ADP5250 Logging/Recording

[tfkrauss]

Hello,

I am currently using an ADP 5250 and I need to record data over approximately 2-5 minute periods. My understanding is that the record function in the scope is not available for this model so I was wondering what options I have for recording data at a high resolution.

I've tried using the logger tool, however the data it records does not accurately reflect what the scope shows me so I am not sure what the issue is. Additionally, it seems to only record one data point per second. What options may I have for accurately plotting data over time with higher resolution? 

 

Thank you!

[Jeffrey]

Hello @tfkrauss

the WAVEFORMS logger defaults to 1 sample per second, and max's out at 10 S/s (100 mS/sample)

I'm unclear what you mean by "recording at high resolution".  Assuming you mean at a high sample rate?  What rate?

There is an example in the WaveFormsSDK titled AnalogIn_Acquisition.py, it demonstrates sampling at 20 MHz with a buffer size of 4000 samples.

I have a VB.NET version of this example if you prefer.

In either case, you would need to flesh out this example by adding the ability to save the collected data to file.

There are plenty of resources on line demonstrating writing data to file.

[tfkrauss]

1 hour ago, Jeffrey said:

Hello @tfkrauss

the WAVEFORMS logger defaults to 1 sample per second, and max's out at 10 S/s (100 mS/sample)

I'm unclear what you mean by "recording at high resolution".  Assuming you mean at a high sample rate?  What rate?

There is an example in the WaveFormsSDK titled AnalogIn_Acquisition.py, it demonstrates sampling at 20 MHz with a buffer size of 4000 samples.

I have a VB.NET version of this example if you prefer.

In either case, you would need to flesh out this example by adding the ability to save the collected data to file.

There are plenty of resources on line demonstrating writing data to file.

Hi Jeffrey, thank you for the response. I actually overlooked the Update setting on the logger. I think 10 samples/sec will be sufficient for the time being.

I think I may be using the logger wrong in some way. I've been testing by touching and releasing the probe with my finger to see what readings I get. When I use the scope, it seems accurate with 0 mV when nothings touching it and about 50 mV when I touch it with my fingers. With the logger, there seems to be a lot of noise and offset. Without having a probe attached/without touching the probe, both channels 1 and 2 do not read 0. When I touch the probe, the readings change by about 20-40 mV but the offset is very significant. Is there a reason for this? 

Also, sorry if this is a basic question, I've just recently started using the ADP and thank you for the help!

 

[Jeffrey]

Most data acquisition devices don't read 0V when nothing is attached.

Their inputs are high impedance so they only require a tiny amount of current.  Because of this trait, they act like antennae.  So with nothing attached, you cannot trust what you see.  you need to have a known input source or signal attached else.

Using  the capacitance/static electricity on your fingers is a good test to see if the device is responding but that is all that test is worth.  Keep in mind that an abundance of static could damage the instrument due to the static discharge, so it is not recommended.

[tfkrauss]

On 9/16/2022 at 5:34 AM, Jeffrey said:

Most data acquisition devices don't read 0V when nothing is attached.

Their inputs are high impedance so they only require a tiny amount of current.  Because of this trait, they act like antennae.  So with nothing attached, you cannot trust what you see.  you need to have a known input source or signal attached else.

Using  the capacitance/static electricity on your fingers is a good test to see if the device is responding but that is all that test is worth.  Keep in mind that an abundance of static could damage the instrument due to the static discharge, so it is not recommended.

Thank you for the response. I'm still a bit confused as to why the numbers are different from the logger versus the scope when something is attached (when I touch it with my fingers). And thank you for the advice as well, I did not know it could cause damage.