Re: [CAD_CAM_EDM_DRO] Sanity Check on Power Supply Capacitor Size

Luke, I think you need to take into account that although the voltage increases by 1.414 after rectification, the amperage decreases by a factor of 1.8. Using 9.2 amps, Should be 29,000+ mF And higher than 25 VDC.

Ron

luke1027@... wrote:
Sanity Check

Filter Capacitor Size for Power Supply based on:
C=(80,000*I)/V
Transformer (secondary tap) will be putting out (18V * 1.414=25.5V) with
8.3A*2=16.6A (since it is wired in parallel).
With these specs I get C=(80,000 * 16.666)/25.452=52,386 Microfarads.

So the filter capacitor size I need must be at least 52,386 Microfarads?
Is this calculated correctly? Boy, that seem high … does it not?

Back Ground info:

I am building a Power Supply to drive my stepper motors out of two Transformers
(http://www.surpluscenter.com/item.asp?UID=2005071308202974&catname=&qty=1&item=15-1176)
in wired in a Parallel circuit. My schematic is shown here:
http://www.pennswoods.net/~luke1027/PS_Schematic.jpg




Addresses:
FAQ: http://www.ktmarketing.com/faq.html
FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/
Post Messages: CAD_CAM_EDM_DRO@yahoogroups.com

Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@..., timg@...
Moderator: pentam@... indigo_red@... davemucha@... [Moderators]
URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO

OFF Topic POSTS: General Machining
If you wish to post on unlimited OT subjects goto: aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if you have trouble.
http://www.metalworking.com/news_servers.html

http://groups.yahoo.com/group/jobshophomeshop I consider this to be a sister site to the CCED group, as many of the same members are there, for OT subjects, that are not allowed on the CCED list.

NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........
bill
List Mom
List Owner


Yahoo! Groups Links








[Non-text portions of this message have been removed]