- Joined May 18, 2021
So I just received a transformer I ordered on Amazon to rectify for DC rails to drive a class B push-pull amplifier and I thought it was just a single primary winding when I ordered it, but it turns out that it has 2 primary windings that are center tapped. The box says 115V/230V, and the primary wires are colored black/yellow/red, but according to a customer review on Amazon the red is the center tap, not the yellow. This isn't the first rectifier I've built, but it's the first time I've dealt with multiple primaries. So my question is... for 115V do I connect the hot & neutral mains to one primary winding and the center tap, or do I connect across both windings and leave the center tap open? And can the primaries be wired in parallel to get more power out of it by connecting both outside primary wires to hot and the center tap to neutral and will I see more voltage in the secondary or will it just pull more current and dissipate more wattage? I suspect that by using both primary windings in that fashion, the voltage will double in the primary, but the turns ratio will go from 5:1 to 10:1 and so the secondary voltage will remain at 24. Am I wrong? Like I say, I've never encountered a transformer with multiple primaries, so I've got no idea about how different configurations of connections to the mains will behave. I've checked out the datasheet and it's full of clerical mistakes, so I'm not trusting anything the datasheet contains, but I'm attaching it and a link to the manufacturer's page for the product anyway.
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