Last update : 06. July 2010

5 * 4...20 mA Converter Interface
 Interface for up to 5 * 4..20 mA sensors. Can be  integrated in a logger  system or may work selfconatined.
 Schnittstelle für bis zu 5 * 4...20 mA Sensoren. In ein Loggersystem  integrierbar oder freilaufend nutzbar.
                   b1      bild2

 (click to the pictures)

The 4...20 mA converter interface project is a part of a heating logger system for a Groundwater Heat-pump. It allows to display and log current temperatures, consumed AC power, generated Heating power, the water level and water temperature of the groundwater wells, pressure in the groundwater pipes and some other important informations. The  4... 20 mA converter is basically supposed to be used for the well controlling, but can be used for any sensor which provides a 4 ... 20 mA interface.

Depending on the  DIP-switch and some jumpers, the 4 ... 20 mA Converter can either be read out self-contained via a standard RS232 connection or on request by a host via a  serial (TTL) data stream, similar to RS232. There is a document which describes the request and answer structure.

b3       b4

                     (click to the pictures)

In this particular case, there are 5 sensors connected to the converter. There area two water  level sensors  (based on pressure sensors) , two PT100 temperature sensors and a single pipe pressure sensor .

b5      b6     b7             

 (click to the pictures)

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