Hi guys/gals,
I’m trying to build up a variac that was given to me. My grandfather was big into electronics and he had one he used for soldering and charging batteries quit a bit. I have a few questions about the build up, however. Let me give some details on the parts I have now and what I’m trying to achieve here.
The variable transformer I have is a 5 amp type 21. I robbed an old C.T. transformer out of a battery charger for the isolation transformer and have a 1000V 35A full wave bridge rectifier. I also have a 1000uf 50V cap for smoothing.
I planed on ordering a transformer that wasn’t a center tap, but found this one and have some questions about the wiring. The battery charger I robbed had a input switch for 6V 6A, 12V 2A, and 12V 6A.
On the primary side there’s a black, yellow, brown and red wire. If I put 120V on the black/red wires, I get 27V across each end of the transformer. With 120V on the black/brown 23V, black/yellow 16V. I’d assume that from the middle tap to each end would give me half the volts listed above. Does this mean this is a 120v to 24v transformer at around 8 amps? There’s a number on it (MS496 00) but I can’t find any info on it. I guess it’s sufficient for what I want to do, just not sure about the wiring on it.
It also had a half wave rectifier, but I want to use a full wave along with a 1000uf 50v cap. Will this change the output voltage? High output isn’t really a concern as I can adjust it with the variac.
I would like to have 2 120v outlets…one regulated and one that’s not. A DC output with a ground is in the plan also. I”ll post the schematic I had before I came across this transformer. I know how to wire it with a regular transformer, but this center tap throws me off, as I’m no electronic expert.
http://i1114.photobucket.com/albums/k523/3rror1/variac.jpb
Forget the LED on the DC side...it's in the wrong place as it should be right after the switch and be a AC light.
Can someone help me, or point me in the right direction here?
Thanks guys for any help!
Eric
I’m trying to build up a variac that was given to me. My grandfather was big into electronics and he had one he used for soldering and charging batteries quit a bit. I have a few questions about the build up, however. Let me give some details on the parts I have now and what I’m trying to achieve here.
The variable transformer I have is a 5 amp type 21. I robbed an old C.T. transformer out of a battery charger for the isolation transformer and have a 1000V 35A full wave bridge rectifier. I also have a 1000uf 50V cap for smoothing.
I planed on ordering a transformer that wasn’t a center tap, but found this one and have some questions about the wiring. The battery charger I robbed had a input switch for 6V 6A, 12V 2A, and 12V 6A.
On the primary side there’s a black, yellow, brown and red wire. If I put 120V on the black/red wires, I get 27V across each end of the transformer. With 120V on the black/brown 23V, black/yellow 16V. I’d assume that from the middle tap to each end would give me half the volts listed above. Does this mean this is a 120v to 24v transformer at around 8 amps? There’s a number on it (MS496 00) but I can’t find any info on it. I guess it’s sufficient for what I want to do, just not sure about the wiring on it.
It also had a half wave rectifier, but I want to use a full wave along with a 1000uf 50v cap. Will this change the output voltage? High output isn’t really a concern as I can adjust it with the variac.
I would like to have 2 120v outlets…one regulated and one that’s not. A DC output with a ground is in the plan also. I”ll post the schematic I had before I came across this transformer. I know how to wire it with a regular transformer, but this center tap throws me off, as I’m no electronic expert.
http://i1114.photobucket.com/albums/k523/3rror1/variac.jpb
Forget the LED on the DC side...it's in the wrong place as it should be right after the switch and be a AC light.
Can someone help me, or point me in the right direction here?
Thanks guys for any help!
Eric
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