Kelco C25 Inline Flow Switch

The Australian-made Kelco C25 is a compact 25mm inline flow switch designed to detect water flow through pump discharge pipework.

A magnetically actuated internal piston operates a normally open dry-contact switch when flow begins. The signal can be connected to a compatible pump-control panel, relay or programmable controller for flow monitoring and no-flow pump protection.

This Franklin-listed configuration is the C25-B-A-R-BSP with a brass body, 25mm male and female BSPT connections and a dry-contact reed-switch electrical module.

What the C25 does

• Detects whether water is flowing through the pipe
• Provides a normally open electrical signal when flow is detected
• Provides an external flow signal for compatible no-flow protection equipment
• Can help stop a pump following loss of flow when connected to the correct controller
• Can provide flow-status signalling to a relay, control panel or programmable logic controller
• Does not independently switch or protect a pump without compatible control equipment

Compatible pumps and applications

The C25 can be used with Franklin MH and EVR pumps and other clean-water pump systems where:

• The pipe connection is 25mm or 1-inch BSPT
• Maximum flow does not exceed 100 litres per minute
• A compatible flow-switch input, relay or control panel is installed
• The pump and pipework operate within the switch’s pressure and temperature limits

It can provide the external flow signal required by Franklin NFT no-flow protection when correctly connected to a compatible CP1 or CP3 full control panel.

Suitable applications include:

• Pump no-flow protection
• Pressure-boosting systems
• Flow confirmation
• Clean-water transfer systems
• Tank-filling systems
• Relay and programmable-controller signalling

Available model

• C25-B-A-R-BSP – Kelco C25 inline flow switch with 25mm male and female BSPT connections and dry-contact reed-switch output

No alternative C25 configuration is listed in the Franklin Electric Australia 2026 price list.

What is included

• One Kelco C25 inline flow switch
• Brass 25mm threaded flow-switch body
• Factory-fitted dry-contact electrical module
• Internal flow-sensing piston and retainer

Not included

• Franklin NFT protection relay
• CP1 or CP3 control panel
• Electrical cable or external relay
• Pump or motor
• Pipe unions, fittings or adaptors
• Check valve or inlet strainer
• Installation or electrical connection

Installation and selection warning

The C25-B dry-contact module is intended for control, relay, telemetry and programmable-controller signalling. It is rated to switch a maximum of 40 watts, 1 amp resistive and is not suitable for directly switching a pump motor or other inductive load.

The switch must be connected to a compatible relay, controller or control-panel input. All electrical connection must be completed by a licensed electrician.

Maximum recommended flow is 100 litres per minute. Do not use the C25 on larger Franklin pumps or pipework that can exceed this flow rate.

The male threaded end is the inlet and the switch must be installed in the correct flow direction. It can be mounted horizontally or vertically.

The C25 is designed for clean liquids. Iron, iron scale, sediment and foreign material can interfere with the magnetic piston. Install a suitable upstream strainer where contamination may be present.

Rapid flow reversal can damage the internal piston. A correctly selected non-return valve immediately upstream may be required. Pipe unions are also recommended so the switch can be removed for inspection and cleaning.

Confirm pipe size, flow rate, liquid type, operating temperature, system pressure and controller compatibility before ordering.