Anodizer power supply questions

[fitzo]

BTW, since it's a lab DC supply, it will probably be both "safe" and very clean power. We had DC supplies for doing something called electrophoresis (like in DNA analysis) and they had to be VERY exacting and reproducible.

 

[pso]

John

The DC motor controller may or may not work for you. They only simmulate the desired DC voltage. The bench supplies that the other guys, like Fitzo, are using produce a true DC output. The DC motor controllers alternately connect and disconnect the output to/from an internal DC supply of about 170V or so. The on-times and off-times are varied so that the average is the desired output voltage. This switching action will take place at a rate of anywhere from 1000 to over 30000 times a second. Your meter will not be able to detect the switching and will just give you an approximate average DC value. If the DC motor controller you have has a really good filter on it's output, you will get a good approximation of a constant DC voltage, with very little AC ripple. It may be worth a try. Just make sure that you have proper fusing or circuit breakers since the DC controller was not meant for this sort of application. Your results may be quite different from what the people using a true DC supply would get, even though your meter gives the same reading.

I did a search for "lab power supply", "bench DC supply" and various combinations of the same words on E-Bay and found the following:

0-30V, 0-5A adjustable - you may need two or more in series to get the desired voltage
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=48708&item=5785809873&rd=1&ssPageName=WDVW

tripple supply - can get up to 65V, 0-3A
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=58288&item=7527380620&rd=1&ssPageName=WDVW

Heck, we could use a few more of these at work!

You may also find simmilar equipment for less at a local surplus electronics store and save on the shipping (they should be pretty heavy). Just make sure it works before buying it if it is used.

Good luck.

Phil