Hi all.
I have toroid power transformer (220v primary, and 2x19/5.79A secondary), and I'm getting some funny voltage readings at secondary, which I cannot understand. Pls help.
Secondary has 4 wires, two black and two blue. One black and one blue are labeled with (1) label, other two are not labeled.
There is sticker on trafo, saying:
(black1/blue1 19V/5.79A )
(black/blue 19V/5.79A )
So I concluded, that pair labeled with (1) is one secondary, and the other without label is another secondary. And I connected blue (1) with black (no label), and that was to be my middle, zero.
Measuring secondaries gives me 21.8V twice, so I got 2x 21.8V secondary, which is fine.
But measuring secondary zero against mains ground shows 59.5V AC. So my zero is shifted by 59.5V. And other two rails from secondary give me 42.5V and 76.5V.
Besides that zero is shifted, measuring secondaries against zero mains gives me 17V difference (shifted by 59.5V), while measuring secondaries against their own middle point gives me 21.8V on secondaries. Why is this?
Why are voltages shifted against mains ground? Is this normal? Or did I connect wires incorrectly? How to connect it properly, so that secondary middle is same as mains zero? Do I need to connect secondary middle to mains ground, to force it to ground's zero? Pls help.
thnx
I have toroid power transformer (220v primary, and 2x19/5.79A secondary), and I'm getting some funny voltage readings at secondary, which I cannot understand. Pls help.
Secondary has 4 wires, two black and two blue. One black and one blue are labeled with (1) label, other two are not labeled.
There is sticker on trafo, saying:
(black1/blue1 19V/5.79A )
(black/blue 19V/5.79A )
So I concluded, that pair labeled with (1) is one secondary, and the other without label is another secondary. And I connected blue (1) with black (no label), and that was to be my middle, zero.
Measuring secondaries gives me 21.8V twice, so I got 2x 21.8V secondary, which is fine.
But measuring secondary zero against mains ground shows 59.5V AC. So my zero is shifted by 59.5V. And other two rails from secondary give me 42.5V and 76.5V.
Besides that zero is shifted, measuring secondaries against zero mains gives me 17V difference (shifted by 59.5V), while measuring secondaries against their own middle point gives me 21.8V on secondaries. Why is this?
Why are voltages shifted against mains ground? Is this normal? Or did I connect wires incorrectly? How to connect it properly, so that secondary middle is same as mains zero? Do I need to connect secondary middle to mains ground, to force it to ground's zero? Pls help.
thnx