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Ed_Dinning · 22nd Oct 2006, 7:24 pm

Hi Mike, the tricks you describe are equally valid on all types of transformer.
Multifilar windings are often used to ease handling of thick wires or to "fill" a layer without too much "build up"
Becaus eof the closed magnetic circuit on a toroid the 1/2 primaries can be wound opposite each other instead of on top. This may ease insulation requirements.
Mains primaries were often wound this way for 110/220 volt use by series parallel connection.

On thing to try is to plot the V/A curve of the core with a given number of turns. It should be a straight line up to the turns per volt figure you will use in practice. For Hi Fi audio use you should aim to work at about 1/2 the start of saturation level.

Ed

22nd Oct 2006, 7:24 pm	#17
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: Toroids as O/P trannies Hi Mike, the tricks you describe are equally valid on all types of transformer. Multifilar windings are often used to ease handling of thick wires or to "fill" a layer without too much "build up" Becaus eof the closed magnetic circuit on a toroid the 1/2 primaries can be wound opposite each other instead of on top. This may ease insulation requirements. Mains primaries were often wound this way for 110/220 volt use by series parallel connection. On thing to try is to plot the V/A curve of the core with a given number of turns. It should be a straight line up to the turns per volt figure you will use in practice. For Hi Fi audio use you should aim to work at about 1/2 the start of saturation level. Ed