Continuous voltage data acquisition with Agilent 34972A

[yehanxin]

Thank you for your reply. There is no meter beeps ,and the instrument did not show an“error". I have attached the picture of the instrument acquisition and the display of the front panel of the software. The sound produced by the instrument should be the sound of opening the channel, or the sound of the trigger opening. After all, I can collect data, but I can't set it up.

 following questions:

1.Now  I can collect 3 voltages data, but every time I collect it, the 34972 instrument will trigger once, it will make a sound, I wonder if I can trigger it once, then continue to collect a lot of points. Because I see other models of the instrument are equipped with multi-point acquisition module, as for 34972 I have not found this module, does it mean that it needs to be triggered once every time it is collected？

2. Although I can collect data now, I can't control the frequency of data collection, and I can't set the time interval for collecting data.

3. Every time I start collecting data, the display screen of the 34972 instrument will be locked. I can't see the date by pressing the"monitor"button. And the display screen is flashing "OPEN" and "VDC" all the time.

4. Also, every time I use the right mouse button to store waveform chart data, I can only store more than 1000. Can I increase the storage amount?

[RTSLVU]

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@yehanxin wrote:

Thank you for your reply. There is no meter beeps ,and the instrument did not show an“error". I have attached the picture of the instrument acquisition and the display of the front panel of the software. The sound produced by the instrument should be the sound of opening the channel, or the sound of the trigger opening. After all, I can collect data, but I can't set it up.

Answers in blue...

 following questions:

1.Now  I can collect 3 voltages data, but every time I collect it, the 34972 instrument will trigger once, it will make a sound, I wonder if I can trigger it once, then continue to collect a lot of points. Because I see other models of the instrument are equipped with multi-point acquisition module, as for 34972 I have not found this module, does it mean that it needs to be triggered once every time it is collected？

If it sounds like "click, click, click click, click click, click click, click click, click" when measuring multiple channels that is correct. What you are hearing is the multiplexer opening and closing relays as it measures each channel. Remember there is only one "meter" inside. So when measuring multiple channels the instrument still has to measure them one at a time.

In general you have to trigger a scan every time you want to take a measurement.

You can do a continuous measurement of  one channel at a time using the "Monitor" function. Just like pressing the "Mon" button on the front panel displays one channel, there is a VI in the Agilent driver that will basically do the same. But remember only one channel at a time.

This device is NOT a high speed DAQ, it's fastest  measuring speed is 200 channels a second. That equates to a maximum sampling frequency of about 200Hz, so it will not make a very good oscilloscope or be useful for any type of waveform display.

This device is intended to take a large number of different types of measurements at regular but relatively slow intervals. 

2. Although I can collect data now, I can't control the frequency of data collection, and I can't set the time interval for collecting data.

You make a timer in LabVIEW and trigger a scan when the timer runs out.

3. Every time I start collecting data, the display screen of the 34972 instrument will be locked. I can't see the date by pressing the"monitor"button. And the display screen is flashing "OPEN" and "VDC" all the time.

You must be using the "EZ Config" VI's. DONT USE THEM! Use the advanced configuration VI's like the examples I have posted, then the Monitor button will work.

Every single time you trigger a scan using the "EZ" vi's the instrument does this:

1. Turns on one channel
2. Configures the channel (mode, range, etc)
3. Measures that one channel
4. Turns off that channel
5. Moves on to the next channel and repeats

Using the advanced configuration VI's the channels are already configured, so every time you trigger a scan the instrument does this:

1. Measures every channel from lowest channel number to highest

4. Also, every time I use the right mouse button to store waveform chart data, I can only store more than 1000. Can I increase the storage amount?

Increase your chart history length. Also there are better ways to  save your chart data. You can just save the x and y data in a file and recreate the chart using Excel. 

[yehanxin]

Thank you for answering my questions. Your answers in blue, My new questions and answers are in red. 

 following questions:

1.Now  I can collect 3 voltages data, but every time I collect it, the 34972 instrument will trigger once, it will make a sound, I wonder if I can trigger it once, then continue to collect a lot of points. Because I see other models of the instrument are equipped with multi-point acquisition module, as for 34972 I have not found this module, does it mean that it needs to be triggered once every time it is collected？

If it sounds like "click, click, click click, click click, click click, click click, click" when measuring multiple channels that is correct. What you are hearing is the multiplexer opening and closing relays as it measures each channel. Remember there is only one "meter" inside. So when measuring multiple channels the instrument still has to measure them one at a time.

I did hear "click, click, click", so it was correct to collect three channels of data. Thank you for solving my problem.

In general you have to trigger a scan every time you want to take a measurement.

You can do a continuous measurement of  one channel at a time using the "Monitor" function. Just like pressing the "Mon" button on the front panel displays one channel, there is a VI in the Agilent driver that will basically do the same. But remember only one channel at a time.

I tried using the "Monitor" function, but I still can't continuously measure of one channel. Do you have a VI in this area? I want to refer to it. thank you!

This device is NOT a high speed DAQ, it's fastest  measuring speed is 200 channels a second. That equates to a maximum sampling frequency of about 200Hz, so it will not make a very good oscilloscope or be useful for any type of waveform display.

This device is intended to take a large number of different types of measurements at regular but relatively slow intervals. 

2. Although I can collect data now, I can't control the frequency of data collection, and I can't set the time interval for collecting data.

You make a timer in LabVIEW and trigger a scan when the timer runs out.

 I have solved the problem according to your method.

3. Every time I start collecting data, the display screen of the 34972 instrument will be locked. I can't see the date by pressing the"monitor"button. And the display screen is flashing "OPEN" and "VDC" all the time.

You must be using the "EZ Config" VI's. DONT USE THEM! Use the advanced configuration VI's like the examples I have posted, then the Monitor button will work.

I did use advanced configuration, I've attached pictures of the basic functions I used.  Is it because I didn't write the" Monitor "function?

Every single time you trigger a scan using the "EZ" vi's the instrument does this:

1. Turns on one channel
2. Configures the channel (mode, range, etc)
3. Measures that one channel
4. Turns off that channel
5. Moves on to the next channel and repeats

Using the advanced configuration VI's the channels are already configured, so every time you trigger a scan the instrument does this:

1. Measures every channel from lowest channel number to highest

4. Also, every time I use the right mouse button to store waveform chart data, I can only store more than 1000. Can I increase the storage amount?

Increase your chart history length. Also there are better ways to  save your chart data. You can just save the x and y data in a file and recreate the chart using Excel. 

Increase  chart history length does solve the problem. thank you! I tried the second method you mentioned, but I didn't succeed. I used waveform chart, and I couldn't store all the data into the table in real time. Is there any VI in this aspect that I can refer to?

[RTSLVU]

---

@yehanxin wrote:

You can do a continuous measurement of  one channel at a time using the "Monitor" function. Just like pressing the "Mon" button on the front panel displays one channel, there is a VI in the Agilent driver that will basically do the same. But remember only one channel at a time.

I tried using the "Monitor" function, but I still can't continuously measure of one channel. Do you have a VI in this area? I want to refer to it. thank you!

In the 3497x pallet you will find this VI, it will continuously measure one channel. 

    

But that channel has to be fully configured using the advanced configuration VI's first

Increase  chart history length does solve the problem. thank you! I tried the second method you mentioned, but I didn't succeed. I used waveform chart, and I couldn't store all the data into the table in real time. Is there any VI in this aspect that I can refer to?

Frankly I use XY Graphs more than anything. They are a little more complicated and require you to keep your own chart history in shift registers. But they can be manipulated to display data in more ways than using a "waveform" chart or graph so IMHO they are better.

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[yehanxin]

Dear RTSLVU，

     Thank you for your long-term help. With your help, my four questions have been solved by three, and there is one problem left. Hope that your help can be solved.

    I have programmed it with the monitor function module according to your method. As shown in the red circle section below, the value of a single channel (104) can be displayed on the instrument. I did it.

Maybe I have a problem with the expression, I will re-describe the problem now.

When I started measuring 3 channel voltages，I was able to display the value of 3 voltages on the front panel of the labview.

I also want to achieve the operation，During the three voltage measurements, I can adjust the different channels by turning the button on the right side of the blue circle. After adjusting to a channel, press the “MON” button on the left, so that I can view the values of different channels at any time. Just like the driver that Aglient gave us (it software, we can't modify it). What I want is not to continuously display the data of one channel on the instrument, but to display the data of different channels through the adjustment of the buttons on the instrument panel.

This is the last question, I hope you can help me solve it.

[RTSLVU]

---

@yehanxin wrote:

Dear RTSLVU，

     Thank you for your long-term help. With your help, my four questions have been solved by three, and there is one problem left. Hope that your help can be solved.

    I have programmed it with the monitor function module according to your method. As shown in the red circle section below, the value of a single channel (104) can be displayed on the instrument. I did it.

Maybe I have a problem with the expression, I will re-describe the problem now.

When I started measuring 3 channel voltages，I was able to display the value of 3 voltages on the front panel of the labview.

I also want to achieve the operation，During the three voltage measurements, I can adjust the different channels by turning the button on the right side of the blue circle. After adjusting to a channel, press the “MON” button on the left, so that I can view the values of different channels at any time. Just like the driver that Aglient gave us (it software, we can't modify it). What I want is not to continuously display the data of one channel on the instrument, but to display the data of different channels through the adjustment of the buttons on the instrument panel.

This is the last question, I hope you can help me solve it.

---

Are you asking how to make the instrument display channels by selecting them in LabVIEW during your the time you are waiting between scans?

How about putting something like this inside your timer loop?

Obviously you will need to wire up the rest of the Monitor vi inputs. But as you see the Radio Button will select what channel the instrument is set to display. 

[yehanxin]

Dear RTSLVU，

     Thank you for your long-term help. 

    I have programmed it with the monitor function module according to your method. As shown in the red circle section below, the value of 3 channels  can be displayed on the instrument. I did it.

Maybe I have a problem with the expression, I will re-describe the problem now.

I mean: I don't want to use the Labview front panel to control the channels displayed on the instrument  screen. I mean by the buttons on the hardware, which is the agilent 34972 instrument, by manipulating them (the" rotation" button, the" Mon "button) to show what channels I want to see.  However, once the current program is run, when I press the "MON" button on the instrument, it cannot continuously display the value of one channel, but it always changes, as shown below.It has been constantly changing, constantly showing these 2 values. I want to solve this problem.