Ingersoll-Rand HP1300WCU, Руководство по эксплуатации, техническому обслуживанию и каталог запасных частей

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Book 54757919 (5/02)
SECTION 8 -- ELECTRICAL
GENERAL INFORMATION AND OPERATIONAL
THEORY
General
The HP1600/1300 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.
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 opera-
tions. 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 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 SHUT-
DOWNS are listed in this section.
The second function of the WEDGE controller is ma-
chine discharge pressure control. The WEDGE moni-
tors the regulation system air pressure and varies the
engine throttle to maintain the setpoint discharge air-
pressure. The setpoint pressure is set using the regu-
lator on the separator tank.
The third function of the WEDGE controller is to com-
municate with the diesel engine via the J1939 CAN
network. The WEDGE controller provides the engine
throttle setting (software versions 2.0 and greater) to
the engine controller via the J1939 CAN Network and
retrieves diagnostic information from the engine.
Software versions under 2.0 use the frequency throttle
to communicate with the engine. A square wave fre-
quency signal from 150 Hz to 375 Hz is sent from the
WEDGE controller to the engine controller.
The signal is linear from 150 Hz at engine idle (1200
RPM) to 375 Hz at maximum run speed (1800 RPM).
Figure 8--2 shows the signals between the engine con-
troller and the WEDGE controller.
Sensors and Transducers
The electronics system contains sensors and trans-
ducers that are used to collect process data from the
compressor. The temperature is measured by a ther-
mister. This device exhibits a change in resistance as
the temeprature changes. The resistance causes an
input voltage change to the WEDGE controller input
and is interpreted as a temperature change.
The electronics system also uses pressure transduc-
ers to measure process pressure changes. These de-
vices have an output signal of .45 VDC to 4.5 VDC,
corresponding to 0 psi and the maximum measured
psi for a particular device. The maximum pressure
transducer ranges are 100 or 225 psi. The 100 and
225 psi devices are gauge rpessure devices. These
transducers are provided with 5VDC excitation to pow-
er the device. These are three wire devices: excita-
tion, signal and ground (return) connections.
Digital Inputs and Outputs
The WEDGE controller scans digital inputs such as
switch contacts. These are either “ON” (24VDC) or
“OFF” (0 VDC). These digital inputs are connected to
switches within the package such as the key start
switch, air filter switches and IQ filter switches.
The WEDGE controller provides 24 VDC digital out-
puts to control solenoids, start compressor and DC
heaters. These are 24 VDC “ON” and O VDC “OFF”.
They are current limited and short circuit protected.