Flow Meter LC Digital with electronic registration for refined fuels (with E-7 valve, optical air eliminator, and high-capacity air eliminator) Type M-15 The Liquid Controls Optical Air Eliminator is designed for use with LectroCount® Electronic Registers. It provides for the efficient elimination of air and vapor with virtually no moving parts and without the need for floats, guide rods, reed strips, and valve plates.Flow meter lc An optical sensor, installed in the wall of the air eliminator, is used to monitor the liquid level. The presence or absence of liquid at the sensor level activates or deactivates a solenoid located at the top of the air eliminator. The Optical Air Eliminator requires the use of a solenoid operated valve such as the E-7 or A2848-11 supplied by Liquid Controls. The solenoid operated, air-release valve, located at the top of the air eliminator, is either open or closed. When the liquid level is below the optical sensor, the solenoid opens and vents air and vapor to atmospheric pressure. Simultaneously, the electronic control valve (E-7 or A2848-11) at the meter outlet closes.