What causes an uneven voltage output on a +/- supply...
This should be a no-brainer but I have tranny of 30VAC and voltage of 40VDC. No problem. But it is +5VDC to GND and -35VDC to GND.
Tranny to bridge then to a couple rows of caps. GND comes from AC GNC "down the middle of the caps...
This should be a no-brainer but I have tranny of 30VAC and voltage of 40VDC. No problem. But it is +5VDC to GND and -35VDC to GND.
Tranny to bridge then to a couple rows of caps. GND comes from AC GNC "down the middle of the caps...
GND has to come from a source of some kind, the capacitors do not work well as a voltage divider as you have found. It should go to the centre tap of your transformer. If you have none, you would have to do something like a voltage doubler arrangement or a supply splitter circuit afterwards.
How much current do you need this supply to provide?
How much current do you need this supply to provide?
I have no center tap...
Ah ha!
But I have made this 30VAC from two transformers of 15VAC... I guess I ought to connect the GND to the point where I connected the two trannys. Right?
Anyway, it would be nice to know the alternative.
A couple or three amps I reckon...
That would be plenty.
Thanks for the physics lesson!
Ah ha!
But I have made this 30VAC from two transformers of 15VAC... I guess I ought to connect the GND to the point where I connected the two trannys. Right?
Anyway, it would be nice to know the alternative.
A couple or three amps I reckon...
That would be plenty.
Thanks for the physics lesson!
From where the two transformers are connected, I ran a wire to ground. DC voltage is now +20 and -32 after the caps and snubbers.
What gives?
What gives?
No, I haven't applied a load. The measurements are unloaded. 1K 2 watt OK? To each side and GND and then test + to -?
It works with a load. Each side with a R390 2 w and the voltage is ~20 on each side... within a few mV,
How come?
How come?
you should use a separate diode bridge for each transformer and then tie together the + output of one bridge with - ouput of the other. This'll be your gnd point.
il your transformers ac voltage are the same, the dc will be the same too.
il your transformers ac voltage are the same, the dc will be the same too.
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