Celmi Team has participated in the working group of CANopen foundation to define the protocol for on-board weighing devices. The standardized interface allows an easy integration in the networks of fitters based on CANopen. These systems are usually installed on commercial lorries (e.g. waste collection vehicles), construction machines (e.g. excavators), agricultural and forestry vehicles and special off-road vehicles (e.g. for airports). Typical applications include bulk transport, waste management, quarries and logging.
The specification of CiA 459 profile consists of three parts. The 1st part contains a general description and provides a functional overview. The 2nd part indicates communication parameters and the 3rd part standardizes application parameters. An on-board weighing device, in accordance with this specification, collects the values of the sensors of load cells, processes them and provides weighing data to CANopen interface for further evaluations, registrations and for overload protection systems. This device can monitor the load, measure the weight of axles and process weighing values.
A specific example for the application of this device is the double shear beam load cell, DSB type, designed and realized by Celmi srl for the sector of waste dynamic weighing on lorries. It is completely made of stainless steel, welded with microplasma, and our technicians are able to study it according to the specific needs of our customers: both with 4-20 mA and CANopen CiA 301 output. Here are some technical characteristics of this product:
METROLOGICAL CHARACTERISTICS
- COMBINED ERROR Fcomb ±%Ln 0,075
- RATED LOAD Ln t 10/15/20/25
- MINIMUM LOAD Lp %Ln 5
- MAXIMUM LOAD Ll %Ln 260
- LINEARITY Flin ±%Ln 0,05
- HYSTERESIS Fu ±%Ln 0,04
- REPEATABILITY Fv ±%Ln 0,03
- DRIFT UNDER LOAD IN 30′ Fcr ±%Ln 0,05
- RATED TEMPERATURE RANGE Btn °C -10+85
- THERMAL VARIATION OF ZERO (-10+40°C) TK0 ±%Cn 0,1
- THERMAL VARIATION OF THE OUTPUT (-10+40°C) TKC ±%Cn 0,06
- THERMAL GRADIENT °K/h <5
ELECTRICAL CHARACTERISTICS
- RATED OUTPUT Cn mV/V 2
- RATED OUTPUT TOLERANCE Dc ±%Ln 0,1
- RATED SUPPLY VOLTAGE Bsu V 5÷24
- MAXIMUM SUPPLY VOLTAGE Usmax V 30
- INPUT RESISTANCE Re W 800±10%
- OUTPUT RESISTANCE Ra W 700±1%
- ISOLATION RESISTANCE @ 20V Ris MW >2000
- ZERO LOAD OUTPUT TOLERANCE Do ±%Cn 1
MECHANICAL CHARACTERISTICS
- ULTIMATE TENSILE STRENGTH Ld %Ln >300
- TRANSVERSE LOAD Llq %Ln >130
- DEFLECTION hn mm <0.3
ENVIRONMENTAL CONDITIONS
- OPERATING TEMPERATURE RANGE Btn °C -10+80
- STORAGE TEMPERATURE RANGE Bts °C -40+85
- PROTECTION DEGREE IP-67