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.