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Outdoor Tank Alarm (High Water Alarm) - 15 foot Mercury Float

SKU: SP-4100

Price: $94.99

Weight: 3.00 lb
Stock Quantity: Made to Order

Delivery: Ships in 5-7 Business Days

The SP-4100 alarm system is designed to monitor liquid levels in sump basins, holding tanks, lift stations tanks and many other non-potable water and wastewater applications. Comes individually boxed with Cable tie and Instruction sheet.

This alarm comes in a Type 4X non-metallic enclosure with external mounting feet and a gasketed door for outdoor use. It has a large red illuminating beacon, piezo, with Test and Silence toggle switch.

The SP-4100 is design to sound an audible piezo horn and illuminate the red beacon light to notify of an alarm situation. There is a silence switch to turn the piezo horn off while fixing the alarm (the red alarm light will remain on until the alarm conditions are remedied).


  • Alarm test and horn silence toggle with auto reset
  • Complete alarm includes a (Mercury) float switch with mounting strap and 15 foot cord.
  • Alarm operates on 12 Volts, reducing the possibility of accidental electric shock.
  • CG2OY500 Float Switch

PDF Spec Sheet


  • Voltage:
    • Primary: 120 VAC, 60 Hz
    • Secondary: 12 VAC 60 Hz
  • Enclosure Type 4X non-metalic enclosure rated for indoor or outdoor use 8" X 4 1/2" X 4 1/4" (NEMA 3R)
  • Alarm horn 85 Decibels at 10 feet
  • Power Cord 6 feet 120 VAC (NEMA 5-15P)
  • Features:
    • Red "Alarm On" Beacon
    • Alarm test and horn silence button with auto reset
  • Low voltage screw terminals Class 2 Output, 12 VAC, connect ONLY the float switch leads to the Low voltage screw terminals.

Float Switch - CG2OY1500 (Included)

  • Cable: 15 foot length, 18 Ga. 2 conductor, SJOW chlorinated polyethylene jacket
  • Float: 2.63" Dia X 3.58" long ABS outer shell
  • Switch: 10 Deg operating angle, hermetically sealed mercury switch

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