220-110v transformer question

[rotation]

Hi!
Someone asked me to find solution for hi's 110v/50w power transformer in drum machine. Here in SLovenia we have 220 v, so we need something to step down. Existing transformer has several taps, so i think the cheapest solution would be to make external 220 to 110v.
Is 50w enough, or i need more? Is toroid the smallest? We don't want to have another big box.
Thanks in advance!

 

[alk509]

[quote author="rotation"]i think the cheapest solution would be to make external 220 to 110v.[/quote]

220V... Ugh! Why can't we all just get along? :wink:

A separate transformer is a PITA. Don't give up on finding a replacement transformer... Measure out the taps and look around for something similar. Also check if the transformer has dual primaries.

Good luck!

Peace,
Al.

 

[rotation]

Thanks Al :thumb:
I already checked the primary. It's only one.
Of course i can find replacament transformer, but i'm not sure if it would affect surrounding circuitry. I never done this before...
If i decide to make external, is 50w enough, or i need more? Would you please explain this a little bit? I was told to buy at least 100w because the voltage decreases, but i'm not sure about it. Another strange thing (for me ) is 50w power consumption. The circuit doesn't seem that hungry...

 

[Boswell]

You don't need any more watts (strictly VA) just because you are stepping down the voltage and doubling the current. If the drum machine transformer is rated at 50W, you can use an external 50W step-down transformer, either a two-winding isolating type or a single-winding auto-transformer.

I would be amazed if the drum machine dissipated anything like 50W. It would get quite hot if it did.

 

[rotation]

Yes, i also don't think it could dissipate so much.
Thanks for clearing this out. I will make external to for using it also with other 110v gear.
Miha