PPS - Plastic Paddle Flow Switch

The KOBOLD PPS Plastic Paddle Flow Switch is a bi-directional, paddle-type flow switch that monitors liquid flow in 1” to 3” pipes. A polysulfone paddle inserted into the line moves with flow in either direction, rotating an eccentric that lifts a magnet assembly to actuate a hermetically sealed reed switch. Switch status is visible through the transparent polysulfone housing. The paddle is trimmed to a marked length matched to the pipe diameter, so a single unit adapts across a range of line sizes. The PPS is offered with normally open, normally closed, or SPDT reed contacts, carries an IP65 rating, and is designed to handle media up to 225°F and 145 PSIG. It installs by simple insertion into a tee or coupling and is virtually maintenance-free in clean media.

Key Specifications

• Switching range: 9.5 to 28.5 GPM (rising flow, water, 1″–3″ pipe)
• Process connection: 1″ MNPT or G1 male threads
• Max. media temperature: 225°F
• Max. operating pressure: 145 PSIG
• Max. pressure drop: 1.45 PSI
• Repeatability: ±3%
• Protection: IP65 / NEMA 4

Materials and Construction

The PPS switch housing is transparent polysulfone, allowing the red magnet bearer to be seen as it moves so switch status can be confirmed at a glance. Internal wetted parts are stainless steel, PVDF, and a ceramic magnet. The reed switch is hermetically sealed and magnetically actuated, isolating the electrical contact from the media.

Contact Options and Electrical Connection

The PPS is available with normally open (N/O), normally closed (N/C), or SPDT changeover reed contacts. The N/C and N/O versions are rated to 230 VAC/DC, 2 A, 40 W / 40 VA; the SPDT version is rated to 100 VDC, 0.5 A, 5 W. Electrical connection is via a DIN 43 650 plug with cable gland. There is an option for ½″ NPT conduit fitting in place of the cable gland.

Installation

Installation is by insertion: the PPS threads into a standard tee fitting with NPT or G coupling. To promote a stable flow profile, allow a straight pipe run of at least three times the pipe diameter on each side of the tee. The paddle is trimmed to a marked length for the target pipe size and switch point.

The unit is designed for horizontal piping with the paddle mounted vertically. The broad face of the paddle should face against the flow, with the housing arrow pointing into the flow direction. Mounting on the top side of the pipe is recommended to reduce dirt deposits.

Applications

The PPS is designed to monitor the flow of low-viscosity liquids that are compatible with its wetted materials. Its reed-switch signal can trigger an alarm or indicator, and with a suitable relay it can be used to control pumps, motors, or valves. Typical liquid-monitoring uses may include pump and equipment flow protection, cooling- and process-water lines, and low-flow or no-flow alarming.

Because it responds to flow in either direction, the PPS is suited for applications where flow may run in either direction.

Made in the USA and BABA Compliance

The PPS Plastic Paddle Flow Switch is made in the USA, and BABA-compliant models are available for projects with domestic-content requirements.

Common Questions about PPS - Plastic Paddle Flow Switch