Flow Switch

Q: Does this measure flow?

No — it is a switch, not a meter. It closes a contact once flow rises past its trip point and opens again when flow falls below it.

Q: What flow does it trip at?

1.0 GPM, about 3.8 LPM, on both the M210 and the M310. Both are factory calibrated.

Q: What is the difference between the M210 and the M310?

The M310 takes higher line pressure (100 psi against 60 psi), can be supplied with a 25 A rating, and will switch a motor directly. See the table above.

Q: Is there a pre-wired option?

Both models can be supplied with an optional pre-wired 110 V receptacle box and power cord; on the M210 that option is limited to 15 A or 1800 W total.

Q: Which way must it be mounted?

Horizontally, and in filtered liquid only. Both models require this to work correctly.

Q: Can it switch a pump directly?

The M310 will switch motors up to 1 HP at 125 VAC or 2 HP at 250 VAC. For anything larger, use it to switch a contactor instead.

Q: How do I get a price?

Prices for the stocked 25 mm and 50 mm options are listed above — contact us for the tee-body versions or the 25 A option.

Flow switches that shut down pumps, heaters, UV units or ozone generators when water flow stops.

Price range: $160.00 through $180.00 ex GST

Option

Clear

Categories: Flowmeters, Plumbing Fittings

Applications: LSS, Public Aquarium, RAS, Water & Wastewater Treatment

Product Information

Key Features

A flow switch, not a flow meter — it gives a single on/off contact once flow rises past its trip point, so it protects equipment that must not run dry
Trip point is 1.0 GPM (about 3.8 LPM) and above on both the M210 and the M310, factory calibrated
Stocked in 25 mm (1″) and 50 mm (2″) pipe sizes, wired or unwired
M210 rated to 60 psi (about 414 kPa) at 10 A; M310 rated to 100 psi (about 690 kPa) at 10 A, or 25 A as an option
The M310 will switch a motor directly — up to 1 HP at 125 VAC or 2 HP at 250 VAC
Non-metallic wetted surfaces resist calcification; both models run to 110 °F (43 °C) continuous
Typical duty: interlocking pumps, heaters, UV units and ozone generators so they cannot run without flow
Sizing: choose on your pipe size first, then confirm your minimum normal flow sits comfortably above the 1.0 GPM (3.8 LPM) trip point. Pick the M310 if you need the higher 100 psi pressure rating or want to switch a motor directly. Both models must be mounted horizontally and used in filtered liquid only.

Specifications

Specification	M210	M310
Function	Flow switch — on/off contact, not a flow measurement	Flow switch — on/off contact, not a flow measurement
Trip point (rising flow)	1.0 GPM (about 3.8 LPM) and above	1.0 GPM (about 3.8 LPM) and above
Pipe connection	1″ PVC slip fitting	Contact us
Electrical connection	1/2″ electrical conduit	Contact us
Electrical rating	10 A	10 A, or 25 A optional
Direct motor switching	Contact us	Up to 1 HP at 125 VAC, 2 HP at 250 VAC
Max line pressure	60 psi (about 414 kPa)	100 psi (about 690 kPa)
Max continuous temperature	110 °F (43 °C)	110 °F (43 °C)
Wetted materials	PVC, polypropylene, Buna-N, stainless steel	PVC, polypropylene, Buna-N, EP
Optional pre-wired box	110 V receptacle box and power cord, max 15 A or 1800 W total	110 V receptacle box and power cord
Mounting	Horizontal only, filtered liquids only	Horizontal only, filtered liquids only
Pipe sizes stocked	25 mm (1″) and 50 mm (2″), wired or unwired	25 mm (1″) and 50 mm (2″), wired or unwired

Downloads

M210 Spec Sheet M310 Spec Sheet

Frequently Asked Questions

Does this measure flow?

What flow does it trip at?

What is the difference between the M210 and the M310?

Is there a pre-wired option?

Which way must it be mounted?

Can it switch a pump directly?

How do I get a price?

Spare Parts & Consumables

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Flow Switch

Product Information

Key Features

Specifications

Downloads

Frequently Asked Questions

Spare Parts & Consumables

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