System Calibration

General Principles

Any weighing device, whether it is a bathroom scale or a WIM system, must be calibrated at some time to relate the output from the device doing the measuring to some unit of weight. This is achieved by loading the platform with objects of known mass and recording the various outputs from equipment so that a mathematical relationship between the…
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Culway Calibration

Calibration Procedures It is recommended that Culway calibrations are carried out at least once every two years as well as after each major repair or changes to the pavement and changes/repairs in the vicinity of the sensors. Replacement of any strain gauges also requires a re-calibration. The calibration process requires the collection of controlled vehicle axle mass data, analysing and…
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Bending Plate Calibration

Calibration Techniques Bending plate WIM calibrations are to be carried out at least once annually as well as after each major repair or adjustment at the bending plates e.g. reinstallation of one or several frames, height adjustment and pavement changes/repairs in the vicinity of the sensors). Replacement of a bolt or fastening of rails does not require a recalibration. There…
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Capacitance WIM Calibration

Mikros-2005b recommends the following method for calibration and verification of HSWIM capacitance pad installations. Ideally, a two-axle truck with high quality suspension (air suspension preferred) should be used for calibration and verification. Alternatively more than one calibration truck can be used. The same procedure must be followed as with one truck. The detailed data capture and analysis procedures are part…
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Piezoelectric WIM Calibration

The calibration should not be performed within 72 hours of the installation of the sensors. It is recommended that calibration take place after two weeks of traffic having passed over the WIM site. The calibration procedure is dependent upon the end-users' requirements. It should clearly state the type of vehicles, the number of runs, the loads, the equipment to be…
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