# How many turns number?

#### apolo02

Joined Apr 30, 2011
9
How many turn numbers at the primary side of the transformer with a centre taped secondary side producing 14.2-0-14.2v. Input voltage is 220vac.

#### #12

Joined Nov 30, 2010
18,224
There is nowhere near enough information in your question, but (turns out)/(turns in) is approximately how you figure the answer. You will need about 7.74 times as many turns in the primary as there are in the secondary.

#### Kermit2

Joined Feb 5, 2010
4,162
Set your problem up as a RATIO

If your 220 Volt primary has 220 turns
Then your secondary would have 14 or 15 turns.

Not exact but close enough to work with.

If your primary has 50 turns
50 /220 = x/14

#### apolo02

Joined Apr 30, 2011
9
Also can diode add voltage in a centre taped transformer? For example from 10-0-10v to 12-0-12v how can i use it 2 add output voltage?

#### #12

Joined Nov 30, 2010
18,224
You can't. Diodes don't generate voltage.

#### Kermit2

Joined Feb 5, 2010
4,162
Diodes are used to RECTIFY the AC voltage into DC voltage.

#### apolo02

Joined Apr 30, 2011
9
Kermit2,my problem is on what exactly we mean by turns,and how can i measure that this is a single turn.so pliz help me.

#### kubeek

Joined Sep 20, 2005
5,776
For a standard EI transformer, 1 turn is one complete loop around the middle post. The actual number depends on area of the center post, voltage and frequency you want it to use with.

#### wmodavis

Joined Oct 23, 2010
739
True! Diodes don't generate voltage but they can, in conjunction with capacitors, be wired into a voltage doubler circuit. Right?

#### #12

Joined Nov 30, 2010
18,224
@ wmodavis Not the way this guy wants it. Look at post 4. He wants to add 2 RMS volts to each winding. You simply can't teach a diode to do that.

#### apolo02

Joined Apr 30, 2011
9
I simply want to connect a diode on each end side of a centre tap transformer just b'cos my transforme normally generate 6.3v-0-6.3v and i want it 2 generate 7 volts to each side in the secondary side so that to get 14.3v-0-14.3v can diode generate? If not so what can i do to get that amount of voltage?

#### kubeek

Joined Sep 20, 2005
5,776
The transformer generates 2x6.3V AC? And you want to get 2x14.3V DC?
Then a voltage tripler could get you near that. What current can the transformer supply and how much do you need?
Remember you can´t get more power than the transformer is rated for.