum
- Retard: 0-90 second adjustable, instantly recycling
- Service pressure: 450 PSI (31 BAR) – UL
- Maximum surge: 18 FPS (5.5 m/s)
- Operating temperature: 40°F to 120°F (4.5°C to 49°C) – UL
- Enclosure: composite cover, die-cast aluminum base, NEMA 4 / IP54
- Conduit: two 1/2″ knockouts; separate switch compartments for dissimilar voltages
- Listings: UL Listed; service per NFPA 13, 13D, 13R, and NFPA 72
- Potter part number: 1144435
Field service notes
However, do not trim the paddle — it voids the warranty and prevents activation. Also, the retard/switch assembly (stock 1029030) is field-replaceable without draining the system. Finally, Potter rates normal service life at 10-15 years.
For more information, contact the Life Safety Consultants team at (888) 557-0558, or email us at: sales@lifesafetycom.com
Additional information
| Weight | 8.12 lbs |
|---|---|
| Dimensions | 3 × 5.6 × 5.3 in |
| Condition | New |
| Manufacturers | Potter |
| Part Type | Replacement Part |
