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control contact of a Relay

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control contact of a Relay

Postby Schranzy » Mon Sep 10, 2012 1:39 pm

I will tell you now the whole problem about the measurement task, maybe you can give me better support. I have to control one contact of a relay, as starting point of the measure I have the digital relay control signal. When the control signal is going to high I should measure the time to the point when the signal from the contact is going to low. Also I have to check if the contact signal is low over the whole time to the next trigger pule from the control signal. The control signal is a 12V DC voltage, the signal from the contact is 50V AC voltage, The device is a PicoScope 6402 and I am working with LabView 2011. I am sure that these measurement task can be done with the device but now I am trying about 2 Weeks to do these but something I do wrong. Please help me you are my last chance.
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Re: control contact of a Relay

Postby Martyn » Tue Sep 11, 2012 10:04 am

Are you able to see the waveform, and the data, for the events that you wish to measure the time between ?
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Re: control contact of a Relay

Postby Schranzy » Tue Sep 11, 2012 1:20 pm

Yes, to see the Stream Data is no problem. At the moment I am displaying the wave with a diagram.
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Re: control contact of a Relay

Postby Martyn » Tue Sep 11, 2012 2:08 pm

To display the data you must have data in a buffer, or be able to look at values before displaying on the screen, which means you only need to look at the number of samples that occur between the two points you wish to measure and multiply this by the sample interval you are using.
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Re: control contact of a Relay

Postby Schranzy » Wed Sep 12, 2012 6:28 am

I had tryed tries sometimes left but something was wrong because the time between these two events is approximately 30ms mesured by PicoScope 6. When I measured the Time with LabView the way you describe it the results are around 200ms. Can you post me some examples or something els?
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Re: control contact of a Relay

Postby Martyn » Wed Sep 12, 2012 7:39 am

Can you attach the psdata file from PicoScope6 for your signals so that we can look at the relevant settings.

Can you specify the parameters you are passing to ps6000RunStreamingCall in your vi, and what value is being returned in the sampleInterval parameter.
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Re: control contact of a Relay

Postby Schranzy » Wed Sep 12, 2012 8:33 am

Sorry the psdata is to big to uploading it. But her you can see a picture.

Sample Interval: 1000
Pre-trigger Samples: 0
Post-trigger Sampls: 1000
Down-sample mode: none
Down-Sample Ration: 1
Attachments
Signal.jpg
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Re: control contact of a Relay

Postby Martyn » Wed Sep 12, 2012 8:44 am

If you SaveCurrentWaveform as it should be small enough to post.

Can you put cursors on as well so that I can see what you are trying to measure.

then get your Labview vi to output the data points for the appropriate channel to a txt file and post that data as well.

Finally what setting do you have for "PS6000_TIME_UNITS sampleIntervalTimeUnits" in your vi.
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Re: control contact of a Relay

Postby Schranzy » Wed Sep 12, 2012 9:40 am

Sry but the psdata is also to big. What I want to measure is the time between the moment when the blue signal is going to high and the moment when the red signals amplitude is going to 0. And also i have to ensure that the red signal is 0 over the whole time to the next puls from the blue signal.

What should I display to a txt document?
I dont have more setting options, do I use the wrong vi?

At the beginning I use PS6000 Open than the Settings Vi and now the Stream, at least the Get Stre Vi. Is these corect.
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Re: control contact of a Relay

Postby Martyn » Wed Sep 12, 2012 10:37 am

The psdata file for one capture in streaming should be under 100k so should be fine, so not sure what is happening there. Try sending it attached to an email on the helpdesk ticket.

I meant that you would need to amend your vi to add in a section to save the data to a txt file at the same time as it displays it to screen. Sample number, value on channel A, and value on Channel B will be fine.
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Re: control contact of a Relay

Postby Schranzy » Wed Sep 12, 2012 11:22 am

can we talk over email because it is much more quickly than forum? here is my adress: kaiuwe.bentele@gruner.de
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Re: control contact of a Relay

Postby Martyn » Thu Sep 13, 2012 6:27 am

You should have received an email from us
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