So the current that flows through the LED is _about_ 55V/3,200 Ohms = 0.017A, or 17 mA. Quite reasonable for the LED. But the resistor will need to dissipate I^2 * R power, or (0.017A)*(0.017A)*(3,200 Ohms) or about 1 watt. This is not your common 1/4 watt resistor... You could use (4) 12 or 13K 1/4 watt resistors in parallel, or better yet (5) 16ishK resistors, or (6) 20ish K resistors in parallel... you get the idea.
There really should be a power supply FAQ... but unfortunately I don't have the time to work on one now. - Steven Ciciora At 06:36 PM 10/25/2004 +0100, you wrote: >2 lamps in series would be fine - but when 1 blows / dies both will go out ! > >LED's work fine with DC - BUT you do need a series resistor to limit the >current to about 10/15 milli Amp >- a good rule is about 820 Ohms for 12 Volts - So for 55 Volts 3,200 Ohms >should do the trick. > >Remember that LEDS are like diodes - they only work one way round on DC, so >if >it don't work this time - turn the LED connections arround. > >One more thing - If you have BIG caps in your power supply the LED could >well >stay on for a LONG time after you ditch the power ! > >Rgds > >Dave Fisher UK > > >-----Original Message----- >From: Torsten [mailto:[EMAIL PROTECTED] >Sent: 25 October 2004 18:17 >To: [EMAIL PROTECTED] >Subject: [CAD_CAM_EDM_DRO] Two Lamps? > > > > >Got a question, I have a Powersupply >delivering 55 volts DC in my driverbox >connected to a Caps to store and smuth >out the current having been zapped a few >times I would like to hook up a little >light bulb to drain out the current after >it is shut off. >Would also be nice for the visual feedback >to see when the thing is charged. > >On the first attempt I learned that a Led dose >not work with DC current. > >So now I am Looking at some Bulbs with a filament. >What I found is a "Miniature Bayonet base Lamp" >rated for 28 volt .040 amps I belive I should be >able to wire two of them in serial to make it work >on my 55 volt system. > >Will this work? >Any thoughts, please share. > > > > > > > >Addresses: >FAQ: http://www.ktmarketing.com/faq.html >FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/ >Post Messages: [EMAIL PROTECTED] > >Subscribe: [EMAIL PROTECTED] >Unsubscribe: [EMAIL PROTECTED] >List owner: [EMAIL PROTECTED], [EMAIL PROTECTED], >[EMAIL PROTECTED] >Moderator: [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] >[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 > > > > > > > > > > > >Addresses: >FAQ: http://www.ktmarketing.com/faq.html >FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/ >Post Messages: [EMAIL PROTECTED] > >Subscribe: [EMAIL PROTECTED] >Unsubscribe: [EMAIL PROTECTED] >List owner: [EMAIL PROTECTED], [EMAIL PROTECTED], >[EMAIL PROTECTED] >Moderator: [EMAIL PROTECTED] [EMAIL PROTECTED] >[EMAIL PROTECTED] [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 > > > > Addresses: FAQ: http://www.ktmarketing.com/faq.html FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/ Post Messages: [EMAIL PROTECTED] Subscribe: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] List owner: [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED] Moderator: [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] [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 <*> To visit your group on the web, go to: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
