Johnson Ultima Automatic Bilge Pump Switch - MW
Johnson Ultima Automatic Bilge Pump Switch
The Johnson Ultima Switch uses the patented Mirus field effect detector cells, producing micro-electrical fields that detect disruptions caused by water and fluids. The detector cells are totally sealed and are never in contact with the water, will not corrode, and are not affected by oil for foreign debris. Johnson Ultima Switch activates at a 2" fluid level and deactivates at a 3/4" fluid level. An eight second delay prevents false starts.
The Ultima Switch is rated to handle bilge pumps up to 20A, at 12V or 24V.
- No moving parts
- Totally sealed solid state electronics and field detectors
- No mercury
- No exposed sensors eliminate corrosion possibilities
- Unique 3-way switch disables piezo alarm while keeping warning LED lit
- Environmentally sensitive
Click to Download Johnson Ultima Auto Switch Manual
Frequently Asked Questions
What does the Johnson Ultima Automatic Bilge Pump Switch do?
The Johnson Ultima Automatic Bilge Pump Switch is designed to automatically activate and deactivate a bilge pump based on fluid level. It uses patented field effect detector technology to sense water without relying on traditional moving float components.
At what fluid levels does the Johnson Ultima Switch turn on and off?
The Johnson Ultima Switch activates at a 2" fluid level and deactivates at a 3/4" fluid level. It also includes an 8-second delay to help prevent false starts.
What makes the Johnson Ultima Switch different from a traditional float switch?
This switch has no moving parts and uses sealed solid state electronics with field detectors instead of exposed sensors or a moving float. That design helps reduce corrosion concerns and improves reliability in marine environments.
What pump and voltage capacity is the Johnson Ultima Switch rated for?
The Johnson Ultima Switch is rated to handle bilge pumps up to 20 amps at either 12V or 24V.
Does this switch have any built-in alarm or indicator features?
Yes. It features a unique 3-way switch that disables the piezo alarm while keeping the warning LED lit.

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