Transformer insulateing tape?
in [Design]
|
Prev: Capacitor discharge probes
Next: makes no sense to me
From: Hammy on 19 Jun 2010 12:50 What kind of tape can you use for insulation between primary to secondary of flyback transformer. I know mass produced professional designs use a 3M specialty tape. What I'm looking for is a tape I could pick up at Staples or some office supply store or hardware store. The vinyl electrical tape I can find is only rated for 600V and 80C MAX TEMP. Is there a commonly available tape that is good for higher temp and offers higher insulation? I've read of people using a mylar tape is there a brand name ,type anyone could recommend? This is for a 90 - 140Vac input flyback.
From: qrk on 19 Jun 2010 13:25 On Sat, 19 Jun 2010 12:50:40 -0400, Hammy <spam(a)spam.com> wrote: > >What kind of tape can you use for insulation between primary to >secondary of flyback transformer. I know mass produced professional >designs use a 3M specialty tape. What I'm looking for is a tape I >could pick up at Staples or some office supply store or hardware >store. > >The vinyl electrical tape I can find is only rated for 600V and 80C >MAX TEMP. > >Is there a commonly available tape that is good for higher temp and >offers higher insulation? I've read of people using a mylar tape is >there a brand name ,type anyone could recommend? > >This is for a 90 - 140Vac input flyback. I like using 3M #56 polyester tape. I think you can get it from Newark, but you'll need to cut it yourself to proper width. If this is for commercial use, there are companies out there that will precision slit the tape for you. See if you can find some China knockoff tape. http://mws9.3m.com/mws/mediawebserver.dyn?6666660Zjcf6lVs6EVs666vV8COrrrrQ- -- Mark
From: Archimedes' Lever on 19 Jun 2010 14:53 On Sat, 19 Jun 2010 12:50:40 -0400, Hammy <spam(a)spam.com> wrote: > >What kind of tape can you use for insulation between primary to >secondary of flyback transformer. I know mass produced professional >designs use a 3M specialty tape. What I'm looking for is a tape I >could pick up at Staples or some office supply store or hardware >store. > >The vinyl electrical tape I can find is only rated for 600V and 80C >MAX TEMP. > >Is there a commonly available tape that is good for higher temp and >offers higher insulation? I've read of people using a mylar tape is >there a brand name ,type anyone could recommend? > >This is for a 90 - 140Vac input flyback. 3M transformer tape. Fish paper. http://export.farnell.com/3m/f1350-12mm/tape-polyester-12mmx66m/dp/726977 http://export.farnell.com/3m/f1350-25mm/tape-polyester-25mmx66m/dp/753014 http://export.farnell.com/3m/1350-1-19mm/tape-polyester-19mmx66m/dp/75300 That is the product line. There are actually several vendors for that 3M tape, and even other makers, but 3M seems to be the most widely used by the industry. You should utilize a slightly wider tape than the bobbin spool width. (about 40 mils) and you should never wind all the way to the bobbin face with each layer of wire. There should be several wire widths for fine wire. Larger wire will not likely give wire insulation issues because of the few number of turns. Never place more than about 150 turns per layer with fine wire (no random spool fills). Without insulation between turn 151 (approx) and the starting series of turns, the voltage difference can/will cause a breach of the insulation and fail the xformer. Finally vacuum impregnation with on of these if high repeatability and reliability are desired: http://www.dolphs.com/pdfs/Dol_VarnishsResin_chart.pdf AC-43 is a common choice. It boils in a vacuum, so you have to bring it up slowly until that stops (it will eventually), then you can bring it up to nearly a full (industrially speaking) vacuum. Then bake them out. (you should bake at 60C for about a half hour before impregnation as well to eradicate water.
From: Archimedes' Lever on 19 Jun 2010 14:57 On Sat, 19 Jun 2010 10:25:34 -0700, qrk <SpamTrap(a)spam.net> wrote: > I think you can get it from >Newark, but you'll need to cut it yourself to proper width It is very easy to find a vendor that will slit custom widths of that tape. They buy it in VERY wide rolls just for that purpose.
From: Martin Riddle on 19 Jun 2010 15:00
"Hammy" <spam(a)spam.com> wrote in message news:mrsp16186ug87255qercqsp34jm20hr0a0(a)4ax.com... > > What kind of tape can you use for insulation between primary to > secondary of flyback transformer. I know mass produced professional > designs use a 3M specialty tape. What I'm looking for is a tape I > could pick up at Staples or some office supply store or hardware > store. > > The vinyl electrical tape I can find is only rated for 600V and 80C > MAX TEMP. > > Is there a commonly available tape that is good for higher temp and > offers higher insulation? I've read of people using a mylar tape is > there a brand name ,type anyone could recommend? > > This is for a 90 - 140Vac input flyback. I think Larkin mention http://www.tapecase.com/ , seems reasonable for small qty. Cheers |