Power transformer amperage - diyAudio
 Power transformer amperage
 User Name Stay logged in? Password
 Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read Search

 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
 26th April 2010, 07:08 AM #1 diyAudio Member   Join Date: Oct 2007 Power transformer amperage I have a couple of PT and I know their's secondary voltage, but no idea of max current... I know its power could be obtained from some formulae from the core size. Do anyone know this calculations? Thanks!
 26th April 2010, 07:57 AM #2 diyAudio Member   Join Date: Mar 2010 Look in a transformer catalog for a transformer of similar weight and that will bring you somewhat close to knowing the power capability. Divide that by the voltage and you have current. A more accurate way would be to pick open the transformer and measure the wire size. Another way is to load the transformer and measure the temperature rise. Heat in a transformer comes from core losses and copper losses. When there is no load, you only have core losses. Typically, copper and core losses are about equal at full load.
 26th April 2010, 11:02 AM #3 diyAudio Moderator     Join Date: May 2003 Location: Palatiw, Pasig City from the radio designer's handbook: power = (A*5.5)squared. A is the cross-section area in square inches, so that is center leg width x depth of stack. __________________ the best advertisement for a good audio design is the number of diy'ers wanting to build it after all the years....never the say so of so called gurus....
 28th April 2010, 07:59 PM #4 diyAudio Member   Join Date: Oct 2007 I think I made those calculations... but got wrong numbers, that's for sure! I was refering to that formulae that includes completly all core's data (height, depth, width)... but I think I'll try again!
 28th April 2010, 08:35 PM #5 diyAudio Moderator     Join Date: May 2003 Location: Palatiw, Pasig City no, just the area under the coil.....tounge width x stack height, that is your core area, factor in 0.9 and you're done.... __________________ the best advertisement for a good audio design is the number of diy'ers wanting to build it after all the years....never the say so of so called gurus....
 29th April 2010, 01:44 PM #6 diyAudio Member   Join Date: Nov 2007 Location: Denver, Colorado Power handling before saturation would have to do with core size, but power is more than just current. It has to do with current and voltage. The poster asked about current which should have to do with winding wire cross sectional area. Knowing this he could find the max current the winding could handle. Then he could apply that limit and the core cross sectional area to figure the power it could handle. I think you would want both parameters to be able to spec your transformer appropriately.
 30th April 2010, 07:42 AM #7 diyAudio Moderator     Join Date: May 2003 Location: Palatiw, Pasig City yes, that is the idea..... __________________ the best advertisement for a good audio design is the number of diy'ers wanting to build it after all the years....never the say so of so called gurus....
 1st May 2010, 07:54 AM #8 diyAudio Member   Join Date: Dec 2009 Dear, I Think there are a variaty of cores and so, calculation from core was not proper. The designer may design at a higher side or lower side flux dencity. But surely, the current carrying Capacity depending directly on the coil conductor. If you know the voltage of primary & secondary, It is very easy for you. The capacity is limited by the bottleneck criteria. Just check SWG of the terminal and No of parallel conductor if any. It will determine your Secondary Current Rating. Now calculate your primary current for that secondary current. Now check the primary coil wire SWG is sufficient or not. If Yes, ur secondary Voltage x Secondary current is the VA Capacity of transformer. and if not, primary current will limit the VA Rating and then Primary voltage x current be the VA of the transformer. To measure paralling of conductor in the secondary, you may check the coil resistance and fair idea will be achieved. ============================================ Please Note: In Electrical Engg, Transformer Rating is in VA or KVA but Not in Watt of KW. For Electronics Plz consider 0.8 as PF for safety. ============================================ Thanks

 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 OffTrackbacks are Off Pingbacks are Off Refbacks are Off Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post kizm0 Chip Amps 3 21st July 2009 01:25 PM rtill Solid State 13 24th January 2008 10:21 AM jarthel Parts 32 2nd August 2006 02:06 PM cantskienuf Chip Amps 0 14th September 2004 12:25 AM jarthel Parts 1 9th July 2003 06:01 AM

 New To Site? Need Help?

All times are GMT. The time now is 07:03 PM.