# Toroidal transfomer help

Discussion in 'General Electronics Discussion' started by onpiopah, Feb 26, 2013.

1. ### onpiopah

7
0
Jan 18, 2012
Hi I have a Toroidal transformer and the only information I have is

230v 120VAC 30vac x 2.

I understand the 230V, and the 30vac, does this mean it will produce 30 volts AC from each of the 2 secondary wires out.

But what does the 120vac mean?

It is from a Cambridge A1 Mk3 amplifier.

2. ### duke37

5,364
771
Jan 9, 2011
A picture may help.

Many amplifires have transformers that can be driven from either 230V or 125V AC by using a tap on the input winding or two windings which can be connected in series (230V) or parallel (125V) for use in different countries.

There seems to be two indepedent output windings at 30V AC. These will be used to supply a positive and negative voltage for the amplifier.

You could try to find a circuit diagram.

3. ### onpiopah

7
0
Jan 18, 2012
thanks duke37, i did assume that this meant it could be driven by either 230 or 120, but i just wanted to make sure i did not assume to much which would have confused me at a later date.

4. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,496
2,837
Jan 21, 2010
Or it's 120VA (not 120VAC)

5. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,496
2,837
Jan 21, 2010
How many wires does it have coming out? If only 4, then it's 230 -> 30. If more than 4 wires there are several options.

It is quite unlikely that unless there are 2 primary windings (4 primary wires) that the transformer is designed for 2 different input voltages.

6. ### onpiopah

7
0
Jan 18, 2012
its only the 4 wires

7. ### duke37

5,364
771
Jan 9, 2011
There must be more than four wires. Two for the primary and three or four for the secondarys. The primary wires will be opposite to the secondaries and thinner wire.

Give us the label again and a photo also.