Doosan 10/370, Operation And Maintenance Manual

Page: 45 / 96

Operating Instructions Operating & Maintenance Manual
45
Normal Operation
The Operator may observe and monitor operating parameters using the gages on the panel.
In the event the machine controller detects a parameter outside normal operating limits, the
unit will shutdown.
In the event the machine controller detects a parameter at a dangerously high or low level, the
machine will be automatically be stopped with the cause of the SHUTDOWN shown on the
diagnostic lights and display.
Delivered air volume at set point pressure is accomplished by two methods:
1. The compressor is loaded (inlet valve fully open or modulated partially open) or
unloaded (inlet valve fully closed).
2. Engine speed varies between 1200 RPM and 1800 RPM while compressor is
loaded to match the required volume flow.
Operation - Loaded
Assume engine has been started and is running in the unload state at 1200 RPM. If there is
air demand (pressure falls below the load point pressure), compressor will load at 1200 RPM
by opening the inlet valve. As air demand rises and falls, engine speed is controlled between
1200 RPM and 1800 RPM to match the required flow while maintaining rated pressure.
Operation - Unloaded
If there is no air demand at 1200 RPM (pressure rises above the unload point pressure), the
compressor will unload by closing the inlet valve. The unit then runs at 1200 RPM unloaded
with no air delivery. If air demand increases (pressure falls below the load point pressure), the
compressor reloads to meet the required air demand.
Stopping
• Close air service valve(s).
• Allow the unit to run at “IDLE” for 3 to 5 minutes to reduce the engine temperatures.
• Turn the keyswitch to the “OFF” position.
NOTICE
Failure to allow turbo cool down prior to stopping can cause
turbocharger damage.