Jacobsen Eclipse 322, Repair Manual

Page: 123 / 336

ELECTRICAL
4222983 Second Edition 4-49
4
Mow Circuit—Theory of Operation
Power Circuit
Unswitched 48V power is available from stud 3 through
150A fuse (F8) and 0.02 ohm resistor (R6) to key switch
terminal A and liquid crystal display (LCD) terminal
J11-8.
When the key switch is turned to the run position, 48 volts
is provided from key switch terminal B to liquid crystal
display (LCD) ignition terminal J11-5, powering up the
LCD.
With the LCD powered up, a ground is provided from the
LCD switched power contactor output terminal J11-10 to
the power distribution unit (PDU) terminal J1-4. With a
ground provided to J1-4, the 12 and 48 volt switched
power contactors are energized.
With the PDU 12 volt switched power contactor
energized, 12 volts is provided through 0.02 ohm resistor
(R12) to the main control unit (MCU) 12 volt power input
terminal J2-8. PDU terminal J1-5 also provides 12 volts
to splice E and then from splice E, 12 volts is provided to
MCU 12 volt power input terminal J2-6. With the PDU 48
volt switched power contactor energized, 48 volts is
provided to circuit breaker (F4) and MCU 48 volt power
input terminal J2-7, powering up the MCU.
Forty-eight volts is provided from PDU terminal J122 to
reel control unit (RCU) 48 volt power input terminal J5-3,
powering up the RCU.
The LCD converts the 48 volts supplied to LCD terminal
J11-8 to 12 volts. The 12 volts is used as the source
voltage for the control panel switches and seat switch.
LCD +12V power supply terminal J11-6 provides 12 volts
to splice G. Splice G provides 12 volts to seat switch
terminal J41-1.
Mow Circuit
The right, center, and left reel enable switches allow the
operator to choose which reels to operate. (See
“Raise/Lower Circuit—Theory of Operation” on
page 4-41.)
When the mow switch is in the on position, voltage is
provided to the LCD mow switch input J12-5, activating
the input. With the mow switch input activated, the status
of the switch is communicated to main control unit (MCU)
through the controller area network (CAN).
The operator must be on the seat before the main control
unit (MCU) allows the reel motors to operate. With the
operator on the seat, voltage is provided from seat switch
terminal J41-2 to MCU seat switch input terminal J4-10,
activating the input.
When the raise-lower switch is placed in the lower
position, voltage is sent to the LCD lower input J12-8.
The LCD then communicates the status of the switch to
MCU. (See “Raise/Lower Circuit—Theory of Operation”
on page 4-41.)
With the mow, seat, and lower switch inputs activated,
the MCU now instructs the reel control unit (RCU) to
lower the selected reels and activate the reel motors.
Note: with the FOC mode set to a value other than zero
the reels will not turn until the traction pedal is depressed.
The right, center, and left reel motors are all identically
controlled by the RCU. The right reel motor will be used
to describe the theory of operation.
The RCU 48V right reel motor power output terminal
J9-C provides 48 volts to right reel motor 48V power input
terminal J22-1, and the reel motor begins to rotate.
The RCU right reel motor CW/CCW signal output
terminal J8-9 connects to the right reel motor CW/CCW
input terminal J69-1. The RCU reel motor CW/CCW
signal output allows the machine to have the flexibility of
having the motor mounted to right or left sided of the
cutting unit. With no output to the reel motor, the motor
rotates counterclockwise. When the output is providing a
signal to the reel motor, the motor rotates clockwise. The
MCU checks the CW/CCW mode setting stored in the
LCD and instructs the RCU which direction to rotate the
reel motor while cutting.
The RCU right reel motor speed signal output terminal
J8-10 provides a signal to the right reel motor speed
signal input terminal J69-3, controlling the speed of the
reel motor. Reel motor speed is set via the LCD.
The right reel motor tachometer output terminal J69-2
provides a signal to the RCU right reel motor tachometer
input terminal J8-3. The MCU receives the data from the
RCU and then the MCU sends the data to the LCD.
The right reel motor temperature output terminal J69-8
provides a signal to the RCU right reel motor temperature
input terminal J8-7. The RCU uses this signal to
determine the temperature of the reel motor. MCU
receives the data from RCU and then the MCU sends the
data to the LCD.