Filament Transformer Question ?

[HP8903B]

I have a 12.6V CT 2 Amp Filament transformer.

I want to use 6.3V to run one 6.3V tube, and the second 6.3V to run another 6.3V tube.
Each tube requires 1.8A.

If I use both 6.3V from the transformer, does each 6.3V handles 2A ?
Or each 6.3V can only handle 1A ?

 

[DUG]

Each 6.3V can handle 2A.

Or to put it another way:

If you put the two tube filaments in series you would need 12.6V @ 1.8A

Still OK

(but I would not recommend doing it that way)

OK?

 

[HP8903B]

Thank you

(but I would not recommend doing it that way)

You mean wire the 2 tubes in series ?

 

[cnpope]

Thank you



You mean wire the 2 tubes in series ?

As far as the current calculation is concerned, you could wire them in series. There is a possible concern that they might not divide the voltage equally. So connecting one of the tubes to one 6.3V winding, and the other to the other winding, would be better. But the basic answer is yes, the transformer could handle the load.

Chris

 

[HP8903B]

I understand.
Thank you

 

[Robert Kesh]

There is a possible concern that they might not divide the voltage equally.

For small differences a resistor in parallel with the heater that has the most voltage across it can remedy this. One at about 20 divided by voltage difference between the two in this case.

 

[DUG]

Filament loads will change slightly over time...perhaps they will track...perhaps not.

That is why I do not recommend it...but it could be done.