The BL transmitter operates when connected to a bubble probe. The pressure variation in the pipe, depending on the liquid level, is converted into a standard electrical signal of 4-20 mA or 0-10 V (configurable). The equipment includes two contacts for two level control points. We have two standard models: – BL-1: 0-1000 mm H2O – BL-5: 0-5000 mm H2O- Power supply: 24 Vac/dc – Mounting: DIN guide.