Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th January 2003, 05:35 AM   #1
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
Default Using 120V transformers with 240V supply

I'm building PS to be used with 240V AC. However, the only transformers I have at my disposal are the ones specified for 120V. Can I use 2 transformers with their primaries in series and effectively used with 240V supply? Is it the same as using ea. transformer with 120V supply or am I missing something here?
__________________
www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC
  Reply With Quote
Old 15th January 2003, 06:50 AM   #2
sangram is offline sangram  India
diyAudio Member
 
Join Date: Sep 2002
Location: India
Linguistic battles aside...

Yes

I missed it too...

Paying for stupid mistake.

Great little idea about the auto (tranny, trafo, whatever)...
  Reply With Quote
Old 15th January 2003, 07:03 AM   #3
Warp Engineer
On Holiday
 
AudioFreak's Avatar
 
Join Date: Oct 2001
Location: Queensland, Australia
That'll be fine Peter.
  Reply With Quote
Old 15th January 2003, 07:13 AM   #4
sangram is offline sangram  India
diyAudio Member
 
Join Date: Sep 2002
Location: India
Quote:
Originally posted by AudioFreak
That'll be fine Peter.
Yeah but if you have varying loads on the two transformers you will have problems.

I am currently running the PM 665 with the two transformers in series. I will put in the auto transformer anyway as I don't want to blow anything to bits, ever...
  Reply With Quote
Old 15th January 2003, 07:21 AM   #5
Warp Engineer
On Holiday
 
AudioFreak's Avatar
 
Join Date: Oct 2001
Location: Queensland, Australia
Quote:
Originally posted by sangram
Yeah but if you have varying loads on the two transformers you will have problems.
True. I should have said.. As long as the total VA being drawn off the secondary side of each transformer is equal, it'll be fine.

To achieve that, assuming that both transformers are near to identical, you could run the secondaries of each transformer in parallel. ie. secondary winding #1 on transformer #1 in parallel with secondary winding #1 on transformer #2 and secondary winding #2 on transformer #1 in parallel with secondary winding #2 on transformer #2.
  Reply With Quote
Old 15th January 2003, 11:12 AM   #6
yeti is offline yeti  Germany
diyAudio Member
 
Join Date: Nov 2001
Location: Ewersbach
It's easy, just wire the primaries in series and the secondaries in parallel, but check the sense of the windings!

Arne
  Reply With Quote
Old 15th January 2003, 12:03 PM   #7
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Default 240v trannies

Peter,

It should work, but if the trannies are not completely identical (and half a winding secondary may be enough) you will connect in parallel two unequal voltage sources which will cause a relatively high circulating current heating up the tranny for no reason and robbing you of available power.

I would advice to check the loaded output of each secondary and if there is more than a few hundred mV difference, if that is an option, to use each secondary for one polarity of the supply.


Jan Didden

PS I forgot, but I had a similar case where I added one turn to one tranny to get them equal. May also be possible.
  Reply With Quote
Old 15th January 2003, 12:33 PM   #8
diyAudio Member
 
Peter Daniel's Avatar
 
Join Date: Jul 2002
Location: Toronto, Canada
Send a message via AIM to Peter Daniel
The transformers are identical and they have only one secondary ea. I was thinking about using each secondary for one polarity of the supply for the gainclone.
__________________
www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC
  Reply With Quote
Old 16th January 2003, 12:46 AM   #9
Warp Engineer
On Holiday
 
AudioFreak's Avatar
 
Join Date: Oct 2001
Location: Queensland, Australia
Not a good idea unless you can be sure that the VA drawn from both transformers are identical.
  Reply With Quote
Old 16th January 2003, 12:56 AM   #10
blmn is offline blmn  Brazil
diyAudio Member
 
blmn's Avatar
 
Join Date: Feb 2001
Location: .
Peter,

No problems if you're using the secondaries in series feeding the same amp(s) because (full wave ct schema to have v+ and v-, for example).

regards
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
120v/240v amplifiers dsiroky Solid State 1 25th September 2008 11:58 AM
Spacedeck 240V to 120V lt_texan Analogue Source 3 10th December 2007 02:41 AM
Two 120V transformers in series for 240V ? Bernhard Power Supplies 8 22nd November 2005 12:28 AM
amp 120v-240v conversion chrish Solid State 10 12th December 2004 09:49 AM
toroid rewiring from 240v to 120v pjb Parts 3 22nd February 2004 01:28 PM


New To Site? Need Help?

All times are GMT. The time now is 01:48 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2