Madison M4190-HP SPST Tank Liquid Level Switch 240VAC 900 psi
A selectable-function liquid level switch for tank side-mounting with a 1-inch NPT connection, rated to 900 psi and 240 VAC
- Product typeLight Switch
- Selectable switch function adapts to tank logic
- 900 psi rating handles high-pressure vessels
- 316 stainless float resists corrosion in harsh fluids
- 240 VAC 1 A SPDT contact controls pumps directly
- 302 °F max temperature suits hot liquid service
Liquid level switch for 900 psi tanks
The Madison M4190-HP is a side-mount SPST switch with selectable function for tank liquid level monitoring. It fits a 1 in NPT connection and uses a 316 stainless steel float on a 304 stainless steel stem. The assembly handles up to 240 VAC and 1 A with a 100 VA rating. Buyers needing a different mount style or lower pressure rating should look elsewhere.
Sustained load behaviour at 302 °F
The switch maintains its electrical ratings at the full 302 °F operating temperature limit. The 304 stainless steel stem and 316 stainless steel float resist corrosion during continuous immersion. The 100 VA rating and 1 A maximum current hold steady without derating across the temperature range. Installations exceeding 900 psi or requiring a different contact form will need another device.
Replaces fixed-function level switches
The selectable switch function lets one part replace separate normally-open or normally-closed units in existing 1 in NPT ports. The 3.98 in overall length matches many legacy side-mount cutouts. Upgrading is worthwhile when consolidation reduces spare-part counts or when the 900 psi rating exceeds the original equipment specification. Systems needing SPDT contacts or a different conduit size cannot use this model.
How it compares
Measured against everything we stock in Electrical Switches & Dimmers, at today’s prices. Recalculated every night.
- Price $198.99
- Pricier than about 86% of the 791 comparable items (median $39.99).
Specifications
| Product | |
|---|---|
| Brand name | Madison |
| Product type | Light Switch |
Questions about this item
How much heat does the 302 °F maximum operating temperature generate for the SPST switch during continuous use?
The switch is rated for up to 302 °F ambient temperature; it does not produce significant self-heating beyond the process temperature it senses.
What tank fitting does the 1 in NPT connection require on my vessel?
The side-mount switch threads into a standard 1 in NPT tank opening; no additional flange or adapter is needed.
Will the 316 stainless-steel float resist corrosion in the same fluids as my existing 304 stainless-steel fittings?
The 316 float offers higher corrosion resistance than 304 stem material, so it will perform at least as well in compatible media.
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