liquid level float switches

The AMETEK Float Switch family is made up of model series F8300, 610XXX and 8TJ143XXX. These devices open or close an electrical circuit at a predetermined level of liquid. They have been developed primarily for use in aircraft fuel and lubrication tanks but are equally suited for many industrial applications in remote and non-accessible locations where liquid level control is important.

Switches are designed for use with liquids under MIL-F-5572, MIL-F-5616, MIL-F5624, MIL-L-7808, and MIL-L-23699 throughout a temperature range of -65º to 275ºF, but may be used with most other liquids. 

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8TJ209 Capacitive Oil Level Sensor

The AMETEK 8TJ209 series of oil level sensors have been selected for business, regional and fighter applications since their introduction in 2000. The basic design can be easily adapted and qualified for new applications. Development cycle times are measured in weeks. Furthermore, to improve reliability of existing aircraft, AMETEK transmitters are readily adaptable to retrofit older engine lubrication systems.

The Capacitance Level Sensor produces a DC current signal proportional to fluid level when excited with 20 VAC at 30 KHz. Two concentric aluminum tubes along the length of the sensor form a variable capacitance circuit. The tube electrodes are isolated from each other using a molded RYTONTM insulator. The electrical capacitance of the tubes increases with the rising height of oil due to the higher dielectric constant of the oil compared to air. 
 

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