Hello.
I am trying to make ironcore inductors from some old transformers. Some things are not clear to me:
Please check photos, where I marked areas of interest.
Photo 01:
1. Which parts can touch? (see picture). Can any off B's touch Frame A?
2. How many insulated gaps in core? One or two? Insulation between B3-B4 and B1-B2? or one insulated, one just glued?
3. If only one core gap needs is insulated, then I need make sure that another one is conductive? So i need to be careful so glue doesn't insulate that junction by accident?
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Photo 02:
4. Can I build just one coil former, and wind all wire on it like shown in picture? Or do I need to wind two like original transformer, and connect in series?
5. If one coil is fine, D or H gap should be insulated? Or both?
6. Is there rough rule of thumb how much inductance I could get, knowing that this was normal 220V transformer. I probably should try winding some windings with random wire, and measuring inductance, since wire thickness should not make big difference in calculating?
I am trying to make ironcore inductors from some old transformers. Some things are not clear to me:
Please check photos, where I marked areas of interest.
Photo 01:
2. How many insulated gaps in core? One or two? Insulation between B3-B4 and B1-B2? or one insulated, one just glued?
3. If only one core gap needs is insulated, then I need make sure that another one is conductive? So i need to be careful so glue doesn't insulate that junction by accident?
__________________________________________________________________________________________________________________________________________________________________________________
Photo 02:
4. Can I build just one coil former, and wind all wire on it like shown in picture? Or do I need to wind two like original transformer, and connect in series?
5. If one coil is fine, D or H gap should be insulated? Or both?
6. Is there rough rule of thumb how much inductance I could get, knowing that this was normal 220V transformer. I probably should try winding some windings with random wire, and measuring inductance, since wire thickness should not make big difference in calculating?
1. Yes
2. Two. Equal preferred.
3. N\A
4.Yes
5. Gap insert has to be dielectric, paper at very least
6. One needs to know dimensions for that. L=mu0*mu*4*Pi*1e-7*W^2*A/l, where mu=permeability W - turns' count A-core cross-section, l-mean magnetic length. But it's more complicated than that.
Just FYI
Check DC Choke Core Design Tool by Metglas, Inc. DCC.exe
Find core of a similar size and proceed from there
Google knows yet another free online calculator for a DC choke/inductor...
2. Two. Equal preferred.
3. N\A
4.Yes
5. Gap insert has to be dielectric, paper at very least
6. One needs to know dimensions for that. L=mu0*mu*4*Pi*1e-7*W^2*A/l, where mu=permeability W - turns' count A-core cross-section, l-mean magnetic length. But it's more complicated than that.
Just FYI
Check DC Choke Core Design Tool by Metglas, Inc. DCC.exe
Find core of a similar size and proceed from there
Google knows yet another free online calculator for a DC choke/inductor...
Wrt #1, there may be a benign level of flux circulating around the mounting ends, and A's - are all those pieces steel?
As an aside, even just butting or gluing the C-cores together causes a very small gap.
Assuming you want the choke to pass DC current, and have a certain level of inductance, and attenuate a certain incoming level of ripple voltage, do you have any tools or method to measure inductance for a given Vac across the choke, and a given Idc through the choke?
Did you keep the original winding/former - as that could make a good initial coil to play with.
As an aside, even just butting or gluing the C-cores together causes a very small gap.
Assuming you want the choke to pass DC current, and have a certain level of inductance, and attenuate a certain incoming level of ripple voltage, do you have any tools or method to measure inductance for a given Vac across the choke, and a given Idc through the choke?
Did you keep the original winding/former - as that could make a good initial coil to play with.
Hi. I also need to make C core 10-15mH coils of 4 pcs. It is Impossible to import because it costs me 1000usd tax and fees in Turkey. ( C core Jentzen Coils only Costs 300-400 USD plus 100usd shipping but taxes are 3 times more expensive! ) Can I make with toroidal cores maybe 100VA ones ?Any advice?