fallout

Quick power transformer ? (Gyraf Pultec)
« on: August 12, 2004, 05:54:45 PM »
I noticed on the PDF file for the layout it says for 110Vac use:

Trafo 1: 110:12V 1.5A
Trafo 2: 110:6V 1.5A

Is this correct? Or should it be 2 110:12V transformers?

Thanks!

-Jay


Kev

Quick power transformer ? (Gyraf Pultec)
« Reply #1 on: August 12, 2004, 06:17:12 PM »
NO

think about it    :wink:

the circuit requires  220ac.
You have 110 at the wall.
The second trafo at 6 volts in will step up to 220 when 12v is applied to the input.

DO NOT use a 6v - 110v trafo
... as it will saturate when it goes up past say 130/140v .... I'm guessing here.

It must be a 220 v trafo to handle the voltage.


There are very few errors ... if any by now .... in all of Jakob's paper work.
Please read carefuly.
... then say thanks to Jakob.
Kev
DIY Factory

fallout

Quick power transformer ? (Gyraf Pultec)
« Reply #2 on: August 12, 2004, 06:34:59 PM »
Great Kev, thanks.. Correct me if i'm wrong...

I'd get 2 110:12 power transformers

and wire the primaries on the 2nd transformer in series to get the 220Vac necessary (the transformers i'm looking at work at 110 and 220 Vac)? I was confused because Jakob's PDF file specifies a 110:6V transformer..

Thanks
-Jay

ChuckD

Quick power transformer ? (Gyraf Pultec)
« Reply #3 on: August 12, 2004, 07:00:32 PM »
Alrighty

I had posted a concern I had with my completed G-Pultec on the hot transformers.

Here are the ones I used: Digikey

TE62062-ND   12 VAC  2.082 amps   (115 volt  torriod)
237-1046-ND   6.3 VAC 2.0 amps    (115 volt  split pack)

Look at the picture (see Pultec META thread)

The 12V  one is the Trafo 1 and the 6.3V is trafo 2. My problem was that Trafo 1 was getting really hot!
It was suggested to try and use a bigger Transformer instead.


As far as the spec goes I think it is correct. 110 volts in 12 volts out then feed 12V into the 6.3 volt side and get 220 Volts out.  Makes sense?
Anyway I also measured 220volts just to be sure before putting my Tube in there.

I am going to try a bigger Trafo 1 and post the results.

ChuckD

Quick power transformer ? (Gyraf Pultec)
« Reply #4 on: August 12, 2004, 07:03:56 PM »
I'm probably going to try TE62082-ND and see if that stays a little cooler.
Unless someone can suggest a better solution.


-ChuckD

fallout

Quick power transformer ? (Gyraf Pultec)
« Reply #5 on: August 12, 2004, 07:17:03 PM »
I'm looking at using the same torroids.. However, shouldnt the primary of the 2nd transformer be wired in series to get the 220V? in 110 operation wouldnt it saturate as Kev suggested?

-Jay

ChuckD

Quick power transformer ? (Gyraf Pultec)
« Reply #6 on: August 12, 2004, 07:19:29 PM »
I pretty sure I wired it for 110 operation in both cases.
Look at the picture and you should be able to tell what leads I connected then you can look and the trabforer specs to figure that out.

I'll do the same,

-ChuckD

fallout

Quick power transformer ? (Gyraf Pultec)
« Reply #7 on: August 12, 2004, 07:34:19 PM »
I cant really tell by the pics.. Why didnt you use 2 of the TE62063-ND's? Why the PCB mount transformer?

-Jay

AudioJunkie

Quick power transformer ? (Gyraf Pultec)
« Reply #8 on: August 12, 2004, 08:52:15 PM »
110:12 (first trafo) Gives you 12 volts into the second transformer.

110:6 (second trafo)fives you 18.3333...

12 (from the first) X 18.3333...=220

If you wire the second trafo for 220, then 220:6 gives you 36.6666...
12 X 36.8888 = 440.

Wire the second trafo for 110.

I suppose you could get a 220:12 trafo and that would preserve the multiplication.
Someone feel free to correct me if i'm wrong.  

Daniel

fallout

Quick power transformer ? (Gyraf Pultec)
« Reply #9 on: August 12, 2004, 09:21:12 PM »
Now i'm really confused! LOL...

I couldnt use 2 110:12V transformers?

Wire the 1st as usual 110:12v and the 2nd 12v:220?

-Jay


AudioJunkie

Quick power transformer ? (Gyraf Pultec)
« Reply #10 on: August 12, 2004, 09:51:53 PM »
no, you would just get 110:12 and then back 12:110.

The first transformer goes from mains to the 12V (in this case 110:12).

Then you have to get from 12V to 220V.  In which case you need either 6:110 or 12:220 (only the other way around, since you're using step down transformers backwards)

The ratio 110:6 gives you a multiple of 18 1/3.  So if you're feeding 12V into that, you get 220VAC.

If you use 110:12, you only get a multiple of 9 1/6, which would only get you back to 110.

I've never been great at describing things verbally, maybe I should try graphically.

Daniel

AudioJunkie

Quick power transformer ? (Gyraf Pultec)
« Reply #11 on: August 12, 2004, 09:55:38 PM »
Crap.  

I didn't read your messages quite right.  Serves me right for trying to be helpful after being awake for 30 hours.  Ignore my last message.

YES, you could use 220:12.  But not 110:12.  (Somehow I miss the part about wiring it for 220 :-)

Therefore you get 110:12 and then 12:220.  

Okay, time for me to crawl into bed.

Later,
Daniel


 

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