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3 phase AC to DC

Started by malua mada! February 2, 2021
I am running 3 phase AC into a set of transformers, Y config,  and thence into bridge rectifiers . One leg of the output side of the transformers goes to the diodes. the other leg to the Y connection.
That Y connection gets warm. (why?)
Should it be connected to DC ground? 
 malua mada! wrote:

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> I am running 3 phase AC into a set of transformers, Y config, and thence into > bridge rectifiers . One leg of the output side of the transformers goes to the diodes. > the other leg to the Y connection. > That Y connection gets warm. (why?) >
** Have you linked the " + "and " - " of each bridge ? That is NOT how it is done. Google it. ..... Phil
On 2021-02-02, malua mada! <fritzo2ster@gmail.com> wrote:
> I am running 3 phase AC into a set of transformers, Y config, and > thence into bridge rectifiers . One leg of the output side of the > transformers goes to the diodes. the other leg to the Y connection. > That Y connection gets warm. (why?) > Should it be connected to DC ground?
The y connection should not get warm, is the connection there good? it takes 6 diodes for a threee phase rectifier which is not normally called a "bridge", that term is usally reserved for diamond-shaped arrangements that have input on two opposing corners and output on the other two. -- Jasen.
malua mada! <fritzo2ster@gmail.com> wrote:
> I am running 3 phase AC into a set of transformers, Y config, and thence into bridge rectifiers . One leg of the output side of the transformers goes to the diodes. the other leg to the Y connection. > That Y connection gets warm. (why?) > Should it be connected to DC ground?
The connection between this and that point is wrong.
Sorry I was not aware that the term "bridge" is reserved ... but I AM using 3 bridges.  The two AC inputs on each device are joined thus doubling up / paralleling (?)  each bridges' diodes. 
I could have done it with one and a half bridges (not doubling up on diode pairs) but why be stingy.
On 2021-02-03, malua mada! <fritzo2ster@gmail.com> wrote:
> > I AM using 3 bridges. The two AC inputs on each device are joined thus doubling up / paralleling (?) each bridges' diodes. > I could have done it with one and a half bridges (not doubling up on diode pairs) but why be stingy.
That should work perfwectly so long as the DC terminals all match up. The only reason I can think of for heat at the Y point is if the terminals are dirty or loose. -- Jasen.