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how to generate continuous voltage generation during 1.4 ms

Hi everyone,

 

I am studying on a combustion chamber test setup. I need to send a continuous voltage to a spark plug for 1.4 ms after running the program. I need some doubts about the preparation of the program for this purpose.

 

1) Can I adjust delay, duration, wait, etc. as a floating number mili seconds like 1.2 ms via software timing by use of wait or wait to next functions?

2) I have never worked with hardware timing, so I do not know much about it. Should I use hardware timing? Can I adjust timing by giving as a floating number? (by the way I will use NI USB X 6353)

 

I have checked all example analog output vis of labview 2012, however, I could not adapt them to my task.

 

I am open all kind of suggestions about this. Thanks in advance.

Egemen
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Egemen,

 

What type of spark coil are you using?  You mentioned analog output, but most of my experience with controlling spark requires digital TTL outputs ("smart" coil) or high voltage spark driver outputs.  Therefore, we typically drive spark with either the NI 9754 ESTTL module or the older Drivven Spark module.  Also, I assume this is not an engine-synchronous application?

 

Most of the NI Powertrain Controls VIs are centered around NI LabVIEW Real-Time and FPGA due to the need for a high level of determinism and speed, but you may be able to adapt some of the VIs for your purpose.  I would recommend downloading the NI-PCG device drivers from this link.  Maybe the examples will give you some insight.  Best,

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I do not know about the exact model and features of it, however, I think that it is a standard one produced by Bosch. My advisor just talked about the program which starts the ignition. I am studying on a constant volume combustion chamber, not an engine. We can amplify the signal voltages with amplifiers I think. I'll check these examples, thank you very much for it.
Egemen
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I learned that it is possible to give a delay or duration less than 1 ms by use of software timing methods, since Windows OS time resolution is 1 ms (I have read these threads: delay 1 ms  & looping less than 1 ms). I wish that it would be possible by usehardware timing. Can I do it with NI USB-X 6353 daq? How can I generate an analog voltage during 1.4 ms with NI 6353?

Egemen
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You should be using hardware timing for a precise signal. There are numerous examples that you should be able to adapt. You can create a waveform with a dt that you specify and of a specific length. That is all you need.
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Thank you Dennis_Knutson. I have been trying to understand and adapt some couple of examples provided by Labview. However, I have not succeeded it yet. I am trying to adapt Voltage (non-regeneration) - Continuous Output.vi, but I cannot do that. I really do not understand this vi. It is not quick responsible. When I tried it to light of a led to learn how it works, I realized that it is not a quick responsive vi. When I change the amplitude to turn of the led, it takes a while to affect after the entering the value in the amplitude. Additionaly, when I look the functions for waveform generations, I saw that all of them provides you a range between - and + values. However, for instance, I want it to be between 0 and +14. And I do not want a continuous signal generation. I just want a finite signal generation with amplitude of 14 and time of 1.4 ms. I tried to use "build waveform" function to change the dt to get 1.4 ms, however, I cannot do that.

Lastly, I have changed Voltage - Finite Output.vi example, however, I am not sure that I modified it correctly. And I do not know how to modify he waveform range as it is from 0 to 14 volts. Could you look at the attached vi to check that I do it correctly?

I know these are very simple vis, however, I have never worked with hardware timing and waveforms. Sorry for that. Thanks in advance.

 

Egemen
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