Wednesday, May 21, 2014

Hense Wägetechnik launched a New Intelligent Junction Box for Load Cells



Hense Wägetechnik GmbH (Germany) - A weighing system is still consisting of one or more loading assemblies, a junction box for signal summing and an electronic unit to display the weight value and transfer the weight information to the PLC system. Hense Wägetechnik GmbH offers a comprehensive telephone support and provides field startup on demand. The Hense service engineers figured out, that a number of typical installation errors are always repeating in the praxis:

  • False connection of the 4 - 6 wires between the load cells and the junction box
  • The Load Cells are out of balance
  • Cable break or bad connection at the terminals
In the praxis service engineers often ask the customer to measure the single load cell signals with a multimeter (voltage meter). For this reason it is necessary to disconnect the load cells and measure the excitation voltage and the individual mV signals of each load cell. Under the line this is a very time consuming process.



To solve this problem in the future, Hense Wägetechnik developed a “smart“ solution called the “intelligent junction box”.

The intelligent junction box is powered via the load cell amplifier and does not require a separate supply voltage. For this reason the intelligent junction box can be used in place of a standard junction box. The following parameter are continuously monitored and display:
  • Over- and underload of load cell signals (adjustable)
  • Cable break and contact faults
  • Excitation voltage to load cells
  • Load deviation on load cells
The bright OLED graphical display show system errors and fault conditions with the facility to view individual load cell outputs, average load cell outputs and excitation voltage. A “healthy” voltage free relay contact is available for external connections. All fault messages are transmitted via the on board CAN bus interface.

The Display shows the actual conditions of the weighing system:



The load cell signal can be transferred via conventional 4 or 6 wire connection to the amplifier. Alternative a save 2-wire CAN bus connection can be used for a distance of 200m and more. If more than 4 load cells or one silo should be monitored, the CAN bus allows to establish a 2 - wire network.

To complete the system, Hense Wägetechnik GmbH offers a high precision load cell amplifier, which is able to communicate with the “intelligent“ junction box.



The load cell Amplifier „Target 260” receives the CAN bus information and shows the weight and fault information in the bright display. Errors are stored in the memory of the intelligent junction box and the “Target 260” electronic.

This diagnostic function helps to isolate the source of the error with a short time period. The “Target 260” amplifier can be supplied for wall or table, panel or DIN - rail mounting. A stainless steel enclosure is available as an option.



The following output signals are available: 0(4) - 20mA / 0 - 10V / 0 - 5V / 3 voltage free relay contacts / USB interface or serial interface RS 232.

Optional interface: Profibus DP and Profinet.

For more information about the New Intelligent Junction Box for Load Cells from Hense Wägetechnik click here.


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