On-board scale
On-board scales are mobile weighing systems that have been integrated into a vehicle, such as a flatbed truck or semi-trailer.[1] In the United States, such scales are used primarily as a self-check for weight compliance. Thus the operator can use the scale to determine the weight of the vehicle as it is loaded.[2] This enables the operator to avoid penalties by complying with state weight laws, while still transporting the maximum allowable weight. Weight laws are based on safety considerations; in the United States, the Federal Highway Administration requires each state to certify its enforcement of weight laws.[3] In addition, some states allow on-board scales approved under the National Type Evaluation Program (NTEP) to be considered legal for trade.[1]
The convenience of being able to weigh at the loading site is a key factor in the acceptance of on-board scales. This ability eliminates the costs associated with using an in-ground scale, including lost hours of service, scale fees, and driver wages. Additionally, operating a vehicle or a truck fleet at optimal payloads ensures minimizing running costs while maximizing profit.
On-board scales sometimes appear in non-commercial applications. In one such, the Federal Motor Carrier Safety Administration used an on-board scale in 2009 on a technology demonstration vehicle.[4] The scale was one among several systems intended to provide information for researchers developing tools to determine the safety fitness of a vehicle.[5] Considering an unrelated possible non-commercial application, in 2015 the Federal Highway Administration wrote: "Recording and collecting data from on-board load cells can provide a metric for [weight law] compliance."[6]
History
[edit]On-board scales have been used on vocational trucksa at least since 1985. Among the first industries to use these scales were logging operations, in which the difficulty of determining the weight of newly cut logs, with their varying density and moisture content, was problematic. Avoiding overweight tickets by weighing when loading the logs was the incentive for using these scales. As more states began more rigorously enforcing weight limits in the early 1990's, other vocational trucking industries, such as waste hauling and aggregate hauling, began to install on-board scales.[7]
A few years later, "A Vehicle Mounted Load Indicator System" received a US Patent in 1989. This system was based on the air pressure in a truck's air suspension. It relied on calibration and claimed an accurate reading of the weight of the carried load, transmitted to a readout.[8] On-board scales using the technology described in this patent were first sold in 1991.About Air-Weigh
Types
[edit]Load-cell scales
[edit]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.
Air-suspension PSI gauges
[edit]Air-suspension PSI gauges are used on commercial trucks and semi-trailers where accurate weights are not as critical.
Air-suspension load scales
[edit]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.
Electronic scales with PSI sensors
[edit]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.
Low Cost Bluetooth Truck Scales
Heavy Duty Bluetooth Truck Scales
Notes
[edit]- ^a Vocational trucks are designed for a specific task, such as collecting refuse, mixing and pouring concrete, firefighting and the like. Each is custom-built on a truck chassis and may be light-, medium-, or heavy-duty.[9]
References
[edit]- ^ a b "On-Board Weighing Systems" (PDF). Bureau of Weights and Measures. Wisconsin Department of Agriculture, Trade and Consumer Protection. Retrieved 20 November 2024.
- ^ "Comprehensive Truck Size and Weight Limits Study - Compliance Comparative Analysis Technical Report". Freight Management and Operations. Federal Highway Administration. Retrieved 20 November 2024.
- ^ "State Information on Citation and Civil Assessments Issued for Overweight Violations". Freight Management and Operations. Federal Highway Administration. Retrieved 21 November 2024.
- ^ "Technology in Motion Vehicle Upfitted for Role as Outreach Tool" (PDF). Technology Corridor News (#4). Federal Motor Carrier Safety Administration Office of Analysis, Research, and Technology. October 2009. Retrieved 25 November 2024.
- ^ "FMCSA Shows Off New CMV Inspection Technologies". OHS Online. Oct 18, 2010. Retrieved 25 November 2024.
- ^ "Appendix B. Summary of Data Gathered from International Experts on Truck Size and Weight Enforcement". Comprehensive Truck Size and Weight Limits Study (PDF). U. S. Department of Transportation Federal Highway Administration. June 2015.
- ^ McCurry, Jerry (October 3, 2016). "Trends in On-board Scale Systems for the Waste Industry". Waste Advantage. Retrieved 24 November 2024.
- ^ United States 4,832,141, Richard L. Perini & James O. O'Dea, "Vehicle Mounted Load Indicator System", published May 23, 1989, assigned to Accu-Weigh Systems,Inc.
- ^ "What is a Vocational Truck? Clearing Up the Misperceptions". CFF. Commercial Fleet Financing. Retrieved 24 November 2024.