Pin load cells are used to measure applied weight in the central part of the transducer (G area) in comparison to the two extremities of the load cells (E area).
The body of the load cell is realized with rectified cylindrical surface to allow the installation of the running gear in the central part. It guarantees that the transducers are bound to the two extremities, maintaining measuring axis correctly oriented on the axis of the force that should be measured.
These load cells are designed for difficult industrial use and environments, where safety is fundamental. The safe factor changes according to the model and can reach 200% against mechanical overloads, for static or almost static loads.
The transducers are designed thanks to FEA analysis, in order to have the best working geometry. The body of the load cell can be realized in high resistance steel or 17-4 PH stainless steel, according to the need of the customer and of the application.
There are different versions of the transducers:
MD transducers have a typical sensitivity of 1 mV/V and they are available with built-in electronics, with analog or digital output.
Each transducer is provided with individual test certificate, showing the measuring characteristics. These values are obtained comparing the transducer to an internal reference sensor or to a SIT sensor, according to the request of the customer.
Transducers with analog built-in amplifier are adjusted in order to combine signal references and measuring ranges of the transducer. Digital transducers provide measure in engineering units and with the calibration resolution.
Different measuring functions are available:
Main characteristics of the digital amplifiers are:
|Temperature effect on zero (within 5°K)|
< ±0,1 % FS
< ±0,15 % FS, within 4 test hours at FS
|Return to zero from full load|
< ±0,07% FS after 30 minutes at FS
from -10 to +40°C compensated
Analog outputs: 1mV/V (typ.), ±5V, ±10V, 4-20mA (2 wires) with zero and gain settings
– RS485 and RS422 (Protocols: DSEbus, Modbus).
– CAN (protocol CAN Open, DSP406 profile).
Environmental protection: IP65.
Force is applied onto the central section of series MD5000 pin load cells (see size “G” of technical bulletin) and the reaction force is on the side sections (see sizes “E” of technical bulletin).
Series MD5000 load have been designed for heavy duty applications where safety is a must (there is a safety margin of 200%FS and a rupture limit of 500% FS).
The extreme ruggedness is obtained by using a body in solid rod that increases the flexional strength of the central section and the shear strength on the lateral cavities.
Series MD5000 are available as “S” (= standard) version and as “L” (= Long) version where the central “G” longness size can be as long as required by customers provided that the unitary strain does not exceed 20-25Kg/mm2
The MD5000 series can have a CE marked built-in electronics
The digital electronics has an high resolution 24bit A/D converter and allows a long distance data transmission protected against electrical noise.
The digital electronics with RS485 and RS422 outputs (DSEbus and Modbus protocols) allows the following functions: calibration and data transmission in engineering units (kg, tons, daN etc.), dynamic zero, digital filter (sampling rate from 7,5 up to 960 Hz), high accuracy (up to 10 linearization points) and an easy service (overload events memory).
Software: It is provided free of charge, with RS485 and RS422 outputs (DSEbus and Modbus protocols), also a software to be installed into the user’s computer (not included) that allows an easy setting of the electronics working parameters and a data visualization.
The load cell has a built in calibration circuitry whenever it has the 1mV/V not amplified output.
A calibration certificate is provide together with every unit.
The load cell is well protected against dirt by means of siliconic sealants and rubbers allowing an IP65 rating.