Internal Liquid Level Switch
Model KC

The Model KC & KCF is a versatile internal service, top mounted liquid level switch. With its many optional features, the KC and KCF can be used for a wide variety of applications. Its simple mounting makes it adaptable to many installations.


Float: The float will vary in shape and diameter depending on the specific gravity of the liquid, and the immersion length. The standard float material is 300 series Stainless Steel.
Trim: The float rod and its related hardware are standard in 300 series Stainless Steel. The enclosing tube is 316 Stainless Steel.
Mounting: The standard connection is 1" NPT, mounting on the tank or vessel top. When installing, the float must be removed, the control inserted into the vessel and the float re-attached. Flange mounting is an optional feature. A suitable flange will allow installation of the control without removal and reassembly of the float.
Immersion Length: The standard immersion is 12" as measured from the bottom of the mounting threads or face of the flange, if applicable, to the bottom of the float. The control can be set to a specific high or low level point. These points are also measured from the bottom of the mounting threads and must be specified in the RFQ.
Differential: With a single switch, the standard differential is approximately 5/8". Wide differential options are available. Field adjustment of the actuating points can be made by raising or lowering the switch on the enclosing tube.
Switch Housing: A water-tight/dust-tight or hazardous rated housing is available. Hazardous housing is rated to:

  • Class I, Groups B,C,D
  • Class II, Groups E,F,G
  • Class III
  • Class I, Zone 1, AEx d IIC
  • Ex d IIC
  • Type 4X
  • IP 66
  • 4X, 7BCD, 9EFG

and listed as:

  • FM Standard 3615
  • UL Standard 1203
  • CSA Standard C22.2 No. 30
  • NEMA Compliance
  • UL 60079-0/UL 60079-1
  • CSA 60079-0/CSA 60079-1
  • ATEX Directive 94/9/EC
  • UL 50
  • IEC 60529

Conduit Connection: 3/4" NPT is standard, 1/2" NPT or M20 are available.
Switches: See Model OF or Z.

Optional Features:

Cooling Fins: For application with a process temperature above 400°F, cooling fins are used to dissipate as much as 200°F which would otherwise be transmitted to the switches.

Wide Differential: For applications with a differential greater than provided by the standard model, the following options are available:

  1. Two Switch: With two switches up to 4 1/2" of differential can be obtained.
  2. Sliding Piston: With this design, the piston travels along the rod, making contact with high and low-level stops. The magnet is strong enough to hold the piston in place while the liquid level raises and lowers the rod. The maximum differential with this design is three inches.
  3. Sliding Float: With this design, the float travels along the rod, making contact with high and low-level stops. This design is used for differentials larger than 4".


Starting in the unactuated position, a rising liquid level will lift the float and rod, raising the actuating piston towards the magnetic operating zone of the switch assembly. A permanent magnet, located within the switch assembly, snaps forward from the magnetic attraction. In doing so, a plunger is depressed, actuating a micro switch. When the level decreases, the float falls away, pulling the actuating piston to its original position, releasing the permanent magnet, re-setting the switch assembly to its unactuated position.