The Equalizer uses the principle of removing the heat from the system, which is required to lower the temperature of the liquid ammonia to its related pressure as it moves through the system, in effect, isolating the system into two separate systems. The two systems can be considered the supply system and the metering system.
The present system of applying ammonia can be considered a series of orifices (or points of resistance) with the meter having the ability to compensate for pressure variations both upstream and downstream, but the meter has no ability to read or compensate for any vapor in the system.
The ability of the Equalizer to remove vapor from the system just prior to the meter provides a consistent system from the inlet of the meter on into the ground under most all desired operation conditions, provided the system can support it.
The principle of meters in use today controls a pressure difference across an adjustable orifice (meter barrel) independent of the pressure, either upstream or downstream. As the meter setting is reduced for a given set of conditions, there is an increase in the ability to control the system.
