I'm trying to measure the secondary voltage output of a reclaimed transformer. There are 5 wires: 2 red. 2 yellow, 1, black.
Black + either Red gives me 11.4
Black + either Yellow gives me 0.
What am I doing wrong?
Black + either Red gives me 11.4
Black + either Yellow gives me 0.
What am I doing wrong?
The black may be a center tap for the red winding.
So you may have:
winding #1: red - black - red
winding #2: yellow - yellow
So you may have:
winding #1: red - black - red
winding #2: yellow - yellow
Well, good to know.
Then you know what the secondaries are now.
You do understand that there are two isolated secondaries?
See post #2.
Then you know what the secondaries are now.
You do understand that there are two isolated secondaries?
See post #2.
I guess. But I don't understand much about it. The transformer came from an amplifier. I assume the 25v drives the chip and the 12v supplies everything else, the pre-amp, the LEDs etc . . .
Disconnect it from the mains.
Measure DC resistance, know which are isolated windings as a starting point.
Could be something like black is a centre tap of the red pair, yellows are another winding.
Measure DC resistance, know which are isolated windings as a starting point.
Could be something like black is a centre tap of the red pair, yellows are another winding.
There is always a capacitive coupling betwin windings, so if you have a modern multimeter the current needed to have a reading is so low you will have a value from any point to any point.
Put a '' medium value '' resistor ( 22K ) across the voltmeter an start measuring again.
Put a '' medium value '' resistor ( 22K ) across the voltmeter an start measuring again.