Post by thread:[EE]: slightly [OT]: 240 Vdc to 12 Vdc invertor

We are in need of a 240 Volt DC to 12 Volt DC converter of some fashion, this could be a 240 Volt DC to 240 or 120 Volt AC or Directly from DC to DC. The 240 Volt DC source is a bit dirty, ranging around 250 Vdc with spikes and surges both high and low due to the fact that it is being supplied through 2 iron tracks + iron wheels and bearings (bit tough on the bearings). This is in an extremely hostile environment (molten iron being poured) so the unit should either be capable of being mounted inside the air conditioned cab, or capable of operating in an extremely hot environment. Lonnie - KF4HAZ - -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

source=What is your DC current consumption requirement. What regulation accuracy is required? Do you have inductive loads? I have assumed that your primary source is 240VDC? -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

KF4HAZ wrote: > We are in need of a 240 Volt DC to 12 Volt DC converter > of some fashion, this could be a 240 Volt DC to 240 or 120 > Volt AC or Directly from DC to DC. Perhaps PC power supply would match. Mike. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

Yes! Now that's good. I had been watching this thread for awhile, wondering what people would come up with and not getting any good ideas myself. That is great. ---- Original message ---- >Date: Fri, 20 Sep 2002 18:02:30 +0300 >From: Mike Singer <spam_OUTmikeTakeThisOuTPOLUOSTROV.NET> >Subject: Re: [EE]: slightly [OT]: 240 Vdc to 12 Vdc invertor >To: .....PICLISTKILLspam@spam@MITVMA.MIT.EDU > >KF4HAZ wrote: >> We are in need of a 240 Volt DC to 12 Volt DC converter >> of some fashion, this could be a 240 Volt DC to 240 or 120 >> Volt AC or Directly from DC to DC. > > Perhaps PC power supply would match. > > Mike. -- Mike P. MTP Technologies KC0LLX -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

source=Sorry, must be me, still don't understand the application. Where is this 240 volts........DC coming from. Are trying to regulate 240VDC to 12V? Still don't know what your accuracy & consumption factors are! As per the PC supplies, they work OK with nice current on +12V with line regulation of 5 to 7%. If you ever need the 5VDC output, you'll need to satisfy the 5V sense on them so that the Main 5V doesn't clamp. Just add a jumper. I guess that's great! -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

source=I know that you've got all the answers your looking for in regards to your inverter and the PC supply. Here some additonal literature on inverters. Try chapter #4 I think. http://www.pwrx.com/pwrx/app/solid_st.pdf Please let us know your final results. It's a useful project. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

Mike P. > Yes! Now that's good. I had been watching this thread for > awhile, wondering what people would come up with and not > getting any good ideas myself. That is great. > > >From: Mike Singer <mikeKILLspamPOLUOSTROV.NET> > > > >KF4HAZ wrote: > >> We are in need of a 240 Volt DC to 12 Volt DC converter > >> of some fashion, this could be a 240 Volt DC to 240 or 120 > >> Volt AC or Directly from DC to DC. > > > > Perhaps PC power supply would match. > > > > Mike. > -- > Mike P. That may not be as great as you think. Usually stabilized is the only 5v output, so you have to provide some min load to 5v output. And then due to 12v loop internal resistance you may get 12v dropped to ~11v at a max 12v load. Mike. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

That depends on the supply. Many nowdays do not require a minimum load. Besides, any switching power supply would work on the same principle, and they are available with 12V only outputs. ---- Original message ---- >Date: Sat, 21 Sep 2002 06:11:21 +0300 >From: Mike Singer <.....mikeKILLspam.....POLUOSTROV.NET> >Subject: Re: [EE]: slightly [OT]: 240 Vdc to 12 Vdc invertor >To: EraseMEPICLISTspam_OUTTakeThisOuTMITVMA.MIT.EDU > >Mike P. >> Yes! Now that's good. I had been watching this thread for >> awhile, wondering what people would come up with and not >> getting any good ideas myself. That is great. >> >> >From: Mike Singer <mikespam_OUTPOLUOSTROV.NET> >> > >> >KF4HAZ wrote: >> >> We are in need of a 240 Volt DC to 12 Volt DC converter >> >> of some fashion, this could be a 240 Volt DC to 240 or 120 {Quote hidden}>> >> Volt AC or Directly from DC to DC. >> > >> > Perhaps PC power supply would match. >> > >> > Mike. >> -- >> Mike P. > > That may not be as great as you think. > Usually stabilized is the only 5v output, so you have to >provide some min load to 5v output. And then due to >12v loop internal resistance you may get 12v dropped >to ~11v at a max 12v load. > > Mike. > >-- >http://www.piclist.com hint: The list server can filter out subtopics >(like ads or off topics) for you. See http://www.piclist.com/#topics > > -- Mike P. MTP Technologies KC0LLX -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

Have found many for converting 12vDC to 240vAC but none for 240vDC to 12vDC or 240vDC to 240vAC am considering using a triangle wave driving a pair of H-bridges (one driven through an inverting-op-amp) but of course I will have to build a suitable supply for this to run from the 240Vdc. We are in need of a 240 Volt DC to 12 Volt DC converter of some fashion, this could be a 240 Volt DC to 240 or 120 Volt AC or Directly from DC to DC. The 240 Volt DC source is a bit dirty, ranging around 250 Vdc with spikes and surges both high and low due to the fact that it is being supplied through 2 iron tracks + iron wheels and bearings (bit tough on the bearings). This is in an extremely hostile environment (molten iron being poured) so the unit should either be capable of being mounted inside the air conditioned cab, or capable of operating in an extremely hot environment. Will require 10 amps average on the 12 volt DC side 20 amps peak. P.S. actual readings show anywhere from 208 Vdc (when the motors are loading-up to 277 Vdc when they first disengage. Lonnie - KF4HAZ - -- http://www.piclist.com hint: To leave the PICList @spam@piclist-unsubscribe-requestKILLspammitvma.mit.edu