Can precision scales be operated on batteries? How can they be used in a mobile setting?
If, however, the application will allow the use of automotive type lead acid batteries, or large Lithium Ion automotive type batteries, the solution becomes fairly simple and straight forward. The battery output is used to drive an inverter that produces a pseudo sine wave output at 115vac rms. From there on just plug in the wall transformer that comes with the scale and your power problems are solved. However, mobile settings for precision scales have other problems. One of the biggest is re-leveling the scale at every new location. Another can be the amount of vibration caused by the vehicle’s suspension with human activity. If changes in elevation are encountered from stop to stop the scale must be re-calibrated to compensate for the change in the gravitational force. The changing temperature inside a vehicle can also require frequent recalibration. Automatic internal calibration can be a big help in this situation. The vibration problem can at least be partially, if not completely, overcome by allowing the scale to integrate the weighing result over a longer period of time. Generally speaking an integration time of 10 seconds will eliminate the effects of mid size truck suspensions. Build it into your planning.
If your application will allow the use of a scale with an accuracy of 0.03% you can use an Industrial Scale, not usually defined as a precision scale, but this gets you to strain gauge technology and cuts the power requirement by roughly a factor of 100. Now portable scales are easily found that operate on conventional type portable batteries. The other problems remain but are not nearly as severe when the accuracy requirement is reduced by a factor of 15.
In the end we offered a solution to mobility for high accuracy measurements, but not within the precision scale itself. Where lower accuracy is tolerable in the application an Industrial scale is an excellent solution. Remember the gravity and temperature problems, and plan on increased integration time (like in live animal weighing) being required. Happy travels. . .