Hello,
I am a first time user of arduino. I want to connect the arduino device to my Labview program in order to produce a 4-20 mA signal. This in turn will be used to control a valve. Any suggestion as to what Arduino product and shield should I buy. Thank you
Uno.
I don't know what shield has a chip that does a 4-20mA driver.
Try google?
There is an outfit in Santiago that makes a 4-20mA shield for some breathtaking price. I think it is called MCI. I understand all you need is shown below, which is the sort of thing that could go on a prototyping board that then connects to a Uno. Freetronics make a version of the Uno that has a proto area included, but they are probably more expensive.
Monnoo:
in order to produce a 4-20 mA signal. This in turn will be used to control a valve
What sort of resolution do you need on the output current, and how accurately do you need to control the current?
I'm wondering whether you might be able to get away with a crude DAC made with a resistor ladder, or maybe just a set of I/O pins each with a fixed resistor to act as a current limiter, so you could just turn on the I/O pin corresponding to the current you want.
Uno. I don't know what shield has a chip that does a 4-20mA driver. Try google?
I didn't know that Newbies knew what Google was. Was there like an announcement on TV or something ? They mostly seem oblivious of it's existence, as far as I can tell.
Could add a few parts to this prototype shield:
http://wwww.crossroadsfencing.com/BobuinoRev17/
I have one of those. Very convenient.
