770, 772, 773E, 773F, 777E and 777F Off-Highway Trucks and 775F Quarry Truck VIMS Truck Payload System Caterpillar

VIMS/TPMS Electronic Control Module (ECM)

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A5:N2 ECM for 777E and 773E

The VIMS/TPMS ECM is the brain of the TPMS. All computing and storage of the cycle data takes place in the VIMS/TPMS ECM. The VIMS/TPMS ECM receives input signals from the four suspension cylinder pressure sensors. The VIMS/TPMS electronic control module processes the input signals from the four suspension cylinder pressure sensors. The VIMS/TPMS electronic control module converts the payload signals into a digital equivalent value. The VIMS/TPMS ECM uses this information in the TPMS.

Messenger Module

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Messenger Module for 770, 772, 773F, and 777F Off-Highway Truck/Tractors, and 775F Quarry Truck

The stand-aloneTPMS uses the Messenger to display the calculated weight of the payload. Text messages on the message center tell the truck operator when the target payload weight has been reached.

Advisor Module

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The VIMS/TPMS uses the Advisor to display the calculated weight of the payload. Text messages on the message center tell the truck operator when the target payload weight has been reached.

The Instrument Cluster module indicates when the transmission has shifted into second gear. The Second Gear Reweigh Function then starts.

Buttons of the Display

The Messenger/Advisor buttons interface with the VIMS. The operator can perform the following functions of the TPMS with the buttons of the display:

• Change the display units. The payload information can be displayed in English units or Metric units.

• Modify the target payload weight of the truck. (The Service Tool must be connected.)

• Turn ON the last pass indication.

• Turn OFF the last pass indication.

• Enter an operator identification number. A pit identifier for each load can be entered in the place of the operator identification number.

• Calibrate the system. (The Service Tool must be connected.)

• Clear resettable totals.

Pressure Sensors of the Suspension Cylinder

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The four pressure sensors of the suspension cylinder convert the payload into a signal that is proportional to weight. This signal is then passed to the VIMS electronic control module.

Payload Status Lamps

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The payload status lamps are on both sides of the truck. The payload status lamps show the loader operator when the target payload weight has been reached. The VIMS TPMS allows the truck operator to configure the payload status lamps to indicate the last pass. The payload status lamps will illuminate the following colors.

• A green lamp signals the “loader operator” to continue loading the truck.

• A flashing red lamp tells the “loader operator” that one additional pass is required to load the truck to capacity.

• A steady red lamp signals the “loader operator” that the target payload weight has been reached or exceeded.

External Payload Display

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The external payload display is a 356 mm × 686 mm (14 inch × 27 inch) screen. The external payload display is mounted on the side of the truck. The external payload display provides the operator of the loading tool with the measured weight of the material that is currently in the body of the truck. The payload information is displayed in 254 mm (10 inch) red digital numbers. There are three configurations of the external payload display that are available. These configurations are listed below:

• Dual Displays (right-hand and left-hand displays)

• Right Display (right-hand display)

• Left Display (left-hand display)

The external payload display receives data through the VIMS broadcast (system telemetry) port. There are two modes of operation. The modes of operation are listed below:

Single Mode - This mode is for machines that are not equipped with a radio telemetry system.

Passive Mode - This mode is for machines that are equipped with a radio telemetry system. This mode allows the display to access data for the payload weight without interfering with the operation of the radio telemetry system.

Transmission ECM

The transmission ECM converts the following conditions into a digital equivalent value: body position, ground speed, transmission gear and parking brake. The transmission ECM then passes the information to the VIMS/TPMS ECM over the Cat Data Link for use by the Truck Payload Measurement System.

Electronic Control Module (Engine)

The engine control module calculates fuel flow. The control converts this data into a digital equivalent value. The engine control module then passes the information to the VIMS/TPMS ECM over the Cat Data Link for use by the TPMS.