Weighbridge Manufacturers

For legal enforcement purposes, it is mandatory that the personnel involved in the weighbridge operations are legally authorized to do so. It is also critical that personnel involved in weighbridge operations are properly trained and are able to carry out the weighing procedures in the prescribed manner, particularly in those countries where overloading is treated as a criminal offense. Certain of the weighbridge operational procedures depend on the type of weighbridge being used while others are mandatory to all facilities. It would be normal for any weighbridge facility to have a Weighbridge Operators Manual to ensure that all operational procedures are carried out in a proper and consistent manner in accordance with the manufacturer’s requirements. Failure to adhere to proper weighbridge operational procedures could result in an overloading violation being thrown out in court.

The efficient and effective control of overloading utilizing increasingly sophisticated equipment requires well-trained and experienced staff conversant with a wide range of related disciplines including the following:

• Transport environment
• Legislation and regulations
• Weighbridge equipment
• Weighing operations
• Software operation
• Data management
• Management reporting
• Staff management;
• Operations management
• Maintenance management and
• Safety.

Thus, it should be mandatory for all weighbridge personnel to follow a prescribed training course so that they are able to perform their duties satisfactorily in terms of ensuring that the applicable weighing procedures are followed and overload control regulations are applied correctly. In a regional context, training should be carried out in a coordinated manner in order to endure uniformity across all countries.

1. It is advisable to weigh all vehicles without passengers or driver. If this is not possible or if the personnel refuse to leave the vehicle a note should be made to this effect with details of the number of persons on the vehicle. This note should be made on the ticket and on any other record. Whatever happens you should always be consistent with whether you weigh vehicles with the driver in or out of the vehicle.
2. It is important to be consistent as certain persons may wish to increase the GROSS weight of the load by addition of passengers and if and when the tare weight is taken without passengers the weight of the load appears heavier. Weighbridge Operators should take special care whilst passengers are on or in the vicinity of the plate.
3. Where practical the Weighbridge Operator should check the load for himself and if this is not possible the ticket should indicate the load as stated by the driver.
4. Weighbridge Operators should be aware that persons bringing loads to be weighed may conceal heavy items amongst the stated load. This heavy article can then be discarded and the goods delivered to a purchaser. e.g. Concrete blocks with scrap metal. The load is identified as scrap metal and following weighing the concrete is discarded and the scrap metal sold at the higher weight. Therefore the weighbridge ticket would be properly completed as ‘scrap metal/concrete’.
5. The Operator should always check any vehicle registration number for himself rather than rely on the driver.
6. The Weighbridge Operator should have a clear view of the plate and ensure the vehicle being weighed is positioned on the plate. Weighbridge Operators should be aware that persons requiring a weighing may deliberately leave a wheel over the edge of the plate to reduce the weight shown. This is either done to reduce the tare weight (and therefore increase the apparent weight of the load or to appear below the permitted legal weights for overloading purpose.
7. It is illegal to undertake a double weighing where that weighing will be used for a trade transaction. e.g. a load of hay for sale elsewhere.
8. Drivers sometimes require a weighing to ensure they are not overloaded on individual axles. It is permissible to undertake weighing of individual axles but the ticket and records should clearly indicate what type of weighing was carried out and which axles were weighed etc. The ticket should be endorsed – “Weights found are not for trade purpose”.

1. Regular checks should be made to ensure that there is clearance between the plate and its surrounding frame. If the weighing machine operates using a lever bottom work the plate should swing freely endways.
2. Regular checks should be made to ensure that the weighbridge is properly balanced when unloaded and the indicator shows zero. The Weighbridge Operator must know how to balance the weighing machine.
3. The balance of a weighbridge will be affected by the accumulation of dirt etc. on or around the plate. This should be regularly cleaned to avoid any excessive build-up.
4. Beneath the plate, levers or load cells may be affected by the build-up of dirt (sand) and should be cleared as necessary. If your weighbridge is prone to such contamination a regular maintenance programme should be implemented.
5. In a pit mounted weighbridge, balance and accuracy may be affected by a high water level in the pit which ‘floats’ the levers or the bottom work. In such circumstances pumping facilities should be available and the Weighbridge Operator will be expected to know how to use it.
6. The most common cause of ‘balance’ error is due to rain on the plate. During periods of rain the balance should be checked and adjusted more frequently and again as the plate dries.

The use of any weighing equipment used by the public, such as a weighbridge, is regulated by law. The principal legislation affecting the use of such equipment is normally contained in the Study for the Harmonization of Vehicle Overload Control. Under that legislation weighing equipment must be individually verified by an authorized Inspector with a stamp of verification and a certificate of verification issued by the inspector. In essence, the verification process basically involves placing standard weights that are calibrated and traceable to the national standard on the scale(s) and then confirming that the reading given is within the tolerance limits.

The frequency of verification is prescribed in the Act. Photograph Weighbridge Verification Failure to comply in all respects with the legal requirements of the Weights and Measures Act, including the verification procedures, would render weighbridge operations illegal. Calibration of a weighbridge is the carrying out of a set of prescribed operations which establish, under reported conditions, the relationship between the weighing system output and corresponding known values of the load applied to the weighbridge.

The calibration exercise is normally carried out by an accredited body in accordance with a prescribed procedure such as that contained in A Code of Practice for the Calibration of Industrial Process Weighing Systems, The result of the calibration is normally reported in a formal document – the certificate of calibration – which includes a variety of data deemed relevant by the calibrating authority.

The data obtained as a result of the calibration operation may be used to estimate the weighing system errors or to adjust the system output to an agreed-specified value.

The frequency of calibration is governed by the following factors:

• Manufacturer’s recommendation
• Frequency and manner of use
• Environmental influence and
• Accuracy sought