Industrial :
Industrial machine service hints , if machine is dead or unexpected has a malfunction .
Industrial Programmable Controllers : PLC / analog multiplexer add on / schematics
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2 x 16 ch . analog multiplexer and 1 x 1bit expander make a 32 ch. analog multiplexer.
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4 - 20 mA current loop .
Interresting examples: AD693 and AD694 from Analog Devices.
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