Boss Infinity Operator, Maintenance And Parts Manual page 14

DESCRIPTION OF COMPONENTS
CONTROL SYSTEM
The prime component of the compressor control system is the compressor inlet valve. The control
system is designed to match air supply to air demand and to prevent excessive discharge pressure
when compressor is at idle. Control of air delivery is accomplished by the inlet valve regulation
and modulation as directed by the discharge pressure regulator.
NORMALLY OPEN REGULATOR SOLENOID
A closed Furnas air pressure switch will energize the normally open regulator solenoid, thus closing
it. When the normally open regulator solenoid is closed, air pressure will rise. When it is open air
pressure falls only in the compressor sump.
NOTE: Most air tools operating pressure range is between 90 and 125 psi. Operating
above the tools recommended pressures will decrease the life of the tool. Higher
operating pressure can also over torque nuts and bolts fatiguing the fastener and mating
parts. Strictly adhere to tool operating pressures and torque standards set forth by the
tool manufacturer and the specifications of the equipment that work is being performed
on.
FURNAS SWITCH DESCRIPTION
The Furnas switch is a N.C. electrical switch set to open at 150 PSI and set to close at 115 PSI.
The Furnas switch controls the N.O. regulator solenoid. If service air pressure is under 150 PSI,
the Furnas switch will not trip keeping the N.O. inlet valve open and the compressor making air. If
the service valve is closed or the tool using the air is off, service line pressure will rise over 150
PSI. This will trip the Furnas switch to open. The regulator solenoid will open and send air
pressure to the inlet valve to close. With the inlet valve closed, the compressor will stop making
air. If the tool is turned on or the service valve is opened, the service line pressure will drop.
When the pressure falls to 115 PSI the Furnas switch will close energizing the N.O. regulator
solenoid closing off the air supply to the inlet valve. This will allow the inlet valve to open, and the
compressor will start making air to meet the demand.
INLET VALVE
The compressor inlet valve is a piston operated disc valve that regulates the inlet opening to control
capacity and serves as a check valve at shutdown.
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