Fixed-Setpoint Flow Switches
Since they come factory set to a specific set point, these switches are easier to install than adjustable flow switches. As flowing liquid pushes an internal piston, the switch reads the position of the piston to measure the flow. When the piston passes the set point, the switch actuates. They’re accurate in any mounting orientation.
These switches are calibrated with and measure water accurately. They can also be used with other liquids by applying your liquid’s specific-gravity conversion factor to calculate the new set point.
Choose a fitting material that is compatible with the liquid you intend to run through your line. Polypropylene and PPS plastic fittings work with a wide range of chemicals. However, they can crack from impact or when overtightened. Bronze and 316 stainless steel fittings resist impact better than plastic fittings.
SPDT (single pole, double throw) switches can either turn one device from off to on (normally open) or from on to off (normally closed).
For technical drawings and 3-D models, click on a part number.

Stainless Steel Body
with Female Fittings
Conduit | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pipe Size | Thread Type | Gender | Set Point, gpm | Approx. Difference Between Setpoint and Reset Point, gpm | Max. Pressure | Temp. Range, °F | Max. Switching Current @ Voltage | Trade Size | Thread Type | Gender | End-to-End Lg. | Mounting Orientation | Each | |
Bronze Body with Bronze Fittings | ||||||||||||||
SPDT | ||||||||||||||
1 | NPT | Female | 0.5 | 0.075 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 0000000 |
1 | NPT | Female | 2 | 0.3 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 | NPT | Female | 4 | 0.6 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 | NPT | Female | 6 | 0.9 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 | NPT | Female | 8 | 1.2 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 1/4 | NPT | Female | 1 | 0.15 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4" | Any | 00000000 | 000000 |
1 1/4 | NPT | Female | 4 | 0.6 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4" | Any | 00000000 | 000000 |
1 1/4 | NPT | Female | 20 | 3 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4" | Any | 00000000 | 000000 |
1 1/2 | NPT | Female | 1.5 | 0.225 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4 1/2" | Any | 00000000 | 000000 |
1 1/2 | NPT | Female | 5 | 0.75 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4 1/2" | Any | 00000000 | 000000 |
1 1/2 | NPT | Female | 30 | 4.5 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4 1/2" | Any | 00000000 | 000000 |
2 | NPT | Female | 2 | 0.3 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 5 3/8" | Any | 00000000 | 000000 |
2 | NPT | Female | 5 | 0.75 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 5 3/8" | Any | 00000000 | 000000 |
2 | NPT | Female | 50 | 7.5 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 5 3/8" | Any | 00000000 | 000000 |
316 Stainless Steel Body with 316 Stainless Steel Fittings | ||||||||||||||
SPDT | ||||||||||||||
1 | NPT | Female | 0.5 | 0.075 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 | NPT | Female | 2 | 0.3 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 | NPT | Female | 4 | 0.6 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 | NPT | Female | 6 | 0.9 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 | NPT | Female | 8 | 1.2 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 3 1/4" | Any | 00000000 | 000000 |
1 1/4 | NPT | Female | 1 | 0.15 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4 1/2" | Any | 00000000 | 00000000 |
1 1/4 | NPT | Female | 4 | 0.6 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 4 1/2" | Any | 00000000 | 00000000 |
2 | NPT | Female | 2 | 0.3 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 5 3/8" | Any | 00000000 | 00000000 |
2 | NPT | Female | 5 | 0.75 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 5 3/8" | Any | 00000000 | 00000000 |
2 | NPT | Female | 50 | 7.5 | 400 psi @ 70 ° F | -20° to 300° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | 1/2 | NPT | Male | 5 3/8" | Any | 00000000 | 00000000 |

Pipe Size | Thread Type | Gender | Set Point, gpm | Approx. Difference Between Setpoint and Reset Point, gpm | Max. Pressure | Temp. Range, °F | Max. Switching Current @ Voltage | Mounting Orientation | Each | ||
PPS Plastic Body with PPS Plastic Fittings | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
SPDT | |||||||||||
A | 1/4 | NPT | Female | 0.1 | 0.02 | 250 psi @ 70 ° F | 0° to 225° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | Any | 00000000 | 0000000 |
A | 1/4 | NPT | Female | 0.25 | 0.05 | 250 psi @ 70 ° F | 0° to 225° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | Any | 00000000 | 000000 |
A | 1/4 | NPT | Female | 1 | 0.2 | 250 psi @ 70 ° F | 0° to 225° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | Any | 00000000 | 000000 |
A | 1/4 | NPT | Female | 1.5 | 0.3 | 250 psi @ 70 ° F | 0° to 225° | 400 mA @ 30 V AC 170 mA @ 120 V AC 80 mA @ 240 V AC 300 mA @ 30 V DC 130 mA @ 120 V DC 60 mA @ 240 V DC | Any | 00000000 | 000000 |