Data Acquisition

[scott christensen]

Andris,

This place sells PC data acquisition boards about as cheap as anybody:

  http://www.advantech.com/

But you will need several cards (and they add up $$$):

  PCL-711    DAS card to go in PC  (or the 812PG is good too)
  PCLD-774   board for external connections  (regular sensors)
  PCLD-779   amp board with isolation (thermocouple conditioning)

Thermocouples open a can of worms.  These suckers have very very small 
voltages that need externally amplified for generic PC A-to-D cards to 
handle.

Additionally if you do not get an amp board that electrically isolates each 
thermocouple from each other (i.e. stay away from "single ended" types), 
then if you connect the thermocouples' tips together electrically (by 
touching multiple tips to the same conductor, the engine in this case) then 
it will "short out" and your system won't work.  Been there done that.

Might be cheaper to buy an external "box" designed for reading thermocouples 
and reports the temps back to the PC via a serial port.  I've seen them 
advertized in the back of electronic magazines.

Good luck.

-scott

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