double secondary transformer

It allows 2 isolated outputs from the secondary.

Ed

The more secondaries you have, the more output voltages you get. Many circuits are a lot easier to built if you have multiple voltages kicking around... historically you'd often see something like +5V for digital logic and then +15V and -15V for analog circuitry. Even *more* historically it was something like +6.3V for tube filaments and -200V??? for cathodes and I-don't-know-what-else...

If you burn one secondary out, you have a 2nd chance with the other. :P

D from BC British Columbia Canada.

But seriously..

I've used dual secondary transformers for:

1) Split supplies 2) Isolated supplies Ex: One for power. The other for floating measurement. 3) Secondary parallel or series combo for more current or more voltage option. (Matched secondaries.) 4) To make separate supplies for digital and analog.

D from BC British Columbia Canada.

** AC supply transformers are commonly offered with **dual** secondaries to give the user several options when they use it.

1. Wire the secondaries in parallel and double the current.
2. Wire the secondaries in series and double the voltage.
3. Wire the secondaries in series and use the centre point as zero volts in a split rail (+/-) unregulated supply.
4. Use the secondaries with separate rectifiers, filters and positive voltage regulators and then stack the DC outputs in series for a split rail ( +/-) regulated supply.

........ Phil

1) use Google. 2) you need two (possibly different) voltages. 3) you need some flexibility: center-tapped configuration OR higher current configuration. 4) use Google.

This topic might be too odd to find on Google... It's too trivial and probably makes for dull web page material. Experienced designers know immediately what can be done with dual secondaries. It's not a study item, it's quickly realized thing.

D from BC British Columbia Canada.

Ahhh....a homework problem. Sorry we (all of us) answered.

It's one of those unique homework questions. :)

D from BC British Columbia Canada.

More wire...