phase measurement using lock in amplifier

[ikki91chan]

I'm Azura. I'm doing research about thermal wave physics. my project require two thermal image using the labview, daq and lock-in amplifier. first image is require the voltage value which i receive from daq. second image is require phase value receive from lock-in amplifier. but currently, I'm having problem to receive the phase value and form image from the phase value.I'm only get 0 reading for phase using lock in amplifier. is it have another way to receive phase data using usb daq? I'm using lock in amplifier model sr530. Here I am attach labview for lock in amplifier, SR530.

[cbutcher]

Am I right in thinking that:

• You want to calculate the phase of a signal using the method described in the SR530 manual, Ø = - tan-1(Vpsd2/ Vpsd1)
• You have used the VI you attached to communicate with the SR530 but you received results of "0" for all of the outputs (Ch1, Ch2, X1, Freq)?
• You already configured the jumper switches in SW2 to match the settings you have on the VI (which I can't find, but might have something to do with the global variable 'VISA Aliases'?

It's not clear to me where your termination character is set, or what the default for the SR530 is. You can apparently set custom termination character(s) (up to 4) using the 'J' command, but I'm guessing that either <LF> or <CR><LF> are the default, which is likely to be the default for LabVIEW too.

You might have an easier time using the VISA Configure Serial Port node and holding onto your VISA value - your current VI seems to be indexing an array of existing VISA connections, which although it probably (possibly?) works isn't the clearest implementation.

[ikki91chan]

yes, I want phase of a signal using the method described in the SR530 manual, Ø = - tan-1(Vpsd2/ Vpsd1).I only get the 0 for the ch.2 .but  I receive the reading for Ch,1, X1 and  frequency.

[cbutcher]

When you set the display to R,Theta and read Ch2, you should read the phase - is this right?

But this doesn't display anything for you?

[ikki91chan]

yes, I set the display to R, Theta. I should read the phase in Ch.2 but this doesn't display anything. It's only display for Ch.1 and frequency reading.

[cbutcher]

If you set the display type to x,y (type 0) do you get a response from Ch2?

[cbutcher]

I'm going to try and create a different VI (with a different style/method) that you can try. Could you tell me the position of the jumper switches in SW2?

[cbutcher]

Attached is a project that I think should do the same as your code. Can you try it and see if it gets you a value from Ch.2? You might need to change the values in the 'Init' case (not) wired to VISA Configure Serial Port, if the jumper switches SW2 don't match the default LabVIEW settings.

[ikki91chan]

thank you but I cant open due to the labview version..I'm using labview 2015( 32bit).can you convert the version..so sorry

[cbutcher · Accepted solution]

No problem. This should open in 2015.