Alicat MC Series Mass Flow Controller User Manual
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MCV Controller Operating Notes
Alicat’s MCV mass flow controller is equipped with an integrated Swagelok®
positive shutoff valve.
The normally closed valve is air actuated and will remain closed until it is
connected to an air source supplying between 60 and 120 psig of air pressure.
Once the appropriate amount of air pressure is supplied to the shutoff valve,
it will open, allowing flow through the mass controller. Air pressure must be
removed from the shutoff valve in order for the valve to close.
A common method for actuating the shutoff valve incorporates a three-way
solenoid valve (below).
Air pressure is applied to one side of the solenoid valve while the other side of
the solenoid is left open to atmosphere.
When the solenoid is energized, air pressure is delivered to the shutoff valve,
allowing it to open.
When the solenoid is returned to a relaxed state, air pressure is removed from
the shutoff valve, allowing it to close. The air pressure is vented to atmosphere.
Solenoid valves for use with the MCV mass flow controller can be ordered from Alicat.
Note: All standard MC-Series device features and functions are available on the MCV-
Series and operate in accordance with the standard MC-Series operating instructions.
Three-way Solenoid Valve
MCV Controller
Vent
Air Supply
MCV controller and three-way solenoid valve.