Transformer insulateing tape?
in [Design]
|
Prev: Capacitor discharge probes
Next: makes no sense to me
From: Hammy on 19 Jun 2010 19:18 On Sat, 19 Jun 2010 22:47:52 +0000 (UTC), Cydrome Leader <presence(a)MUNGEpanix.com> wrote: >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. > >are you making one transformer or many, and if so, are you using a coil >form? Just one. I'm using an ETD29 core with Bobbin. I've made several transformers for LVDC less then 50Vrms.This is my first transformer from scratch for a line powered supply. I usually just buy or get samples from places like coil craft, but I want a multiple output flyback 50W small light weight and I've got this down too fitting into a 5" x 3" x2.2" in enclosure. I know I could buy one for $50 to 100 plus but that's no fun;-) I will be the only one using it. Its main purpose is to save bench space and to save me the hassle of having to continually dig out 317's 7812 or 7805's when I'm working on something that requires multiple voltages. So its not going to be tested for EMC compliance (but I do have a line filter) or Hi Pot tested etc. I originally did it up to operate of my Bench top PSU with an EFD20 core/ bobbin set (for 24W ) but I want to be able to eliminate the larger Bench top PSU so I don't have so much clutter on the bench. Eventually I'll get around to building a half decent sized bench, but I just finished installing and painting seven new interior doors. That's my renovating fun for a couple of months anyway's. ;-)
From: Jim Thompson on 19 Jun 2010 19:30 On Sat, 19 Jun 2010 19:18:52 -0400, Hammy <spam(a)spam.com> wrote: >On Sat, 19 Jun 2010 22:47:52 +0000 (UTC), Cydrome Leader ><presence(a)MUNGEpanix.com> wrote: > >>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. >> >>are you making one transformer or many, and if so, are you using a coil >>form? > >Just one. I'm using an ETD29 core with Bobbin. I've made several >transformers for LVDC less then 50Vrms.This is my first transformer >from scratch for a line powered supply. I usually just buy or get >samples from places like coil craft, but I want a multiple output >flyback 50W small light weight and I've got this down too fitting into >a 5" x 3" x2.2" in enclosure. I know I could buy one for $50 to 100 >plus but that's no fun;-) > > I will be the only one using it. Its main purpose is to save bench >space and to save me the hassle of having to continually dig out 317's >7812 or 7805's when I'm working on something that requires multiple >voltages. > >So its not going to be tested for EMC compliance (but I do have a line >filter) or Hi Pot tested etc. > >I originally did it up to operate of my Bench top PSU with an EFD20 >core/ bobbin set (for 24W ) but I want to be able to eliminate the >larger Bench top PSU so I don't have so much clutter on the bench. > >Eventually I'll get around to building a half decent sized bench, but >I just finished installing and painting seven new interior doors. >That's my renovating fun for a couple of months anyway's. ;-) Solid-core door plus off-the-shelf metal leg assemblies is what I did. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | Where is Joe McCarthy when you need him ??
From: Archimedes' Lever on 19 Jun 2010 19:33 On Sat, 19 Jun 2010 19:18:52 -0400, Hammy <spam(a)spam.com> wrote: >On Sat, 19 Jun 2010 22:47:52 +0000 (UTC), Cydrome Leader ><presence(a)MUNGEpanix.com> wrote: > >>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. >> >>are you making one transformer or many, and if so, are you using a coil >>form? > >Just one. I'm using an ETD29 core with Bobbin. I've made several >transformers for LVDC less then 50Vrms.This is my first transformer >from scratch for a line powered supply. I usually just buy or get >samples from places like coil craft, but I want a multiple output >flyback 50W small light weight and I've got this down too fitting into >a 5" x 3" x2.2" in enclosure. I know I could buy one for $50 to 100 >plus but that's no fun;-) > > I will be the only one using it. Its main purpose is to save bench >space and to save me the hassle of having to continually dig out 317's >7812 or 7805's when I'm working on something that requires multiple >voltages. > >So its not going to be tested for EMC compliance (but I do have a line >filter) or Hi Pot tested etc. > >I originally did it up to operate of my Bench top PSU with an EFD20 >core/ bobbin set (for 24W ) but I want to be able to eliminate the >larger Bench top PSU so I don't have so much clutter on the bench. > >Eventually I'll get around to building a half decent sized bench, but >I just finished installing and painting seven new interior doors. >That's my renovating fun for a couple of months anyway's. ;-) Primary turns, wire size desired Secondary voltage and consumption level desired so that the secondary wire size can be determined/optimized. Form factor Post that.
From: Hammy on 19 Jun 2010 19:40 On Sat, 19 Jun 2010 16:30:04 -0700, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: [ snip] >Solid-core door plus off-the-shelf metal leg assemblies is what I did. > > ...Jim Thompson I just got some hollow mdf doors, I kept my pine jambs I refinished them last year they turned out nice. They actually look really nice after two coats of off-white semi gloss. They contrast well with the oak trim and pine jambs. I thought I might have made a mistake in not getting pine or oak doors $$ but it turned out well. There's enough wood in my house as it is.:-) I cant complain for $250 after all is said and done.
From: Hammy on 19 Jun 2010 20:03
On Sat, 19 Jun 2010 16:33:56 -0700, Archimedes' Lever <OneBigLever(a)InfiniteSeries.Org> wrote: > > Primary turns, wire size desired > Secondary voltage and consumption level desired so that the secondary >wire size can be determined/optimized. > > Form factor > > Post that. Primary inductance 300uH, Dmax 0.4, switching frequency 60kHz +/- 10% Operateing mode (if it isnt already obvious) DCM. N= 6 NP= 56 Gap 1mm I used a current density of 5A/MM2 for the primary resulting in conductor area of 0.181 mm2 or larger I plan on useing 3x 30AWG for the primary. Output voltages AC stacked +12 and +5 both at 2A countinous each. Both at 3.55Arms the 5V winding will also carry the upper 12V load current. Stacked windings translate to 9 turns 1.375 volts per turn. The five volts is regulated. I used a current density of 6A/MM2 (few turns) conductor area for the +12 is 0.592 mm2 twice that for the plus 5. Negative output voltages -12 and -5 both at 0.6A countinous each. Same winding startegy as above and turns rms current 1.06A |