Faraday Switches Model QTFS3X and QTEZ3X-L capacitance operated touch activated electronic switches externally powered.

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Faraday Model QTFS3X -- EXTERNALLY POWERED
Also available with LED indicator light. Ask for model QTFS3X-L

QTFS3X Description Features Applications Specifications Typical Connections Prices Switches under Development

Model QTFS3X Description

QTFS3X.jpg (5658 bytes)

The module uses an electronic circuit to detect when an electrically conductive object comes in direct or near contact with the module's "cap" input. A human, touching a metal button or approaching a metal sensing plate connected to the cap input, increases the capacitance between the module and a nearby earth ground.

When the capacitance exceeds a specific level, the module circuit activates a transistor switch. Every 30 seconds the module automatically calibrates itself for maximum sensitivity. The typical capacitance sensitivity change is about 5 picofarads. A three position jumper sets the installed capacitance for 100pF, 200pF or 300pF of total capacitance.

The module has a "momentary" output, which will remain activated as long as the sensor input capacitance is higher than the calibrated level. The module’s output can sink up to 1 amp of current and handle voltages up to 30v.

Faraday Switches use true capacitance sensing methods. Unlike some “AC hum-type” touch activated switch circuits, Faraday Switches do not require the area around the switch to be rich in line-powered devices, such as fluorescent lamps. However, to insure reliable operations, an earth ground reference does need to be established. Each module provides a terminal for an earth ground connection. The QTFS3X model is an externally DC powered. The QTFS3X-L is identical but contains an indicator light. During standby operations the light glows dimly and glows brightly when the switch is activated.

The switch module is packaged in an epoxy sealed plastic box that is available with or without mounting feet. Standard barrier type screw terminals are provided to make all of the electrical connections. Dimensions are 1.0" x 1.0" x 0.75"

Faraday Switch Features