32
CMC TECHNICAL REFERENCE MANUAL
1X36003 Version 2.52
1996-1999 Ingersoll-Rand Company
Date of Issue: 18-Oct-1999
4/6
SYSTEM
SETTINGS
INFO
Loaded
Remote
Load Selected
Modulate
Autodual
Reload Pressure, % of Setpoint 98
Unload Point, BV % Open 1
Unload Delay Timer, seconds 1
Manual
Control Mode
Settings Folder - Page 4: Control Mode Selection
Each It (Proportional Band)
repeats/second
0.0
99.99
0.1
Each D (Proportional Band)
seconds
0.0
99.99
0.1
CAUTION
Setting the Derivative parameter to a value other than zero for any of the PID
settings may cause the valve output to change rapidly. Please change this value with
caution.
The Control Mode Selection Page
allows the User to select between
the two standard control modes,
Modulate and Autodual. This
selection process is performed
with the radio button selector. To
change the selection, press the
Up or Down arrow key.
Reload Percent, Unload Point and
Unload Delay Time are all
setpoints for Autodual control.
Checking the Manual checkbox
enables manual valve control. In this mode, the inlet valve may be stroked when the
compressor is not running, and the bypass valve can be stroked at any time. If a surge
condition occurs while manually controlling these valves, the CMC will automatically take
over the valves.
Settings Folder Page 4 Edit Parameters Table
Variable
Units
Minimum
Value
Maximu
m
Value
Step
Size
Autodual Reload Pressure
% of Setpoint
0
99
1
Autodual Unload Point
BV % Open
1
99
1
Autodual Unload Delay Timer
seconds
0
999
1
CAUTION
Manual should only be used for compressor setup.
Starting Timer is the length of time prior to enabling the loading of the compressor. Typically,
this time includes the starter transition time (Y-D time). When this timer expires, the prelube
pump will turn off and the compressor is enabled for loading.
