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The Proviso™ Plus P300

The Proviso™ Plus P300 system is designed for controlling the self-steering lift axle on SPIF 21 and 23 trucks. This includes lifting the axle in reverse, with the 4-way flashers, and when the truck is empty. The system also lowers the axle when the truck is loaded.

The P300 monitors the weight on the steer and tandem axles and control the lift axle weight. When the front weight is too low, the P300 can reduce the weight on the lift axle to regain steering ability.

The P300 also provides an in cab display of the weight, current limits, axle position, and status of the system.

Features

  • In-Cab Weight display
  • Maintains front axle %
  • Lifts the truck’s self-steering axle while reversing.
  • 4-way lift functionality
  • Automatically lifts and lowers based on weight
  • Manual override to lift the axle

How it works

Reverse Lift

The reverse lift feature uses the Wheel Monitor Reverse Sensor to determine the trucks direction. When the truck has reversed approximately 8 inches, the reverse lift feature activates. The Reverse lift feature remains active until the truck moves forward 50 feet without stopping. The forward distance setting can be altered.

4-way Lift Feature

The 4-way lift feature can be activated by the driver at anytime, when traveling under 60km/h. The feature is activated by turning the 4-way flashers ON. The 4-way lift feature will deactivate if the 4-way flashers are turned OFF, the disable button is touched on the screen, or the truck travels above 60km/h.

Load Control

The load control feature can lift and lower the lift axle based on the load condition of the truck. The P300 offers multiple sensor types and configurations to measure the load condition of the truck. During the installation process, the system is programmed with a sensor reading to weight calibration. When correctly calibrated, the system will automatically detect load changes and deploy the axle when all the requirements are met. The requirements are defined by SPIF, including a minimum lift axle weight and a minimum front axle percentage of gross weight. 

Lift Axle Weight Control

When the Lift axle is lowered, the P300 will control the pressure applied to the lift axle suspension. The P300 can alter the pressure, which in turn alters the weight carried by the lift axle. The pressure is regulated to reach the highest allowable gross weight while maintaining the required front axle percentage of gross weight and the minimum lift axle weight, define by SPIF.

The P300 will reduce the lift axle weight to ensure the front percentage of gross weight is maintained. In some cases, reducing the pressure is not enough and the axle must be lifted to reach the minimum percentage.

Calibration Offset

The P300 is indirectly measuring the load condition of the vehicle. It relies on several of the trucks components performing in a very repeatable manner. When one of these components shifts or performance changes, the weight calibration may change. The P300 offers a calibration offset or “TARE” feature. When the feature is activated, the system adjusted the calibration to match the trucks current condition. It is important the calibration offset procedure is followed correctly and is only done while the truck is empty.

In-Cab Display

The P300 offers an in-Cab display with a touch screen. The display allows the driver to see the current weight measurements of each axle group, the front percentage, the gross weight, and the system’s status. The display also offers several buttons for restarting the system, TARE the calibration, and 4-way lift operation.

Comparisons

P200A P200ML P300
Reverse Lift
Reverse Lift
Reverse Lift
4-way Lift
4-way Lift
4-way Lift
Load Control
Load Control
Load Control
60km/h Steer Lock
60km/h Steer Lock
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PC Interface
PC Interface
PC Interface
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-
Weight Display
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-
Front Axle Weight
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Front % Management

Documentation

P300 Kits

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