Toroidal Transformer replacement

Hi all,

I would like to replace a toroidal transformer with Pri 230v / Sec 17.5v - 0 - 17.5v and 8.5 V - 8.5V (5wires). I haven't found anything similar with the 0v center tap.
So i was thinking about to use this one:
30W / 30VA R-Core Transformer PRI 115V/230V 50/60Hz SEC 9V+ 9V / 18V + 18V | eBay

My theory is i need to connect always wire 1 from each color together to have the 0v and the second wire for each voltage as the positive.
But because both sides of the coil have the same color, i will never know which one i use as 0v and which one as positive... do you think this will matter?

Thanks,
Thomas
 
Hi all,

I would like to replace a toroidal transformer with Pri 230v / Sec 17.5v - 0 - 17.5v and 8.5 V - 8.5V (5wires). I haven't found anything similar with the 0v center tap.
So i was thinking about to use this one:
30W / 30VA R-Core Transformer PRI 115V/230V 50/60Hz SEC 9V+ 9V / 18V + 18V | eBay

My theory is i need to connect always wire 1 from each color together to have the 0v and the second wire for each voltage as the positive.
But because both sides of the coil have the same color, i will never know which one i use as 0v and which one as positive... do you think this will matter?

Thanks,
Thomas

Yes, how you connect the secondaries does matter. You will have to do some testing to figure out which way to connect the secondaries. Look up transformer polarity testing. You will need a voltmeter.
 
You could ask at Toroidy.pl. I'm not sure how much they will charge for a custom order, buy since they are a small family business I don't think it will be much more than their standard prices. Quality is top notch, but you maybe have to wait a while for it, especially given covid.
 
Yes! Toroidy is a great option. I know they have a hard time keeping up right now due to being a small business, so you might have to wait a little. But they can most certainly get you what you need, pretty cheap and with great quality.
 

Thanks, but this one is to tall.. it needs to fit into a Rack unit :-(
I have ordered the custom mad Toroidal.. it seems to be the best solution.