On-board scale

From Wikipedia, the free encyclopedia

For many types of trucks, knowing the loaded weight is important for operating safely and avoiding overweight fines. There are two ways that a driver can determine the approximate loaded weight - either by driving to an in-ground scale, or using on-board scales. On-board scales use either load cell technology or pressure readings from air suspension to calculate the weight on the vehicle axles.

The convenience of being able to weigh at the loading site is a key factor in the popularity of on-board scales. This ability eliminates the costs associated with using an in-ground scale, such as lost hours of service, scale fees, and driver wages.

Contents

[edit] Types

There are essentially four types of on-board scales currently in use:

[edit] Load cell scales

Load-cell scales are based on electronic load cell transducers, and can be mechanical or strain-gauge. There is a wide variety of scale types that can be built with load cell technology. Typically load cells are used in payload scales for vehicles with spring suspension.

[edit] Air-suspension PSI gauges

Air-suspension PSI gauges are used on commercial trucks and semi-trailers where accurate weights are not as critical.

[edit] Air-suspension load scales

Load scales for air-ride applications that show on-the-ground weight in pounds (LBS) or kilograms (KG) instead of standard PSI. These non-electric gauges are analog (dial-face) with versions that can calibrate for accuracy.

[edit] Electronic scales with PSI sensors

Electronic scales with PSI sensors measure temperature and pressure changes in a vehicle’s air suspension. It relays this data to a receiver hardwired into the cab, or wirelessly to a handheld unit, which interprets the data and displays an approximate axle weight or gross vehicle weight.

[edit] External links

There is a fifth type of on-board scale currently being used. It is a non-load cell scale, referred to as "pencil sensor" technology. This scale works on most types of mechanical, spring suspensions and can be combined with air ride suspensions as well.Accuracy with this scale is a weight descrepancy of 1% or less. This type of scale is manufactured by Cleral On-Board Scales.