There are many circumstances where an onboard scale benefits the operator even when stationary scales are present. “For example, when loading in a pit that has an in-ground scale, but not at the loader, you maximize your payload prior to reaching the scale, avoiding a situation where you have to get back in line to top up or go back and dump some out due to an overweight event,” says Panagapko. “Operators can increase the number of loads in a day and increase the per trip payload with an onboard scale that computes the weight right at the loading area.”
It is just as important to get the load distribution correct. “Onboard scales have the ability to provide axle group weights, as well as the total vehicle weight,” notes Riley. “Therefore, the axle groups weights can be used to assist in load distribution.”
It usually does not take long for the onboard scale to pay for itself. “ROI is variable between applications,” says Riley. “It is usually reached in a time frame that justifies the allocation — sometimes in as little as a few weeks.”
Systems vary in cost and features. “A typical cost to scale an over-the-road dump truck is roughly $4,000,” says Housley. “Contractors realize their return on investment by maximizing payloads no matter what they load, eliminating out of route travel to jump scales.”
“Our TruckWeight Smart Scale ranges from $900 to $2,400 to outfit a commercial rig with mechanical or air suspension,” says Panagapko. “Operators who are paid by the ton realize a return on investment in less than three months for most operations. If they are paid by the mile, the return on investment is less than one year for most operations.”
Coordination with loading tool
Careful communication between the truck driver and loading tool operator yields maximum payloads with minimum effort. For instance, the loading operators know Adventure Trucking has these systems on board. The drivers will use CB radios and hand signals to increase loading efficiency.
“They know to watch us,” says Chandler. “We hold up one finger for 1,000 lbs. or three fingers for 3,000 lbs. If the loader operators are close, within a few thousand pounds, then they slow down quite a bit.” And if the truck gets slightly overloaded, the driver doesn’t have to drive to the scale to find out. “We just back up to the pile and trickle a little bit off.”
Some systems allow the loader operator to carefully monitor the load. Housley reports the LoadMan allows the loader operator to easily assess the load on a given truck. “After getting the first shovel/bucket load, they raise their dump bed to the weighing position, then with each additional scoop, it takes 2 to 3 seconds for the LoadMan system to display the added weight by axle groups. These weights can be displayed in the cab, on a large scoreboard display or even on a remote Android smartphone.”
Other manufacturers offer similar devices. “SI Onboard offers a hand-held remote display for the loading operator to monitor the weight distribution in the vehicle being loaded,” says Riley.
Vulcan On-Board Scales also offers a monitor for the loader operator. “The person running the loader can monitor the amount of material being loaded through a wireless hand-held device, which displays the same weight data as the display in the truck,” says Elefson.
Increased Accuracy Pays
Do some research and understand what is available before purchase. “Some units only provide load weight, while others offer per axle weight,” says Panagapko. “Our wireless Smart Scale gives the operator per axle weights.”
After Adventure Trucking sets up critical truck parameters in its LoadMan systems, it can track all critical load information. “It tells you what the steer axle weighs,” says Chandler. It tells you what the drive axles weigh. “It tells you what your gross weight is. It tells you what your trailer weighs. It tells you everything that you want to know. I think we are within 1% to 2% accuracy.”
Don’t forget to leave a safety margin to prevent overloading. “A safety margin should be factored in to ensure that the maximum legal payload is not exceeded,” says Panagapko. “Scales range in accuracy from 0.3% up to 3% depending on the loading environment.”
Elefson adds, “A load cell-based on-board scale system measures typically within 1% of GVW, and often better than that. The more accurate the system, the less weight you have to allow for a safety margin. The safety margin depends on what leeway is allowed in a particular application. However, always aiming at 1% under is a safe loading target to stay legal.