Madison Light Switch 1/8 in NPT Close On Rise 316 SS
Stainless-steel liquid-level switch closes on rise with 1/8 in NPT tank connection, 50 psi rating, 30 VA and 392 °F maximum
- Product typeLight Switch
- Close-on-rise actuation protects equipment from overflow
- 316 stainless steel construction resists corrosion in harsh fluids
- 50 psi pressure rating handles demanding tank environments
- 240 V, 0.28 A SPST contact suits high-voltage control circuits
- Compact 5.12 in overall length fits tight side-mount installations
1/8 in NPT Liquid Level Switch
This Madison switch monitors liquid levels in tanks and alternators using a stainless-steel float that actuates on rising fluid. The SPST contact closes when the level rises, completing a circuit for alarms or pump control. Rated for 30 VA at up to 240 V, it suits industrial and marine monitoring tasks. Buyers needing a normally-open fill control will find the close-on-rise action appropriate.
Side-mount installation with 1/8 in NPT threads
The switch threads directly into a 1/8 in NPT tank port, so no separate flange or bracket is required. The 316 stainless-steel stem and float resist corrosion in water, oil or coolant. Over-tightening can distort the threads and prevent the float from moving freely. Ensure the conduit entry is sealed to keep moisture out of the wiring compartment.
Verify tank port and electrical limits before
Confirm the tank has a 1/8 in NPT opening and that system pressure stays below 50 psi. The float needs 1.54 in diameter clearance inside the vessel to swing without hitting walls or baffles. Maximum operating temperature is 392 °F, and the contact must not exceed 0.28 A at 240 V. If your circuit demands higher current, a relay is required.
How it compares
Measured against everything we stock in Electrical Switches & Dimmers, at today’s prices. Recalculated every night.
- Price $82.99
- Pricier than about 71% of the 791 comparable items (median $39.99).
Specifications
| Product | |
|---|---|
| Brand name | Madison |
| Product type | Light Switch |
Questions about this item
How do I verify the switch closes its circuit when the liquid level rises in the tank?
Apply power within the 30 VA, 0.28 A, 240 V limits and observe the SPST contact close as the float lifts; the stainless steel float and stem move freely on the 1/8 in NPT side mount.
What comes with the switch and what must I supply separately?
The unit includes the 316 SS body, 1.54 in float, 2.74 in stem and 1/8 in NPT conduit fitting; you provide wiring, a 1/8 in NPT tank port and a power source rated for 50 psi max pressure.
Which version suits a 240 V, 30 VA control circuit in a 392 °F environment?
This SPST close-on-rise model with 316 SS construction, 50 psi rating and 5.12 in overall length meets those electrical and temperature limits.
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