# Transformer replacement

J

#### Jack// ani

Jan 1, 1970
0
Can I use 12V, 2amp centre tapped transformer in place of a 24V/2amp. I
will not use the tapped wire, so I'll get 24volts across its two
ends.

TIA

C

#### Chris

Jan 1, 1970
0
Jack// ani said:
Can I use 12V, 2amp centre tapped transformer in place of a 24V/2amp. I
will not use the tapped wire, so I'll get 24volts across its two
ends.

TIA

Nope. The center tap provides a voltage tap halfway between the two
legs, like this (view in fixed font or Notepad):
 12VCT Secondary Transformer
o-----. ,--------o12VAC
 )|(
Primary )|(
 ) ,--------o 6VAC
120VAC )|(
 )|(
o-----' '--------o 0VAC

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

Can't get there (24VAC) from here (12VAC). Whether you use the center
tap or not, you've only got 12VAC. Sorry.

Good luck
Chris

R

#### Roger Johansson

Jan 1, 1970
0
Chris said:
12*2=24Watt

24*2=48Watt

You cannot use a 24 Watt transformer in place of a 48 Watt transformer,
unless you know it will not have to deliver more than 24 Watt.
Nope. The center tap provides a voltage tap halfway between the two
legs, like this (view in fixed font or Notepad):
12VCT Secondary Transformer
 o-----. ,--------o12VAC
)|(
Primary )|(
) ,--------o 6VAC
 120VAC )|(
)|(
 o-----' '--------o 0VAC

created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

Can't get there (24VAC) from here (12VAC). Whether you use the center
tap or not, you've only got 12VAC. Sorry.

Good luck
Chris

Many transformers are made in a way which makes it possible to split
the winding.
Look at the middle contact point in the secondary winding above, the
point marked 6VAC, look at the same point on the realworld transformer.
It is often a sling of copper wire coming out of the winding, and is
soldered to a post.

Desolder it from the post, cut the sling in the middle, connect the two
wires to two separate contacts.

Now you have separated the two 6 Volt windings. The wire is covered
with enamel, so they are isolated from each other even if it may not
look right. Test with a resistance meter that there is no contact
between the two.

P

#### Peter Bennett

Jan 1, 1970
0
Can I use 12V, 2amp centre tapped transformer in place of a 24V/2amp. I
will not use the tapped wire, so I'll get 24volts across its two
ends.

TIA

The "advertised" secondary voltage of a transformer is normally the
full voltage developed across its secondary, ignoring any taps, so you
will only get 12 volts from the 12 volt transformer.

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