Atlas Copco PTS 916 Cd Instruction Manual page 26

PTS 916 Cd
Unload RPM Control
It allows compensation of engine power at high altitude
applications.
In the Unload condition the engine will run at the Unload RPM.
In the Load condition the engine will not run slower than the
Unload RPM. If the Unload RPM parameter is enable, it is possible
for the user to change the Unload RPM with the UI.
Loading Valve Control
When the compressor is going to the load condition, and the engine
RPM setpoint is above 1420 RPM the loading valve is opened
when the engine reaches 1400 RPM.
If the engine RPM setpoint is below 1400 RPM, the loading valve
is opened at the engine RPM setpoint - 20 RPM.
Pressure Calibration
To compensate the offset error of the Air Discharge Pressure
sensor, a Pressure Calibration parameter is implemented.
The offset error is measured by comparing the sensor value with
that of a verified and stamped pressure gauge.
This parameter is programmed with the value that compensates the
error.
Ex. Pressure gauge value: 7.8 bar
Sensor value: 8.1 bar
Parameter value: - 0.3 bar
Poweroff
When the power is switched on, a Wrong Poweroff flag is set.
When the power is switched off when the engine is not running, the
Wrong Poweroff flag is reset.
When pressing the emergency stop, the programs of the CCM and
the UI keep on running, but the power to the outputs is cut off, so
the engine will stop immediately.
When the power is switched off then, the Wrong Poweroff flag is
reset.
When the power is switched off while the engine is running, the
programs of the CCM and the UI will keep on running and the
CCM will stop in a controlled manner (cooldown - stopping
procedure), before it will Powerdown and reset the Wrong
Poweroff flag.
When the power is switched off as well as the emergency stop is
pressed, no power supply to the CCM is left and the engine cannot
be shut down properly. The Wrong Poweroff flag is not reset.
When the power is then switched on again, the Wrong Poweroff
counter will add 1.
Executing a wrong poweroff can result in memory damage.
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Powerdown
To save the batteries, the CCM and UI are equipped with a
Powerdown function.
When the compressor is not running and the Automatic start is not
activated, the CCM and UI will go to Powerdown mode if there has
not been any action during the Powerdown time.
In Powerdown mode the CCM and UI will perform as little as
possible to reduce the power consumption. The screen of the UI
will therefore be shut down.
Local control mode
When a button is pressed on the UI, the CCM will return to its
previous status.
Remote control mode
When the compressor is in the Ready for Start status and the
Remote start button is pressed, the CCM will come out of
Powerdown and go directly to the Permissive Start or Standby
status. Pressing any other Remote control button (except Remote
ON), will only result in deactivating the Powerdown, also when the
CCM is in any other status.
When the Remote ON input is not active, none of the Remote
inputs can deactivate the Powerdown.
When a button on the UI is pressed, the CCM will come out of
Powerdown.
When there has not been any action during three minutes, the CCM
will return to Powerdown.
PC control mode
When an action is performed via the PC, demanding a response
from the CCM or UI (Start signal, changing settings, ...), the CCM
will come out of Powerdown.
When a button on the UI is pressed, the CCM will come out of
Powerdown as well.
When there has not been any action during three minutes, the CCM
will return to Powerdown.
Air Discharge Temperature Control (optional)
By changing the temperature of the cooling air going through the
aftercooler it is possible to heat the discharge air to a certain setting.
This is done with a proportional valve controlled with a PWM
signal, and mounted on a cooler.
The Air Discharge Temperature Control becomes active after the
Warmup status, and stays active for as long as the engine is
running. The operation of the Air Discharge Temperature Control
depends on the Air Discharge Temperature Control Parameter.
Preliminary