Potter Flow Switch – 1in Screw Connection – 25-50NB


SKU: VSRF-025/040 Category:


Flow switches are a critical part of any fire sprinkler system, and widely used throughout both commercial, residential and even domestic systems. Like pressure switches, they operate on a fairly basic principle – they open or close an electrical circuit when they are able to detect water moving through a pipe, as low as 15 litres per minute – and therefore they are extremely robust and reliable.

We offer Potter VSR vane-type switches from stock, available for all pipe sizes from 1”/25mm up to 8”/200mm. They are approved by LPCB, FM, UL, and they are CE-marked. To prevent false alarms due to small water movements, there is an adjustable retard of up to 30 seconds.

We use Potter VSR flow switches on all of our own assemblies – Zone Guardian remote flow switch test assembly, commercial flow test units, and residential/domestic valve sets.

Key features

  • Adjustable retard to eliminate false alarms
  • Threaded or U-bolt connection (see below)
  • Twin contacts (both NO and NC) for ultimate flexibility
  • IP54/NEMA-4 rated enclosure
  • All-metal external parts

Size ranges

  • Available from stock, we have the following:

VSR-S (EU) – threaded connection for fitting into tees for pipe size 1”/25mm to 2”/50mm, and usually used in residential and domestic systems

VSR-EU – U-bolt connection from 2”/50mm up to 8”/200mm, and generally used in commercial systems

  • If you need something different contact us, as we can source anything that’s available

We may also source other manufacturers and types of flow switches, although we may not always recommend them, so please do contact us if you don’t find what you need here. 

For more information, please refer to our full DATA SHEET