Those of you who accessed the resource list I posted a while back may have noticed the section that discusses some content on the basics behind how induction motors work that I have been working on with the Pacific Energy Center. At the time I developed the resource list, we only had the slides put together, along with some home-shot video clips of experiments that you could try.
Since then, we have converted the slides to video presentations with narration and put them up on the web. The purpose of this post is to let you know about this new resource and show you how to get access it. The first step in the process is to navigate to the Pacific Energy Center Online Class Management Center, which should put you at a page that looks like this.
Select “Login as a guest” and you should be directed to a page that looks something like this.
From this point, select “Induction Motor Theory” from the drop-down “Courses” menu on the left.
That should take you to a page that looks like this.
From this point, you should be able to select a file and when you do, it should open up in a separate window and play as a video presentation.
When Internet Explorer 9 installed itself on my machine, I initially had a problem getting the video to work with it. It did work with Firefox 3.6.18 and Chrome 18.0.1025.151. So, if you have problems, you may find it easier to just try one of those browsers.
But, I discovered that, at least for my system, I could fix the problem by following a procedure that made Windows media player the default. I’m reproducing it here because I could not figure out how to link to the post directly and it worked for me. I found this on a site called the birdforum from a user named Andrew Rowlands.
- I assume everyone is using windows 7 and IE9.
- In IE9 Goto Tools :: Internet Options :: Programs Tab :: Set Programs (near the bottom)
- Now this prompt some of you may have been to before only this time select the last option, Set Program Access and Computer Defaults.
- Select Custom then scroll down the list till you see choose a default media player. I unchecked iTunes and Quicktime but you you could also just click the radio button next to Windows Media Player and that will work as well.
Hope this works for everyone.
EDIT: This will also work for all other filetypes that were opening up in quicktime instead of windows media player.
I should also mention that the PEC’s “On Demand Content” site is fairly new and there may be some issues with it. If you have trouble accessing the content, please let Ryan Stroupe (R2S2@pge.com) at the Pacific Energy Center know so he can have someone look into the issue.
If you do experience problems, older, development versions of the files are still available to you if you are interested in them via YouTube and Google Documents. The video is narrated but the slides currently are not. Specifically, the following content is available:
- A video segment on YouTubeof an experiment you can perform at home to demonstrate induction principles.
- A PowerPoint slide show in a public Google Documents folder that covers the basic theory behind three phase induction motor operation.
- A PowerPoint slide show in a public Google Documents folder that covers induction motor characteristics, including how variables like efficiency, speed, power factor, kW, and amperage vary with load, a discussion of torque vs. speed curves, and a discussion of how the moment of inertia of a load interacts with the motor torque characteristic to accelerate (or not) the load.
You can view the slides on the Google Documents web site, but you can also download the presentation and view it on your laptop. The advantage to the latter is that you can run it as a PowerPoint show, which will allow the animations that are built in the slides to work. This may make some of the points easier to understand vs. viewing the unanimated slides. If you don’t have PowerPoint, you can download a free PowerPoint viewer from the Microsoft web site.
We are still in the process of developing more professional video of the experiments, so for now, you will still need to go look at them on the YouTube site I mention in the reading list. But eventually, they too will be on the PEC’s On Demand Content site, along with the slides.
Senior Engineer – Facility Dynamics Engineering