Vmac G300003, Installation, Owners And Service Manual

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VMAC
– Vehicle Mounted Air Compressors
VMAC Technical Support: 1-888-241-2289
VMAC Knowledge Base: www.kb.vmacair.com
61
Compressor Regulation and Throttle
Actuator Testing
Throttle Control
VMAC configures the Honda engine throttle to be wide open in its neutral
state (0 psi). Engine rpm is controlled via the throttle actuator which is
operated by air pressure from the unloader valve.
Once air pressure at the ball valve and unloader valve (“downstream
pressure”) reaches 150 psi, the throttle actuator closes the throttle, reducing
engine speed to idle. “Downstream pressure” opens the discharge valve
diaphragm, via the 1/4 in PTFE tube, and allows air pressure to close the inlet
valve poppet (Figure 44, Figure 45, Figure 46).
Figure 44
– Throttle operation
Figure 45
– Throttle operation
Steady system pressure
to inlet regulator
(0-150 psi)
Tool pressure
System pressure
once discharge
valve diaphragm
opens at 150 psi
Throttle
lever
Throttle
actuator
Unloader
valve
Discharge
valve