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Illustration 1 | g03665022 |
Rear of Vehicle (1) Water pressure sensor |
Water pressure sensor (1) is generally located in the spray bar on the rear of the vehicle.
Water pressure sensor (1) is a pressure sensing device with analog output. The rear-mounted XA2-A1 provides a common ground and a 5-volt reference power supply to the sensor and collects the analog signal. The XA2 module transfers the signal to the display via CAN lines. The display control system determines water pump output pressure using water pressure sensor signal voltage. The display then uses the data with a combination of selected and programmed parameters in order to provide the appropriate water pressure.
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Illustration 2 | g03665037 |
Example of Electronic Control Group (2) WDS module enclosure (3) XA2 CAN module (4) Relays (5) Wiring receptacles |
The WDS utilizes three electronic control groups. The electronic control group shown is typical. The first is located at the rear of the vehicle, mounted on the rear of the water tank or on the rear chassis. The second group is located in the vehicle cab. The third group is located at the front of the water tank.
The front and rear exterior electronic control groups are encased in WDS module enclosures (2) with hinged covers. These enclosures contain XA2 CAN modules (3) and relays (4). These groups are also fit with through-case wiring receptacles (5) in order to connect with system wiring harnesses. The cab electronic control group is similar, however the enclosure is suited to interior mounting.
The rear electronic control group houses the XA2-A1 module. This module communicates with:
- Pressure sensor (water)
- Tank level sensor (water)
- Motor inlet pressure sensor
- Remote enable switch
- Rear spray head solenoids
- CAN-A (display control)
- AUX dump bar/drain valve solenoid
- Hose reel soap pump
- Hose reel soap pump switch
The cab electronic control group houses the XA2-A2 module. This module communicates with the following devices:
- CAN-A (display control)
- CAN-B (keypad and joystick)
- Hydraulic temperature sensor
- Hydraulic oil tank level sensor
- Hydraulic oil filter switch
- Hoist solenoids for tank lift
- Hydraulic pump solenoid
- Fan relay (hydraulic cooler)
- Tank-fill open and close relays
- CAT ECM CAN-B
The front electronic control group houses the XA2-A3 module. This module communicates with the following devices:
- CAN-A (display control)
- Front or side spray head solenoids
- Water cannon up and down solenoids
- Water cannon left and right solenoids
- Water cannon valve solenoid
- Nozzle volute motor
- Additive system solenoid fluid "A"
- Additive system solenoid fluid "B"
Sealed WDS module enclosure (2) protects the internal components from external environmental impact.
Module enclosure (2) provides wire connections for the following:
- Electrical power
- Sensor and module signals
- Relays (4)
There are six relays (4) in the system. The relays are controlled by the system. The relays provide switching functions to the hydraulic cooling fan, tank-fill start and stop, cannon volute open and close and optional additive system pump.
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Illustration 3 | g03665091 |
Cab Fuses (6) 777F fuses (7) 777G fuses (8) 785D fuses |
The WDS electrical loads are divided between fuses. The fuses on each machine are located inside the cab.
All models have two 15 amp fuses and one 10 amp fuse. One 15 amp fuse is for the hydraulic cooling fan. The second 15 amp fuse is for the remaining WDS system. The 10 amp fuse is used for the WAVS washer pump. The fuses are fed 24 V by the switched power source within the cab fuse box.
The hydraulic fan fuse receives power from the switched power source in the fuse box. This power is transferred through the fuse to the cooling fan wiring.
The WDS system fuse receives power from the switched power source in the fuse box. This power is transferred through the fuse to the WDS wiring.
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Illustration 4 | g03665098 |
At Low Point of Tank on Front or Rear Face (9) Water tank level sensor |
Water tank level sensor (9) is located in the WDS water tank. The system uses this pressure-sensitive sensor in order to determine the water level. The sensor is located at a low point on the tank, on the front or the rear face. The specific location of the sensor may vary between tank manufacturers.
Water tank level sensor (9) generates an analog output. The rear-mounted XA2-A1 provides a common ground and a 5-volt reference power supply to the sensor. This XA2 module also collects the analog signal. The XA2 module transfers the signal to the display via CAN lines. The display control system determines the level of water in the tank using the input signal.
Water tank level sensor (9) operates by detecting pressure. When the water tank is empty, the sensor detects no pressure and transmits a low signal voltage. When the water tank is full, the sensor detects high pressure and transmits a high signal voltage. The sensor is analog and will signal with a voltage proportionate to the pressure received by the sensor.
The signal data of water tank level sensor (9) is processed by the display into a scaled percentage for display to the operator. The data is also used as reference for the following:
- Tank filling operations
- Low water warning
- Automatic water pump shutoff when empty level is detected in-conjunction with low water system pressure