Don't turn this around on me, you were the one calling things nonsense. i
don't have to take that. you are being arrogant. somehow in your mind
because i ask for knowledge, you seem to think i am beneath you
reqluq firstname.lastname@example.org wrote previously in
As you are ASKING, certainly you are beneath me (as you want to put it) in
this small, specific topic. If I call things nonsense is because I know
better about that. Be more receptive and you will learn. I still believe
that is possible for you.
But this is not important, what matters is that once answers has been
kindly, with good intentions, given to you, you thwarted them, without
exerting some analysis and thinking.
Instead of thinking and describing what you understood of what was given,
you asked unrelated questions, as if all the knowledge you need could be
condensed in one very simple "layman" phrase.
You need to learn a lot of things, learn to use the language of the trade,
and listen to what others explain to you.
If you want help, be humble, not arrogant.
Only if the two generators were synchronized in frequency and
in antiphase. Highly unlikely unless specific provisions are
made to assure the synchronization is constantly applied and
the conductors are properly attached. Based on your questions
I would not recommend you try this at home before you take
that electronics class.
So you are saying that there is some form of synchronisation going on at the
plant to let one wire be used opposite to the other at a time? Then back to
the question of; can you hook up some kind of relay switch with one 110v
wire and send 110 to one side of the 220v appliance and then switch over and
send 110 to the other leg hence 220v?
Just to be clear what I am saying: you say that when one line of the 220
system is sending 110 to the appliance the other is acting as neutral. Then
the one that was neutral sends 110v and the other is now the neutral? So I
can in essence send 220v using one wire: I have a switch or solenoid
whatever that the 110 wire is hooked up to; It has two wires from it one to
one side of the appliance and the other to the other side.a neutral (for
these purposes) is factored in. So current comes on one side of the
appliance then the switch switches over to the other side and send a 110v
there back and forth and so on. Hence 220v no?
No, you can not send current to an appliance over one wire! You are getting
the answers, but you are not equipped with the knowledge to understand them.
You need a better knowledge of basic electricity, what a circuit is, etc.
You can't get it with a few responses on a newsgroup. As was suggested, you
either need to take a course or else study a good textbook on the subject.
Benjamin D Miller, PE
NO! The synchronization is happening in the transformer on the
power poll out in front of your house.
Then back to
NO! If you load is ballanced there is no current flow in the
neutral and it can be ignored. Neither of the hots ever acts
as the neutral.
NO! You have both hots going max positive and max negative at
one time (220) then going max negative and max positive at one
time (220) Alterntely switching in phase 110 will never put
220 across the load at any given time, it will just remove
power from each leg half of the time.
Your house is supplied from a single 220 V transformer which is
center-tapped, and the "neutral" wire is connected to that centre tap.
A device that needs 220 V is connected to the two "hot" wires and sees
220 V. But you can also connect 110 V devices between either "hot" wire
and the "neutral", since only half the transformer winding will supply
the power, and it thus gets half the voltage.
Half of your 110 V devices will be connected to one side of the
transformer, and the other half to the other side, more or less.
At any given moment, some of your 110 V devices are receiving voltage of
the opposite polarity from the other devices, but that doesn't bother
Similarly, if you have a *single* 220 V generator with a centre tap, you
can connect both 220 V loads and 110 V loads.
But, unless you have special synchronization controls on the two
generators, you can't connect two 110 V generators to make 220 V,
because two generators will not stay exactly 180 degrees apart in phase
at the same frequency.
If you have one 220V generator that isn't big enough for your load, you
can connect another 220 V generator *in parallel* with it such that both
share the load. But it requires special equipment to bring the two
generators in sync before they are connected (if not, you'll destroy one
or both of them), and to share the load evenly.
Yes I know; I put my tester on the two hots and it shows 220v. How it does
is the mystery
But you can also connect 110 V devices between either "hot" wire
Thank you Thank you Dave. I always thought when I see 2 or three
transformers that was 2 or 3 110 volt cables. I didn't realise the
transformer itself was 220 and two wires of 110v would come off it.
It's slowly getting a bit clearer.
Great that's kinda of what I gathered reading in here so far.
So what keeps the two 110s from the transformer exactly 180 degrees
apart assuming the power to the transformer is from one source?
It can be done in theory (using both lines from each generator and
connecting the + of one to the -of the other just as with batteries) that
way but I wouldn't recommend it. Practical problems do arise with AC as it
would be necessary to synchronise the machines (bring them to exactly the
same frequency, voltage magnitude and phase). This is routine for
generators on the grid but they are not in series. While it has been done
for DC , it is a hassle- particularly for the inexperienced, and as far as I
know it hasn't been done for AC although it has been done for DC about 100
years ago (Thury DC link).
It is simply not worth the effort to do it. It is much easier to use a
single generator with a center tap (neutral) on the winding than to use two
machines- and this is what is done for 120/240V machines.
For a transformer the primary is single phase -say 2400V and the secondary
is then a 240V winding which is center tapped so that one can get 120V from
either end to the neutral.
This 3 wire system was originally set up by Edison for DC systems and later
adapted to AC use.
Don Kelly email@example.com
remove the X to answer
It's 120V, but there are two of them to make 240V (between them).
Yes, you're over-figuring. ;-)
Here is where your misconception is. True, each "leg" goes from
positive to negative (with respect to neutral), but at different
times. When one leg is positive the other is negative. The
*difference* between them is 240V.
Sure, I see what you're where your misconception is but it's buried
deep in your mind. ;-) The other line is not being used "as a
negative". Both are positive and both are negative (hence
"alternating" current), but at opposite times. The *difference*
(voltage is always a difference - there is no absolute) between one
leg and neutral is 120V. The difference between the other leg and
neutral is 120V. The difference between the two is 240V, since when
one is positive other is equally negative, at any given time.
1/120th second later they're at opposite polarities.
Say you are on top of a building 110 metres high, and there is a 110
meter hole in the ground below.
The building height is +110m relative to ground ...
The hole dept is -110m relative to ground.
Now jump. What distance would you travel to the bottom of the hole?
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