• Loading solenoid valve (Y1).
• The Base controller that regulates the compressor based on the pressure settings and
readings of the pressure sensor.
Loading
If the working pressure is below the preset maximum, the solenoid valve (Y1) is energized and
therefore closed. There is no signal air flow into unloader allowing the inlet valve to open due to
the element suction.
The inlet valve opens completely allowing the air through the air filter (AF) and the compressor
will run fully loaded (100% output).
The unit stops loading when the set ‘Unload’ pressure is reached, the machine will run unloaded.
Unloading
When the working pressure reaches the maximum limit, the solenoid valve is de-energized,
venting the control air: the inlet valve closes completely and the unloading valve opens
completely. The compressor will run unloaded (0% output).
The G 15L, G 18 and G 22 are equipped with an intelligent controller that will stop the
compressor after a variable period of unloaded operation using the following control algorithm:
• At power on, in the first work cycle, the ‘Unload’ period is 30 seconds.
• After the first work cycle, and in all other working cycles, the ‘Unload’ period is calculated
following 3 rules:
a. Given a maximum number of 10 restarts per hour (factory setting), the total running
period per cycle (‘Load’ time + ‘Unload’ time) must be minimum 6 minutes (360s).
b. At the end of the unload period the controller checks the air consumption and decides
whether to stop the unit or restart to anticipate the air demand.
c. Motor virtual temperature calculation.
If the unit is restarting frequently, or is manually restarted by the operator, the controller
will extend the unload period in order to ensure proper motor cooling. This overrules the
standard unload period.
The compressor will automatically restart when the net pressure drops to the minimum limit.
The compressor will automatically restart when the net pressure drops to the minimum limit.
2.6
Control panel
Instruction book
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Summary of Contents for G 15L
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