Models T20 & T21 Single-stage And Dual-stage Float Switches
T20 and T21 units are user-friendly, reliable float switches designed for top mounting to tanks or vessels. T20 units utilise a single switch mechanism and float. T21 units utilise two switch mechanisms and two separate floats when widely spaced actuating levels are required. T20 and T21 models are available for any type of open or closed vessel with either threaded or flanged type mounting and actuating depths up to 1219 mm (48 inches).
Operating Principle
The buoyancy force of a process liquid on the float causes the float to move with the liquid surface. The movement of the float moves an attraction sleeve into the field of the switch magnet, pulling the magnet toward the sleeve and actuating the switch.
Applications
- Day tanks
- Fuel storage tanks
- Flash tanks
- Condensate Receivers
- Cooling towers
- Interface
- High and high/high alarm from single tank entry
Features
- Float diameters of 3″ × 5″, 4″ and 4 1⁄2″ available
- Tank connections available in 1″ NPT, cast iron, forged, or stainless steel flanges
- Maintenance free
- Choice of switch mechanism:
- Dry contact
- Hermetically sealed
- Pneumatic
- Choice of switch enclosure:
- NEMA 1 carbon steel for pneumatics
- TYPE 4X/7/9 Class I, Div. 1, Groups C & D, polymer coated aluminium
- TYPE 4X/7/9 Class I, Div. 1, Group B, polymer coated aluminium
Options
- NACE
- ATEX approved housing
- Housing heater
- Float guide cage
- Tropicalized switch mechanism
- Special flange face finishes
- Submersible housing
- Elevated temperature
