Raise amperage by sacrificing voltage?

Thread Starter


Joined Jan 29, 2012
I'm new on this forum and I need some help with an electrolysis project. I have a transformer that I plan on using. It puts out 90 volts AC. After I put a bridge rectifier on it to convert it to DC I need to, some how, raise the amperage. I know it can be done by lowering the voltage, I just don't know how. And Google has been no help. So how do I raise amperage by sacrificing voltage.

Hope you guys can help and hope to be spending a lot of time on this forum.


Joined Jul 9, 2011
You need a step-down DC to DC converter.

Depending on the current you need this will be an expensive project.

Can you give more details of required output current, output voltage and regulation requirements?

We used to build parallelable 5kW converters with 220V input, power factor correction and adjustable output (up to 300A at 16V), the whole thing working as a current cource or voltage source and with invertable polarity. They were bulky and expensive.

If you define exactly what you need it will be easier to think about a solution.


Joined Jul 1, 2008
Electrolysis is a broad term. Can you describe specifics? Are you electroplating, .. or the inverse,.. removing rust? Are you trying to make hydrogen?...
Any of the above?


Joined Feb 5, 2010
You could make multiple electrode sets and wire them in series so each unit would only drop 2 or 3 volts.

I posted this link a few days ago on another thread about the same subject.


Reading it could help you answer many different questions about the various methods available to you. You may not need to lower the voltage at all. Arrangements that let one change the voltage by increasing or decreasing the number of individual electrolysis units would be perfect for wind and solar uses that can be variable in power provided to work with.

Thread Starter


Joined Jan 29, 2012
I'm trying to make hydrogen. I don't have a lot of specifics about what I’m using or what I need. I'm using a transformer that I ripped out of an old amplifier a few years ago. It's 120v AC in. 45 or 90v AC out, depending on how it's wired. I have no idea what kind of amps it's putting out. I have no way to test it straight out and I haven't sad down and done the math to figure it out. But I will if you think it'll help. so basically I just need to get as many amps out of it as possible without going below 12 volts or 5 volts at the very minimum. I'm not really expecting too much out of it. It's just a little experiment I’m doing in my spare time.

Thread Starter


Joined Jan 29, 2012
Sorry guys. I was wrong about the voltage. It's got 3 leads. 2 yellow and one black. Yellow to yellow puts out 77 volts AV and black to yellow puts out 38 volts AC. The ohms when it's unplugged is 1.6. when it's plugged in it starts a .160 ohms and cycles down to zero the shoots back up to .160 and dose it again... no idea if that's relevant. So like I said, I have no idea what the watts or amps are. I will say it gave me a hell of a shock though. Anyway, any help would be much appreciated.


Joined Dec 26, 2010
You should not try to use a resistance meter on a powered circuit. Any readings you obtain are likely to be incorrect, and your meter is liable to be damaged.


Joined Nov 25, 2009

Electrolysis isn't a de facto equivalent to HHO and as it has been discussed not long ago, it is a legitimate source of hydrogen in small quantities.