Common Requests

Technical Bulletins

Bulletin 151002 - Verifying System Performance

Attention owners and operators of Proviso Plus P200A, P200M and P300 control systems.
We would like to stress the importance of verifying that the Proviso Plus control system is working correctly.

This includes:
• Checking that the axle lifts and lowers at the correct times.
• Checking that the Lift Axle is equalized when lowered. (Carrying the correct weight)

To check that the lift axle is equalized, we recommend weighing the truck while the axle is down using the following procedure:
1. Weigh the rear 3 axles. (lift axle and the tandems, lift axle must be lowered)
2. Weigh the tandems only. (lift axle must be lowered)
3. Subtract the second weight from the first weight to determine the lift axle weight.
4. Determine if the lift axle is equalized or not.
a. SPIF Schedule 23: the lift axle must carry 50% of the tandem weight +/-500kg
b. SPIF Schedule 21: the lift axle must carry 33% of the tandem weight +/-500kg

Checking the lift axle pressure regularly can help indicate when the systems performance needs to be verified. The lift axle pressure should stay within a normal range. If the pressure is outside that range, we recommend verifying the systems performance.

If the lift axle is not within equalization, the control system's calibration needs to be adjusted. This can be done with the "Reset" switch/button, if the system is equipped with one. This can also be done by any NSM installer.

Note: Verify the systems performance as often as possible. At least once a month is recommended.

Verifying the systems performance on a regular basis will reduce the risk of fines based on equalization.

Please contact Wheel Monitor if you have any questions or concerns."


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