SSI Technologies - Application Note FT-AN1
Fluid-trac® Two Wire ( Resistive Emulation ) - 30768 Fluid-Trac® 2-Wire Level Sensor(Resistive Emulation)
Product Description
The Fluid-Trac® 2-wire level
sensor is a non-contact liquid level
sensor that can be used as a more reliable and accurate replacement for standard 30-240 ohm resistive float sender, reed-switch tube
sensors or capacitive tube senders. The FluidTrac® 2-wire level
sensor is commonly used to work with fuel gauges in the automotive, marine and construction industries.
Measurement Technology
The traditional resistive float sender uses a potentiometer attached to a float at the end of an actuating arm to provide a level indication. This technology interfaces with the instrument cluster’s fuel gauge which is typically a coil driven needle gauge. As the resistive float sender’s resistance changes with level, the current through the coil in the gauge changes causing a deflection of the needle. This approach has been used for many years. Fluid-Trac® uses ultrasonic technology to generate a high frequency sound wave and measure the time for the echo to reflect off of the liquid’s surface and return. The distance from the level
sensor to the liquid is calculated based on the speed of sound. The measured distance is converted into a voltage that drives the gauge based on a strapping table contained in the level
sensor. Easier to install or Service: Fluid-Trac® has no components to protrude into the fluid that need to be bent for removal. Better Design: With a minimum clearance required, access panels or Pye Plates can be eliminated.
Product Features
Digital Filtering: Digital filtering eliminates errors due to liquids sloshing in mobile tanks. More Accurate: Distance accuracy of +/- 0.125 inches (1/8
th inch) Tank Profiling: Factory programmable strapping tables for unique tank shapes. More reliable: Fluid-Trac® is non-contacting. Resistive float senders have a wiper that slides across a resistive strip that with time can wear out and cause intermittent or complete loss of the signal Chemical compatibility: Fluid-Trac® works with a wide variety of media including gasoline, diesel fuel, urea (ADBLUE),oils, hydraulic fluid and black/gray water. Non-Invasive: Fluid-Trac® mounts to the same opening as the resistive float sender but does not protrude into the tank.
SSI TECHNOLOGIES, INC. Controls Division 2643 West Court St. Janesville, WI 53548-5011 Phone: (608)758-1500 Fax: (608)758-2491 Copyright May 24, 2007 SSI Technologies Inc. All Rights Reserved SSI Technologies, Inc. Revision 2 1
