Alarm systems are used for the detection of light liquids or of the maximum level of a liquid in separators. This allows for safe operation of separators for light liquids. One of the requirements specified in the standard EN 858-1 is that all separator systems in Europe must be equipped with a warning device. According to DIN 1999-100 5.7, an alarm system is not required in Germany if the possibility of light liquids escaping from the separator or its containment can be fully excluded.

The AFRISO WGA 01 alarm unit for oil and petrol separators, consisting of the control unit WGA 01 and the capacitance probe WGA-ES4, is used to monitor the thickness of interface layers. An optional PTC thermistor probe (WGA-R6) can also be connected to monitor the maximum level. WGA-ES4 is mounted at least 150 mm below the constant level of the separator. As soon as the oil or petrol layer reaches the critical level, the device generates an alarm signal.

If the probe WGA-R6 is additionally mounted above the constant level, an alarm is immediately triggered in the case of a malfunction, for example a clogged outlet and a resulting overfill condition of the separator so that light liquids escaping from the system or its containment are immediately detected, and appropriate countermeasures can be taken.

The control unit is contained in a robust wall mounting housing with test and Acknowledge buttons as well as two LEDs for normal condition and alarm condition. WGA 01 is supplied with AC 230 V and suitable for ambient temperatures of 0 °C to +40 °C. The control unit WGA 01 features visual and audible alarms as well as two relay outputs (voltage-free changeover contacts, cannot be acknowledged) for additional switching tasks.

The maximum distance between the control unit and the probes is 200 m. The warning device for oil and petrol separators WGA 01 is approved for operation in hazardous areas (EX) and can be used by, for example, waste management companies, car dealerships, repair shops, airports, petrol stations, car wash companies or scrapyards. The system is fast and easy to install and commission.