27 lines
1.6 KiB
HTML
27 lines
1.6 KiB
HTML
define(`TITLE', `Measuring the speed of a salad spinner')
|
|
define(`DATE', `2014-12-11')
|
|
define(`CONTENT', `
|
|
Have you ever been wondering with how many revolutions your salad spinner is running? Here is the measuring:
|
|
|
|
First, attach a hall-probe to the salad spinner bowl, the exact position needs to be found by experiment:
|
|
|
|
<a href="http://a385e-5.de/wp-content/uploads/IMG_2597.jpg"><img src="http://a385e-5.de/wp-content/uploads/IMG_2597-300x225.jpg" alt="IMG_2597" width="300" height="225" class="alignnone size-medium wp-image-507" /></a>
|
|
|
|
Second, attach two small but strong magnets at the spinner, one on each side, to let it run weighty:
|
|
|
|
<a href="http://a385e5.files.wordpress.com/2014/12/img_2600.jpg"><img src="http://a385e-5.de/wp-content/uploads/IMG_2600-300x225.jpg" alt="IMG_2600" width="300" height="225" class="alignnone size-medium wp-image-508" /></a>
|
|
|
|
Third, connect the probe to a power-supply, an oscilloscope and a frequency-counter:
|
|
|
|
<a href="http://a385e-5.de/wp-content/uploads/IMG_2599.jpg"><img src="http://a385e-5.de/wp-content/uploads/IMG_2599-300x225.jpg" alt="IMG_2599" width="300" height="225" class="alignnone size-medium wp-image-509" /></a>
|
|
|
|
The oscilloscope is required to find the right position of the probe, the counter is required for the actually measurement.
|
|
|
|
And then: turn the spinner:
|
|
|
|
[youtube https://www.youtube.com/watch?v=ezTvoh3vguI&w=560&h=315]
|
|
|
|
Here, in this clip, we measured about 43Hz. In another test it was even 52Hz.
|
|
|
|
Since we have two magnets, we had 21.5 rps and in the other test 26 rps. These are 1290 rpm and 1560 rpm. That'`s fast.
|
|
') |