Thermocouple VI

[CB1]

I need a VI that takes the voltage/temperature from a thermocouple and in turn controls the on/off switch of a heater.  Basically the heater will return a fluid to its original temperature after being altered. Thanks in advance.

[EdDickens]

You probably already have what you need by using a combination of Examples that ship with LabVIEW.

Look for one that reads a thermocouple and for one that controls a digital line (if that's what you're switching). Then add the digital code to the thermocouple code and switch the line when the temperature goes above/below what's being read.

Have a shot at this and let us know how you make out.

Ed

[mfitzsimons]

In LabVIEW use Help -> Find Example and then select search tab and search for Temperature.  There are many good examples there how to take and display temperature.

Matt

[CB1]

Okay guys I have found the appropriate thermocouple VI to feed the temperature into LabView, but I see a few different switch VI's to link to it...the relay switch looked most appropriate, but still didn't look correct.  Any ideas?

Thanks

[mfitzsimons]

What are you using to control the switch?  Digital I/O?

[CB1]

Correct

[Dennis_Knutson]

If you're talking about the Express VI called Relay, you're looking at the wrong example. This function does not control any hardware. It is used to connect/disconnect a signal in software on or off. You need to look at the hardware examples and what you use depends on what hardware you have. For example, you can use a digital signal from DAQ board to control a relay. I'm assuming that you have an NI DAQ board to measure the temperature and most have at least 1 digital port. Look at the Hardware Input and Output>DAQmx>Digital Generation examples. You should also know that the current and/or voltage capability of a digital line is often not enough to directly turn on a relay. You may need a driver between the digital output and the relay coil.

[mfitzsimons]

Search examples for digital.  There are a bunch of Digital I/O examples that start with: ""Write to 1 Dig Line (xxxx)" where xxxx is the product model number you are using.

Matt

[mfitzsimons]

Reposting response, somehow my answer got posted before the question:

Search examples for digital.  There are a bunch of Digital I/O examples that start with: ""Write to 1 Dig Line (xxxx)" where xxxx is the product model number you are using.

Matt