Caravanning Hints & Tips
Horses For Course When It Comes To Having The Car And Caravan Weighed
02 September 2024
HORSES FOR COURSES We are often asked “why should I have my car and caravan professionally weighed by a mobile weighing service when a trip to a public weigh bridge will do the same?”The quick answer is that it depends on what you are trying to achieve. If you are just wanting to validate your expected or known weights (GCM, GVM, GTM, ATM, TBD) then yes, a public weigh bridge is fine. But they do have their limitations. If you are weighing for the first time, a professional mobile weighing service may be a more appropriate option for you. A weigh bridge will not provide enough information to give a full and accurate account of load distribution across both car and caravan. If your caravan feels unsettled or sways when towing a public weigh bridge will not be able to provide sufficient data for you to make a qualified decision on how to identify or go about rectifying the issue. In which case a reputable mobile weighing service will be a better option for you. Both provide value for money. It really is a case of horses for courses.Well, let us have a look at the facts and break down the pros and cons of both the public weigh bridge and the professional mobile weighing service.
ACCURACY OF RESULTS:In good operations both the public weighbridge and mobile weighing operator will have their equipment inspected and calibrated at least annually. So, you can be confident that the results you receive will be true and within the manufacturers tolerances.The results of a public weighbridge need only be displayed in 20kg increments. This means that the displayed result of each load area has a tolerance of (+or-) 10kg. So, when you have 3 load platform readings, the acceptable result is (+or-) 30kg. Therefore, the overall result can be up to 60kg out and still be within manufacturers tolerance.Quality scales, used for mobile weighing, normally display their results in 1kg increments or (+or-) 500g. Given each wheel is weighed separately, the overall result tolerance for a single axle caravan can be up to 6kg and a dual axle caravan 8kg respectively to be considered within manufacturers tolerance.This difference is critical when it comes to determining tow ball download (TBD). On a weighbridge, two load platforms are used to calculate the tow ball download. Using the formula above you can expect your result to be accurate to within a range of 40kg. When you usually only have a 350kg allowance from your vehicle manufactured this provides an accuracy rate of just 89%. On the other hand, your mobile weighing service uses four scales with an overall 8kg or based on a 350kg allowance, 2% margin for error.
FULLNESS OF RESULTS:Most public weigh bridges only use three load platforms to weigh a car and caravan. In this limited configuration they can only provide axle weight totals. This means that they measure weight from front to back and not left to right. Therefore, you will not know if your car and caravan are balanced from one side to the other. Further, the public weigh bridge can only weight the caravan axles as a group. So, if you have a dual or tandem axle caravan you will not be alerted to having one axle carrying significantly more weight than the other on your caravan. These can be critical factors when it comes to overall caravan towing stability and safety. INTERPRETING RESULTS:Checking to see that your results are within the weight limitation of your car and caravan is a straightforward process within the capability of most people. Determining and understanding the acceptable parameters for weight distribution is a different thing. A professional mobile weighing service operator will have weighed 100’s if not 1000’s of cars and caravans or have access to someone who has. This experience places them in a position to readily identify weight distribution issues and how they can potentially impact on each other. ADVICE AND RECOMMENDATIONS:Many public weigh bridges are unmanned or at best operated by someone who knows how to work the weigh bridge but is not familiar with or have an in-depth knowledge of car and caravan weighing. A professional mobile weighing service on the other hand, having interpreted the results of your weighing data, will be able to give you your options regarding solutions to any identified weight distribution issues. They will also have a network of industry contacts to provide any specialised services that may be needed. The likes of engineers and suspension experts for ATM and GVM upgrades. SUMMARY:While it is important to know that you are under all your weight matrix limits, it is something else to know that you have your weight distributed and your car and caravan set up for optimal towing stability and safety.A car and caravan that is under all the weight limits is compliant and roadworthy, However, if weight is not properly distributed across both car and caravan it is not necessarily safe.Horses for courses, it all depends on what you want to achieve from your car and caravan weighing.
FULLNESS OF RESULTS:Most public weigh bridges only use three load platforms to weigh a car and caravan. In this limited configuration they can only provide axle weight totals. This means that they measure weight from front to back and not left to right. Therefore, you will not know if your car and caravan are balanced from one side to the other. Further, the public weigh bridge can only weight the caravan axles as a group. So, if you have a dual or tandem axle caravan you will not be alerted to having one axle carrying significantly more weight than the other on your caravan. These can be critical factors when it comes to overall caravan towing stability and safety. INTERPRETING RESULTS:Checking to see that your results are within the weight limitation of your car and caravan is a straightforward process within the capability of most people. Determining and understanding the acceptable parameters for weight distribution is a different thing. A professional mobile weighing service operator will have weighed 100’s if not 1000’s of cars and caravans or have access to someone who has. This experience places them in a position to readily identify weight distribution issues and how they can potentially impact on each other. ADVICE AND RECOMMENDATIONS:Many public weigh bridges are unmanned or at best operated by someone who knows how to work the weigh bridge but is not familiar with or have an in-depth knowledge of car and caravan weighing. A professional mobile weighing service on the other hand, having interpreted the results of your weighing data, will be able to give you your options regarding solutions to any identified weight distribution issues. They will also have a network of industry contacts to provide any specialised services that may be needed. The likes of engineers and suspension experts for ATM and GVM upgrades. SUMMARY:While it is important to know that you are under all your weight matrix limits, it is something else to know that you have your weight distributed and your car and caravan set up for optimal towing stability and safety.A car and caravan that is under all the weight limits is compliant and roadworthy, However, if weight is not properly distributed across both car and caravan it is not necessarily safe.Horses for courses, it all depends on what you want to achieve from your car and caravan weighing.