Beginning of my Reduction

xavhan · 2631

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Offline xavhan

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on: February 07, 2015, 01:53:31 AM
Hey guys,
I just got my Reduction Kit this week and i began to build it but I have some question about the voltages of the power transformer.

I live in France so i got the 240V PT5 transformer

I can read on it that i should expect :
- 240V between the 1 and 2 pins
- 9V between 4 & 5
- 135V between 6 & 7

I mesured 220V in my wall outlet

so if my calculations are good i should get
- 220V between 1 & 2
- 8,25V between 4 & 5
- 123,75V between 6 & 7

When i do my measures on the real thing i get :
- 211V between 1 & 2
- 8.75V between 4 & 5
- 125V between 6 & 7

The manuel says that i should get
- 9,7V between 4 & 5
- 140V between 6 & 7


I am a bit troubled because the gap is quite important :
- -9,8% gap with expected value (4 & 5)
- -10,7% gap with expected value (6 & 7)

Did i do something wrong? Is this gap important ? Can i continue my building ?

Thanks by advance, I'll keep you posted on the realisation.



Online Paul Birkeland

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Reply #1 on: February 07, 2015, 05:43:17 AM
Terminals 1 & 2 should receive your line voltage.  If you have 220V at the wall and 211V between those terminals, there's a funky joint somewhere or the power cord has a loose connection.

The amp will function well on 220V, I'd take the time to see where things aren't getting through.

What AC voltage do you have between N and L on the IEC inlet jack?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man