Hi

Though I'm posting it here, it's has nothing to do with homework. It self-study. I'm a beginner so please keep your reply simple. Thanks.

Suppose a CTT (center tap transformer) splits the voltage across its two secondaries into 120V each. I want to get combined voltage of both secondaries which would be 240V (120V + 120V).

How do I do this?

I have drawn this diagram, "B" is a bulb:
http://img97.imageshack.us/img97/9539/ctt1.jpg

One things more. Suppose in the primary current is flowing upward at some instant (current keeps changing direction in AC, correct?), in which direction the current (or current) would flow in the secondaries? In the same direction, as is shown in the below diagram, or in the opposite direction.

Currents in the primary and the secondaries:
http://img194.imageshack.us/img194/6163/ctt2.jpg

Many thanks for your help and your time.

Regards
PG

 

I Simply cannot register to view ur image.
Try photo bucket for a change

 

To PG1995:

Your schematic (ctt2.jpg) shows one half of the secondary (the top side) shorted out from 0V to Line 1. That would eventually destroy the transformer or (hopefully) activate whatever primary side over-current protection exists. To obtain the full 120V across the load you would leave the 0V terminal disconnected (open) and connect the load between Line 1 & Line 2.

Your other schematic (ctt1.jpg) also shows a situation where the secondary is short-circuited. Lines 1 and 2 connected as shown are effectively a short. Unless the two secondary windings are completely independent (2+2=4-wire) you can't connect them in parallel. You can't connect the outside ends of a center-tapped (3-wire) winding. The "polarities" are not compatible with this connection.

 

I Simply cannot register to view ur image.
Try photo bucket for a change

Hi R!f

I don't know what's the problem. It's a direct link. You don't need to register to view any of the images if you have a direct link. So, please try to check it out and let me know what the error is. Thank you.

Regards
PG

 

To PG1995:

To obtain the full 120V across the load you would leave the 0V terminal disconnected (open) and connect the load between Line 1 & Line 2.

That should read .....

"To obtain the full 240V across the load you would leave the 0V terminal disconnected (open) and connect the load between Line 1 & Line 2."

 

Funny..I get a domain blocked error

 

Funny..I get a domain blocked error

Perhaps, it has something to do with your ISP, or your avatar!

Regards
PG

 

That should read .....

"To obtain the full 240V across the load you would leave the 0V terminal disconnected (open) and connect the load between Line 1 & Line 2."

Thanks a lot, t_n_k. It has been really helpful. I do have some follow-on question on transformer which I would ask soon. And I understood it was just a 'type'.

Best wishes
PG