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📞 1300 987 789 |


KELCO Flow Switch - DN25 (1") Scr BSP Male / Female Brass Body (UB25-B-D)

The UB series inline flow switches are magnetically actuated piston style sensors that switch in response to very low fluid flows. They are ideal for all types of pressure boosting pump control and for the control of commercial or domestic hot and cold water systems.

They find application in monitoring industrial safety showers and in many applications where extreme reliability is paramount. The UB series flow switches are also ideal for constant pressure pump control.

  • Australian made.
  • Suits 20NB (3/4”) or 25NB (1”) Pipework.
  • Versatile all position Mounting.
  • 200BAR 2900 PSI Pressure Rating.
  • Switches at very low flows.
  • IP67 Weatherproof housing.
  • Solid machined brass body.
  • High flow through rating.
  • Handles liquids up to 90 degrees celsius.
  • Dimensions (mm): 127 L x 50 W x 93,5 H


  • The body of the UB25 flow switch is machined from solid Stainless Steel.
  • The piston is glass reinforced Polypropylene for water applications or Nylon for oil applications.
  • The piston return mechanism and the electrical switching action within the switch are achieved using high power magnets operating through the solid body of the switch.
  • The electrical housing is hose-proof & weatherproof, and is supplied with a 20mm cable gland, for conduit or cable entry.
  • The switch has 25mm 1” BSPT male Inlet and 1” BSPT female outlet.
  • Three electrical modules are available to suit the UB25 flow switch.


  • Hot and cold water pressure boosting.
  • Gravity hot water system control.
  • Hot water circulation actuation.
  • Safety shower alarm sentinel.
  • Wash down pump control.
  • Solar hot water control.
  • Mains water pressure boosting.

Operating Principle:

The Metal body of the UB25 flow switch houses a free sliding piston.

Any flow, either pulsed or continuous, causes the piston to be pushed back within the switch body to a point where liquid can pass around it and out of the switch.

When pushed back by flow, the piston actuates a magnetically linked switch.

When flow stops, the piston is pushed back to the off position by magnetic repulsion.

There are no springs in the wet area of the switch, and the magnetically isolated piston provides an exceptionally reliable mechanism.

The UB25 flow switches can be mounted in any orientation including upside down, in either horizontal or vertical pipework.

Contact PETRO industrial's team of bulk fuel storage and dispensing specialists for more information today!