A weighbridge is a valuable asset for any operation in the bulk transportation and logistics industry and many companies depend on the information gathered at this critical control point for a number of important things including resourcing, invoicing and cost control.
Accuracy and integrity is paramount for both the buyer and the seller and in many places, including Australia and New Zealand, weighbridges that are used for trade purposes have to be monitored and checked regularly to ensure optimum performance.
While a correctly calibrated weighbridge can be very precise mass measurement instruments; there are still some factors that can affect the accuracy of the weight measurement. If you’re considering investing in a weighbridge or want to understand more about your existing installation, it’s important to know about these factors and whether any of them may impact your system’s weighing accuracy.
They can be categorised into five main sectors namely mechanical, environmental, vehicle, human and system-related. It’s worth discussing the issues with a reputable and experienced weighbridge supplier who will take all of these factors into consideration when recommending the best weighing system for your particular application.
All weighbridges operate with load cells. Quality of the equipment is paramount, as is regular checking and calibration to prevent mechanical variation errors and to ensure precision measurements and testing repeatability.
Temperature changes alter the sensitivity of the load cells, and this can affect outputs. If your weighbridge is to be installed in an area where there are significant variations in temperature, you should discuss how you can mitigate the effects of this with your weighbridge supplier. Other environmental factors that can affect weighbridge accuracy include high and cross winds, humidity, vibration, a build-up of dirt, moisture and corrosion.
If the weighbridge uses stored data on empty vehicles to calculate the payload, then the readings will be affected by variables such as the fuel level of the truck, spare tyres, accessories (for example chains and tool boxes), the length of the truck and the weight of the driver. Accuracy can also be compromised if the weighing system is subjected to a sudden, heavy load, such as when a load is dropped onto it or if the platform is knocked or disturbed. Recalibration may then be necessary.
Human error is always a consideration, and can arise through supply of incorrect information by the driver of the vehicle or input by the bridge operator.
System errors can occur if there is interference with the electronic signal transmission (which can be caused by radio frequency interference, electromechanical interference, moisture and temperature) or if there are problems with the actual instrumentation and control devices.
For optimum accuracy, it is imperative to take into consideration all factors that can affect the weighing system. The effect of these variables can be minimised by choosing a well-designed and high quality weighing system that is suited to your specific application and then ensuring that it is operated and maintained to the highest standards.
AccuWeigh is the largest provider of weighbridge services in Australia and has over 1 000 weighbridge installations to their credit. The team comprises highly experienced and well-regarded professionals who take every aspect of weighing equipment seriously, from designing solutions to meet customer’s needs, installation and maintenance, weighbridge repairs and weighbridge calibration. AccuWeigh has skilled weighbridge crews and weighbridge test trucks conveniently located in all mainland states. Contact your nearest branch to discuss your requirements.