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Connect two transformers in parallel? Answered

Hi! I have a question in case someone can help me.

I need an AC/AC converter from 120V to 12V for a halogen lamp. The required output is 210W, but I can't find a big enough transformer for this. Is it possible to connect two, 105W output transformers in parallel in order to achieve the desired 210W?

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iceng

Best Answer 11 months ago

Just saying, I have successfully mixed identical transformers and a 24V 4A in parallel with a 24V 2A...

The rule is go ahead and parallel two transformers JUST make sure they are in phase otherwise it will be a double short circuit..

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seandogue

11 months ago

As I recall it's not recommended to apply parallel transformers for a single load (you could wire up two identical transformers to power different loads), but it's been a while so I'm not positive of my claim.

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steveastroukseandogue

Answer 11 months ago

...or "Without advanced knowledge and identical transformers, don't"

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JuanC368

11 months ago

Thanks for all the help. It seems like it's possible, it's just a matter of making sure they're in phase as iceng said.

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steveastroukJuanC368

Answer 11 months ago

No, its a matter of making sure they are IDENTICAL, or adding resistors to break the current loops.

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icengsteveastrouk

Answer 11 months ago

Yes, If the magnetizing current is different as in the iron laminations being different, I do believe there would be a phase shift in the secondaries and that recirculating 12v lamp with the clip removed would really light up..

I'm still trying to find the video of that experiment showing no recirculating current...

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Jack A Lopez

11 months ago

Does it have to be 12 volts AC?

I mean if the load is just the filament in a big halogen lamp, it might be just as happy with 12 volts DC, supplied by something that is capable of giving 17.5 amperes of current, or whatever it is.

I mean, that's the number I get when I divide 210 watts, by 12 volts.

A car battery might work, preferably one that is attached to a car, because 17.5 A would drain the battery in a matter of hours, without the car's engine to recharge it.