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We needed to make a bounceless switch for step load testing of some power supplies and the written specifications for this testing called for the use of mercury switches for their bounceless switching properties. However, we didn't have any such switches on hand nor could we find them for sale anywhere, mercury now being out of favor for safety reasons.
Therefore, we made a bouncless switch for ourselves this way:
Our power supplies passed their tests.
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Mercury wetted reed switches feature bounceless operation ...
http://www.ceejay.com/ales02.html
Use a magnet to switch, or get in the relay form for electical control.
Posted by: Mark | November 16, 2011 at 10:53 AM
That client's purchasing people couldn't find a supplier of such a switch, the mercury hazmat issue being reported back to me as the problem.
I decided not to get into that issue. Instead, the ball of foil was a whole lot quicker way for me to get the testing done than having to deal with the reported mercury switch availabliity problem.
Posted by: John Dunn | November 16, 2011 at 11:18 AM
I suspect the alligator clip alone had the contact resistance of a power MOSFET. in the 10~20mΩ region, possibly much more.
Posted by: Tony Stewart | November 19, 2011 at 08:46 PM
Compared to the load resistances being switched, the alligator clip wasn't a problem.
Posted by: John Dunn | November 19, 2011 at 10:02 PM