Take Two with oscilloscope
Added 2023-03-23 01:04:46 +0000 UTCThe first section of this video is identical, but there are two new sections with more detail including the use of an oscilloscope to confirm that the unit is indeed switching voltages.
Thanks to Andy Brown for the extra information about why the voltage is switched.
It's not for reducing power dissipation, but instead the lower magnetic field collapses faster when the injector is turned off, and results in faster valve closing.
A bit of post-video probing shows quite a high voltage drop across the regulator under load. 12V off load and 8V with a 10 ohm resistor as a load.
https://www.youtube.com/watch?v=qAwDKS91sZI
Comments
Yeah, the 9V thing is a nuisance. This was the first time trying it out.
Big Clive
2023-04-02 23:52:29 +0000 UTCI see you're using your £20 oscilloscope. Running off 9V is a pain; luckily these are very hackable. This I did for my son so it runs off USB https://drive.google.com/drive/folders/1t4JmrZ9NiKye6XGk2TvIdLMI5QXKXeLw?usp=share_link and this runs off a battery and charges off USB https://drive.google.com/drive/folders/1BgwORd2hIZ03l4bfx5QXJpAs2RHAzCge?usp=share_link
Gordo
2023-04-02 19:25:03 +0000 UTCIt's rare that I do detailed editing. Usually just splicing sections and occasionally trimming bits down.
Big Clive
2023-03-24 16:29:00 +0000 UTCClive, would you happen to have been in the situation where you actually had to do some video editing :) ?
lImbus924
2023-03-24 14:48:59 +0000 UTCThe two-button mode change could be a safety feature - perhaps to avoid unintentionally squirting loads of petrol around. Dual-voltage drive is normal for stepper motors - and a solenoid isn't much different. The initial voltage is for rapid current increase through the inductive part of the load, the latter is to maintain the current (F = BLI) through the resistive part. Yes, power dissipation is a concern but also longevity. No point caning it and halving the life.
Mike Page
2023-03-23 14:46:34 +0000 UTC
