An accurate scale is an essential tool for any company whose revenues are based on the weight of goods entering or exiting a facility. Without scale accuracy a company can lose thousands, if not hundreds of thousands of dollars annually. On the other side of the equation, annual maintenance costs for a truck scale run anywhere from $1,000 to $3,000. If one compares that to the potential cost of weighing errors, most users find that a good scale maintenance program more than pays for itself; oftentimes it also pays for the actual cost of the scale.
To be most effective, a scale maintenance program must have five key components: use of a state-licensed service provider; conducting calibration using state-certified test weights with written calibration and test report for proof of accuracy; a thorough testing process; visual inspection services and minor repairs; and thorough reporting. Here’s my take on the key aspect of each component.
Use a state licensed service provider
A commercial scale company cannot certify a scale – only the state weights and measures organization can do that. But the commercial company has the authority to recalibrate and reinstate an inaccurate scale that has been “tagged-out” by the state, as long as the scale company is state-licensed and registered in good standing. So make sure the commercial scale company you are using shows you their valid license.
Use state-certified test weights for calibration
An established scale service company typically has its entire inventory of test weights tested and certified annually, in accordance with state weights and measures standards. Beware of service companies that test only a portion of their overall weight inventory each year.
Make sure testing process is thorough
The test should start by determining the length of the platform and the total number of sections along that length. (A scale section is where there is a load point, also called a load cell or strain gauge). Load points are where weight is transferred from the load to the scale and where scale accuracy is maintained. It is critical that the accuracy of each load points is maintained, so as weight is applied, it is transferred evenly. If a load point or section fails a strain test, then it must be calibrated to conform to requirements by making a mechanical or electronic adjustment.
Incorporate visual inspection and repairs
A thorough scale maintenance program must include regular visual inspection, followed by any necessary repairs of issues found. The visual inspection should include scale condition, regulatory conformance, signs of damage and debris buildup, safety, clearance, corrosion, and any electrical conditions. A good service company should conduct a free visual inspection be able to perform any minor repairs while on-site for the maintenance visit.
Every maintenance inspection should include a written report documenting test results, and including both before and after calibration, as well as a summary of finding and recommendations.