Diode Bridge & Washing Soda Rust Removal

[ratchetbender]

I have a big job of parts rust removal. Thought I might as well gather up some selected salvage components for the job. I don't care to burn up any battery chargers.

I'm using an 875 watt 24V AC transformer.

What will these giant diode's resistance do to voltage drop in this setup.

Will there be any power left ?
Suggestions ?

 

[Mike Folks]

Two of them,look to be SCR's,(Silicon Controlled Rectifiers),see that little wire coming out of the insulator? That's where power turns the SCR off and on. When I built heat sink assemblies using these types, an Aluminum heat sink with conductive grease transferred the heat from the components to the heat sinks.

 

[Bert_]

Assuming their silicon you will have .7 volts drop across each junction.

 

[dogdog]

Might be over kill and not necessary... I Have used a 20Amp 24V on rust removal... it works.. but it never draw more than 10AMP... really...

Also you have to consider those ripple currents it works against you

 

[ratchetbender]

I have many of these without the "little wire". I assume not to use them.
Will a setup like this work ?

 

[Sevenhills1952]

Power diodes should be mounted on heat sinks. One large sink would be ok but you would have to use insulators.
If you have two 12v batteries and two chargers that would be easiest. Just series two batteries for 24vdc, charger on each battery.
I like these bridges better. 1/4" lugs, one bolt onto a heat sink with some heat compound. If you want to use that transformer. 24v(rms), less the voltage drop still get about 30vdc out of it.

Sent from my SM-S320VL using Tapatalk

 

[Shiftless]

You don’t need 24 volts.
One 12 volt battery will work fine. I would put a fuse in the circuit to protect the set up against accidental shorts. Put a battery charger across the terminals to keep the battery charged up.

Seems to me it would be simpler to just get an old battery charger maybe 10 amps and go with that. Modern solid state chargers might not work with an electrolysis system. But they will if you put a battery into the circuit.

 

[Mike Folks]

SCR's are fast acting switches,the little wire or stud on top of the ceramic, turns on or off the switch part. Usually many capacitors and chokes filter out the ripple output.

 

[RPH]

Read the numbers on the devices. Those are stud mounted units that need to mount to something conductive. The early induction systems were big users of them. There was times I had forty of the in parallel to get the required current. The wire out the top doesn’t mean it’s a gate lead. Take pics of the devices and post them. Will try to help.