Type RAX: Paddle flow switches, reed switch contact, built-in 16A SPDT relay

1: Cleavable paddle                  2: Plastic body and plastic 3/4″ BSPP union nut

3: Connection box                    4: Adjustment screw

5: Pilot light

Main uses

General application in flow detection.  Recommended mounting position is on horizontal pipes, but can be mounted in any position.  For water flow detection on dia 15 to 100mm water pipes. The built-in relay with SPDT contact can be used on resistive loads up to 15A 250V. The pilot light shows the contact position.


Functional principle

Balanced magnetic paddle mounted perpendicular to the flow and activating a reed switch through the wall. The return of the paddle is by made by magnetic action, without spring. No seal or liquid can pass between the piping system and the electrical contact. Suitable for corrosive water pools and spas and salination chlorination and bromination systems. Must not be used for water containing magnetic particles or high viscosity liquids, which block the movement of the paddle.


By cleaving the paddle

 Fine adjustment by screw driver on internal dial (on models with connection box only)

Paddle shaft: Titanium, providing an outstanding corrosion resistance, and improved mechanical live. Suitable for corrosive water pools and spas and salination, chlorination and bromination systems.

Main housing material: PPO, fiber glass reinforced for improved pressure resistance, usable with potable water.

Paddle: PPO, 12 mm width, can be cleaved into 4 sections numbered 1 to 4  for pipe diameter adjustment.

Pipe mounting:  Fiber glass reinforced union nut, ¾ BSPP, mounting on ¾ BSPP male fitting with gasket. Recommended torque:  7±1Nm.

Gasket: NBR

Electrical rating: 15A, 250V, resistive load. Use on inductive circuits reduces electrical rating.

Electric contact type: SPDT

Liquid compatibility: For use with clean water and liquids without magnetic particles and without chemical incompatibility with PPO and titanium.

Nominal pressure at 20°C: 1MPa (PN10)


Liquid temperature ranges: 5 to 100°C (cannot be used in water freezing pipes).

Ambient temperature range: 5 to 80°C

Ingress protection: IP65

Calibration tolerances: +/-15% (on paddle operating force at end of paddle 1).

Electrical connection:  2.5mm² connection block with screw terminals M16 cable gland output.

Installation instructions:

– Check carefully the paddle orientation: The arrow on housing must be exactly parallel to the pipe.

– A 5 mm minimum gap must be respected between end of the paddle and tube wall opposite to the fitting.

– We recommend the use of nozzles of length below or equal to 18mm between the gasket seat and the inside of the tube and with  an inner diameter above or equal to 13.5 mm, to avoid blocking of the paddle.

Accessories: 3/4″ male PVC saddles for DN40 to DN100 (OD) PVC pipes, and other fittings: see last section of this catalogue.

Options (MOQ apply): nickel plated ¾” BSPP union nut.

Important notice: In the case of plastic pipes (PVC, PE), the DN (nominal diameter) corresponds to the outside diameter and wall thickness is variable depending on the application. This must be taken into account to avoid blocking the paddle. In the case of metal pipes, the inner diameter corresponds to the DN. Flow values ​​data are for tubes whose internal diameter corresponds to DN.



Main references (With type A cleavable paddle)

Calibration (Calibration force ±15%, measured at end of paddle N°1)

Low span end: 3gr

Middle span:7gr

High span end:14 gr

RAX636680G35N00C RAX676680G35N00C




2D&3D Drawing