The EFT7 Capacitance Level Indicator is intended for continuous measurement of non-conducting liquids such as fuel oil in tanks. The instrument is completely self-contained, requiring only a supply voltage and having a 4-20mA constant current and a 0-10 Volt signal output.
The EFT7 operates on the principle of a changing electric field caused by the presence or absence of liquid around the electrode. This change after amplification is used to provide the output signals.
An LED indicator shows that the unit is energised.
For tanks from 200mm to 3m the electrode is rigid and has an integral screen tube.