Refuse-collection vehicle with DIGI SENS weighing system
The principle that the producer pays is being applied more and more to waste disposal. The determination of the weight is much fairer for the waste producer than invoicing based on volume. For this reason most refuse-collection vehicles today are equipped with scales. The distinction must be made between on-board weighing systems and catch-weighers. DIGI SENS offers both solutions in different variants. The on-board weighing system, which measures the total vehicle payload, is suited above all for invoicing whole districts or large industrial customers. The inherent limited resolution of 10 kg, or at the very best 5 kg without wind and in dry conditions, means that it is hardly suitable for invoicing individual waste containers. For this latter application, the catch-weigher is to be recommended. Even the catch-weighers are divided into two categories, static and dynamic. In the static version, the tipping must be stopped to measure in turn gross then tare weights. In the dynamic version, the weight measurements are carried out in motion, without interrupting the tipping process.
On-Board Weighing System on a suction vehicle
The DIGI SENS dynamic catch-weigher consists essentially of three different components:
- The guide-plate load cell type SO or CE, with oscillating-wire sensor. These cells, with OIML R60 approval, exist in various versions for different nominal loads. According to the tipping method, one or two of them are used per installation.
- 1 or 2 type BB accelerometers are used to compensate vehicle tilt and dynamic acceleration forces. These should be mounted as near as possible to the centre of gravity of the waste container to be weighed or the lifting arms.
- The METIRON data processing computer uses a special algorithm to calculate the gross and tare weights from the load cell and accelerometer signals, subtracts one from the other and labels the resulting net weight with time and date, identification number, possibly also position data (GPS), then stores the result . The METIRON computer communicates via serial interfaces with the container identification system, on- board computer, printer and other peripherals. It also has various digital inputs and outputs for switches, etc. It can be further completed with the METERM display unit. In the absence of an on-board computer this acts as the control unit, with display, keyboard and RAM-drive.
- The catch-weighing software POLYPHAG forms part of the METIRON computer. Thanks to many years of practical experience, this has been developed to perfection and can thus be configured for all sorts of applications and interfaces. The availability of faultfinding, set-up and calibration routines make POLYPHAG very user-friendly. In addition to these key components, DIGI SENS can also offer all other system accessories, such as identification system, printers, memory-card drivers, power supplies, cables etc.
Refuse-collection lorries with DIGI SENS weighing system