‘Intelligent’ capacitance sensor for fuel level measurement

LEAMINGTON Spa-based Fozmula Ltd, manufacturers of fuel sensors and switches, have launched the advanced T/LL140 ‘intelligent’ capacitance sensor, designed to meet the demand for a more flexible and efficient method of measuring fuel levels where both the types and qualities of fuel and fuel tank configurations make conventional measuring devices awkward or difficult to use.

The device has no moving parts because liquid depth is measured by changes in capacitance, governed by the unit’s inbuilt intelligence, which allows it to self-calibrate in situ and to function equally effectively with biodiesel or red diesel fuel alternatives, or with fuel additives. It is also well suited for telemetry applications which remotely monitor the contents of the fuel tank, calculating fuel usage and detecting any sudden loss.

Moreover, the sensor can output its signal in resistance, voltage or PWM mode, to suit the engine-management system. Another primary feature of the T/LL140 is its sensor stem, which can be cut to size by the user to suit individual tank requirements. The device also includes the option to use fuel feed and return pipes. These can be fitted with customer-specified tube diameters and fixed or swivel-type tube fittings.

Designed and manufactured to a high specification, the T/LL140 offers ease of maintenance and can be deployed in a variety of demanding operating environments, including off-road and rough-terrain vehicles and boats, industrial machinery, compressors, generating sets, awkwardly situated static fuel tanks and mobile lighting towers.

Key features of the T/LL140 include:

• No moving parts, making it suitable for use in applications where there is high-level vibration, fluid turbulence or a likelihood of contaminating solids.
• Has the intelligence to self-recalibrate automatically for different fluid types (oil, diesel, biodiesel etc) and for different tank shapes including round, saddle-shaped and cylindrical.
• Electronics allow an alarm switch to be set at any point along the sensor stem to operate a warning light or alarm, to operate a pump or to send a signal.
• Sensor stem can be cut to any desired length by the user with no detrimental effects on performance.
• Complies with IP67 sealing requirements and functions in low- and high-temperature (–20ºC to +85ºC) environments. Vibration and EMC tested to international standards.
• Can be adapted for special projects, including fuel feed and return pipes and special connections (eg flying leads, customer-specified connectors etc). A five-hole SAE flange fitment configuration is provided as standard.