Injector pulse width

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trini99
Newbie
Posts: 2
Joined: Sun Nov 28, 2004 7:22 pm
Location: Trinidad

Injector pulse width

Post by trini99 »

I just purchased the adc212/3, I am familiar with other scopes, so I am now getting to know this scope, when I have an excessive fuel problem I like to check my injectors pulse width, I can read on the screen base on my time settings, but how do you get this to display automatically on the screen. Documentation and even your autonerdz software is a bit limited in these measurement settings and custom range settings. Any help will be greatly appreciated.

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Autonerdz
TwoWaves
TwoWaves
Posts: 387
Joined: Wed Nov 20, 2002 4:19 pm
Location: Washington State USA

Measuring Injector Pulse Width

Post by Autonerdz »

Under Settings/Measurements there are a lot of measurements you can choose that will display automatically. However, none of these will measure Injector Pulse Width accurately. This is because the injector waveform is a complex waveform and there are different types as well.

Even automotive scopes that have an injector pulse width measurement selection don't measure this well. While a saturated type driver pattern may be accurately measured, a peak and hold or pulse width modulated type pattern often will not.

The best way to measure IPW is to use the screen cursors. The difference in time between the cursors will then be displayed.

Not sure what you mean by Autonerdz software. Autonerdz is a US distributor for Pico Automotive. We do not provide any software. However, we do provide a comprehensive support package, including a library of tutorial movies, for our customers who purchase kits from us. This package can also be purchased separately. The Pico direct support is excellent. This is just in addition to that. Autonerdz has customers world wide, including one in Trinidad who purchased back in February. 8)

Not sure what you mean by limited custom range settings. Since you can design and create your own custom ranges, the only limit is how many :shock:
Tom Roberts
(The Picotologist)
Autonerdz

trini99
Newbie
Posts: 2
Joined: Sun Nov 28, 2004 7:22 pm
Location: Trinidad

Injector pulse width

Post by trini99 »

thanks for your reply, I was talking about your support package, and I did purchase the kit from autonerdz, it was purchased for me by my brother in the USA. I did realize that I can use the cursors, the time is displayed in micro seconds can it be displayed in milliseconds automatically. I know the custom ranges is limitless, but for newbees I think a little more explaination could of gone into the setting up of the scalings, at least that is just my thought. It is a great piece of equipment but using the Mac scope before it takes some getting use to and having the confidence to know what you are doing is the right thing. I am having some problems with a Nissan SSS Bluebird with the sr20 engine, I suspect a defective distributor so I am going to try it on the optical cam sensor, can you give me the best time settings to start with and any other settings that I will get a proper waveform to begin with. Thanks again for your reply

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Autonerdz
TwoWaves
TwoWaves
Posts: 387
Joined: Wed Nov 20, 2002 4:19 pm
Location: Washington State USA

settings

Post by Autonerdz »

If you email me directly and let me know your brother's name, I will check and see if you need to be plugged into our support network. You probably are not plugged in. If he got it recently, there was a CD included with our tutorial movie library as well as a PicoScope tips article. All that will answer most of your questions. Custom ranging is covered. It seems a little intimidating at first but once you have done it once, it's easy. Also, we have a new Java version Sample Rate Calculator that will help you understand how settings change your sample rate. A web version is available here:

http://www.autonerdz.com/java/SampleRateCalculator.html

For a Nissan optical distributor, you need to be sure your samples are turned up to the maximum 32,000 and you are using block mode. (They are 0-5v square waves.) You will then be able to get 12 to 14 engine revolutions on the screen before distortion. Then you can zoom in to see the detail. Start with 10ms/div to see and position the channels on the screen, then increase to 100ms/div for a long capture you can zoom in on. You can also use the 'save on trigger' record feature to write the triggered screens to your hard drive as they are captured, then review them. Be sure to watch the movie on triggering first so you understand what to avoid.
Tom Roberts
(The Picotologist)
Autonerdz

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