I'm just getting started in electronics. I've done some repairs on a number of battery chargers and welders, and misc other projects, but I'm at the stage where I have way more questions about most things, than anything else. I don't have the money to drop on a bench full of equipment, so I'm having to scrounge and build, as I can. I looking for a deal on a scope, but one hasn't come way way, yet.
I came across the guts of a 'Variac' being used to control a bank of ceiling fans. It is a Luxtrol WBD750, (0-125V, 750W, 6. 25A). I was looking at buying a Variac when I was given the Luxtrol, so I changed directions and am, instead, building one.
I have it in a prototype case with both analog and digital gauges, and a variety of connections for output voltage. I'm currently looking for a suitable 1:1 transformer to place between it and the wall voltage, to create an isolation transformer.
I'm a bit cramped for bench space, so I got to thinking about also using this as a DC power supply. I couldn't come up with a reason not to combine the two power supplies into a single unit, but if there is, please let me know what I missed.
I have a rectifier, (1600V, 100A), I didn't use for a welder repair. I figured that would certainly handle anything I put through it, but I'm not sure how to approach calculating the capacitor size for smoothing the rectifier output.
I have done a lot of research on spec'ing a cap for a fixed output, but haven't actually done one, yet. From what I learned, it comes down to formula math based on several data points derived from the application. Seems straight forward.
Something I discovered in my research, was a number of different formulas so, one challenge may be choosing the 'right' formula! (I figured I do calcs with several, and see how close their relative outcomes turn out.)
Regarding the variable power supply, do I use what would be maximum output from the power supply to calc the cap size?
(I wouldn't ever drive anything at a full 6.35A @ 125VAC, but I assume designing at max would give me 'headroom', and adequate function.)
The other question I have is about inductors. Some of the devices I have repaired, (battery chargers, welders), have had induction coils, in addition to capacitors, for smoothing the rectifier output. Do I need to plan on including an inductor?
Any help, or clarifications, (if I'm heading in the wrong direction with some aspect), will be greatly apppreciated.
Thanks, in advance.
GeoD
I came across the guts of a 'Variac' being used to control a bank of ceiling fans. It is a Luxtrol WBD750, (0-125V, 750W, 6. 25A). I was looking at buying a Variac when I was given the Luxtrol, so I changed directions and am, instead, building one.
I have it in a prototype case with both analog and digital gauges, and a variety of connections for output voltage. I'm currently looking for a suitable 1:1 transformer to place between it and the wall voltage, to create an isolation transformer.
I'm a bit cramped for bench space, so I got to thinking about also using this as a DC power supply. I couldn't come up with a reason not to combine the two power supplies into a single unit, but if there is, please let me know what I missed.
I have a rectifier, (1600V, 100A), I didn't use for a welder repair. I figured that would certainly handle anything I put through it, but I'm not sure how to approach calculating the capacitor size for smoothing the rectifier output.
I have done a lot of research on spec'ing a cap for a fixed output, but haven't actually done one, yet. From what I learned, it comes down to formula math based on several data points derived from the application. Seems straight forward.
Something I discovered in my research, was a number of different formulas so, one challenge may be choosing the 'right' formula! (I figured I do calcs with several, and see how close their relative outcomes turn out.)
Regarding the variable power supply, do I use what would be maximum output from the power supply to calc the cap size?
(I wouldn't ever drive anything at a full 6.35A @ 125VAC, but I assume designing at max would give me 'headroom', and adequate function.)
The other question I have is about inductors. Some of the devices I have repaired, (battery chargers, welders), have had induction coils, in addition to capacitors, for smoothing the rectifier output. Do I need to plan on including an inductor?
Any help, or clarifications, (if I'm heading in the wrong direction with some aspect), will be greatly apppreciated.
Thanks, in advance.
GeoD