Ingersoll-Rand HP915WCU, Operation & Maintenance Manual

Page: 80 / 101

Operating & Maintenance Manual Machine Systems
80 Book: 22846430 (8-21-06) Rev. A
General Information and Operational Theory
General
The mid-range machine has an electronic monitor and control system to provide discharge air
pressure control and engine and package monitor functions. The system uses the WEDGE
controller to perform these functions. The electrical system connects all the necessary
switches, sensors and transducers to the WEDGE controller in order for it to perform the
monitor and control functions. See drawing 22839591 for an overview of the control schematic.
Wedge Controller
The WEDGE controller is the heart of the machine monitor and control system. It provides data
collection, alarming and control functions for compressor operations. It is a microcontroller
based unit with analog and digital inputs and outputs.
The WEDGE controller is attached to the back of the control panel. The LED annunciators are
part of the front panel of the WEDGE. They can be seen through the laminate on the front of
the control panel. The WEDGE is attached to the control panel with four #10 size nuts.
The first function of the WEDGE controller is to scan all analog and digital inputs at a fixed
interval. These inputs are scanned every 50 milliseconds. The analog values are then
compared against minimum and maximum values and an ALERT or SHUTDOWN is issued,
if a value is out of range.
The various ALERTS and SHUTDOWNS are listed in the Operation Instructions Section of this
manual.
The second function of the WEDGE controller is machine discharge pressure control. The
WEDGE monitors the regulation system air pressure and varies the engine throttle to maintain
the setpoint discharge air pressure. The setpoint pressure is set using the regulator on the
separator tank.
The third function of the WEDGE controller is to communicate with the diesel
engine via the J1939 CAN network. It retrieves diagnostic information over the J1939.