panel education

walkergetx

I've been looking into adding a generator and started studying my breaker panel. This is a 20 year old Westinghouse. One side is a combination of joint amp breakers. example: Two 20/50 breakers
Disposal 20
AC 50 (joined to the other 50)
AC 50 (joined to the other 50)
Dishwasher 20

Why do this instead of two 20s and a single 50? In addition to this, I have 2 sets of 20/40s like this and 2 sets of 20/30s.

Also, in addition to the main, I have two joined 50s labeled "Main Sub" ?? This doesn't seem to make sense either. I do have an additional breaker panel for the pool equipment. Would it be fed from that?

ME not EE, so I admit to being dum at this. Any help is appreciated.

a7ecorsair

240 Volt appliances require a two pole breaker. Your AC is a 240 Volt 50 amps circuit.
There is a sub panel for the pool. It has a 240 volt 50 amp feeder.

walkergetx

Why not use one double pole breaker instead of crossing over two 20/50s? Cost?

This
http://www.google.com/products/catal...d=0CIEBEPICMAM#
Instead of this
http://www.google.com/products/catal...ed=0CGgQ8wIwBA#

a7ecorsair

The second picture is a quad breaker, two - 240 volt circuits utilizing the same panel space as a two pole breaker.

walkergetx

"I see", said the blind man. More circuits in the same space. Thanks. Now to find a spot for the generator connection....