SECTION 5 DE-18 USER MANUAL
55
The engine speed will be controlled by the PTO
increase and PTO decreases speed outputs to
maintain the discharge pressure at the setpoint
pressure.
The PTO speed control outputs are tuned by the
following Adjustments.
The RPM Deadband (P-15 adjustment) setting is
used to create a deadband (an inactive area) of
throttling around the Minimum RPM (P-13
adjustment). The engine speed is inherently an
unstable signal and will drift back and forth across
the true speed setpoint. This is further agitated with
valves opening and closing. This deadband
minimizes the instability's effect on the load
sequencing.
The Upper and lower Deadband settings (P-50 & P-
49 adjustment) are used to create a deadband (an
inactive area) of throttling around the Setpoint
Pressure. When the discharge pressure is below the
Setpoint Pressure minus the Lower Deadband
Pressure (P-49 adjustment), the Engine speed will
be increased. When the discharge pressure is above
the Setpoint Pressure plus the Upper Deadband
Pressure (P-50 adjustment), the Engine speed will
be decreased.
Load Pressure (S-14 adjustment) is the pressure
relative to the Setpoint Pressure where that the
compressor will be loaded. When the discharge
pressure drops to the Setpoint Pressure minus the
Load Pressure Setpoint the air intake solenoid will be
energized to open, loading the compressor.
Unload Pressure (S-13 adjustment) is the pressure
relative to the Setpoint Pressure where that the
compressor will be unloaded. When the discharge
pressure rises to the Setpoint Pressure plus the
Unload Pressure Setpoint the air intake solenoid will
be de-energized to close, unloading the compressor.
The Throttle Minimum Pulse setting (P-16
adjustment) is used to adjust the minimum pulse
detectable by the throttling system.
The Throttle Maximum Pulse setting (P-17
adjustment) is used to adjust the maximum pulse
sent to the throttling system.
The Throttle Sensitivity setting (P-19 adjustment) is
used to adjust the overall gain or speed of the
throttling system.
The Throttle Feedback Delay (P-18 adjustment) is
used to delay further action by turning the increase
and decrease outputs OFF for this amount of time.
This gives the engine a chance to respond and the
pressures a chance to settle for a proper sampling
value.
The Speed Control PID's Proportional Setpoint (P-57
adjustment) calculates the ON time for the increase
and decrease outputs. This proportional setpoint
influences the PlD directly, the farther the controlled
value is away from the setpoint the longer the ON
time period towards the setpoint by the weight of this
factor. This function is most useful for normal PID
applications.
The Speed Control PID's Integral Setpoint (P-58
adjustment) influences the PlD accummulatively, the
longer the controlled value is away from the setpoint
the longer the ON time period towards the setpoint
by the weight of this factor. Also this function may
produce oscillation if the value is too high.
The Speed Control PID's Derivative Setpoint (P-59
adjustment) influences the PID's acceleration; this
controls the compensation to acceleration in order to
hit the setpoint faster by the weight of this factor. This
function is used with fast controls that tend to
overshoot their setpoint and may also produce
oscillation if the value is to high.
The Unload Gain Speed (P-60 adjustment) controls
the unload time verses load time. This function is
used with a control that you wish the unload time to
be longer or shorter than load time (a setting of 1.0
being the same time).
While running, the drain solenoid valves will be
energized to open for 3 seconds (S-4 adjustment),
and de-energized to close for 2 minutes (S-5
adjustment). This will happen the entire time the
compressor is running after the engine has warmed-
up, and before the engine is in a cooldown stop.
At any time the controller is powered-up, the setpoint
pressure can be changed by pressing the increase
setpoint pressure push button, or by pressing the
decrease setpoint pressure push button.
To Next Page
Loading...
