I need help understanding AC electricity and generators (1/3 phase)
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CalG
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I wonder how it (phase angle) might be explained as one would explaine the difference between batteries in series (voltage add) vs batteries in parallel (current add)
Obviously, "current add" is meaningless when there is relatively infinite current available "on the tree" for domestic applications.
But think:
If someone (not me ;-) hooked up a panel load to ALL the breakers on the right side of the panel, they would , in image space, be adding current to a 120 volt circuit ALL IN PHASE.
Same goes for a similar hook up ALL on the left side breaker terminals. It's still just 120V
But add connection to even a single breaker from the opposite side via a lifted and replaced neutral, and there is 240 V available to blow out all the light bulbs ;-) or drive the well pump and clothes dryer.
Is that other side "in phase" or "180 out of phase" ? Might be semantics.....
Bottom line, by my own experience, any two legs of a delta 3 phase system will run a 240 volt motor. or heat a water heater element ;-)
Obviously, "current add" is meaningless when there is relatively infinite current available "on the tree" for domestic applications.
But think:
If someone (not me ;-) hooked up a panel load to ALL the breakers on the right side of the panel, they would , in image space, be adding current to a 120 volt circuit ALL IN PHASE.
Same goes for a similar hook up ALL on the left side breaker terminals. It's still just 120V
But add connection to even a single breaker from the opposite side via a lifted and replaced neutral, and there is 240 V available to blow out all the light bulbs ;-) or drive the well pump and clothes dryer.
Is that other side "in phase" or "180 out of phase" ? Might be semantics.....
Bottom line, by my own experience, any two legs of a delta 3 phase system will run a 240 volt motor. or heat a water heater element ;-)
strantor
Platinum Member
Well as I said transformers don't break the laws of physics. For some reason when we talk about transformers, all the sudden it's ok to insist that waves adding up to double amplitude are polar opposites of each other. But deciding the words we to use to describe its outputs is the extent of the transformer's magic. It is bound by the cosmos to keep outputting two waves in phase with each other, no matter what we say or where we connect our ground clips (that is, until one of us blows a fuse).
CalG
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Isn't it curious that a 115 volt circuit has one side to ground/ neutral. and a 200 V circuit needs no ground or neutral to do useful work.
MAGIC! Fun with generators.
In an emergency, the house can FLOAT! ;-) Well, at least the electrical part can. This may not be the best expression considering the expected weather for the gulf regions.
MAGIC! Fun with generators.
In an emergency, the house can FLOAT! ;-) Well, at least the electrical part can. This may not be the best expression considering the expected weather for the gulf regions.
strantor
Platinum Member
I can't believe that the answer with the most upvotes was a toddler's crayon drawing, yet again someone with no concept of RMS voltage showing peaks and valleys of +/- 120V. There were so many better answers. This one was my favorite.
Unfortunately I was unable to upvote it as easily as I was able to fix Wikipedia ( you must have an account to upvote).
The interaction of water and sound waves in the same plane is not the same as a direct comparison to the output of a center tap transformer. You can generate electric sine waves on same wire (plane) and the waves will interact but this is not what's happening here. It's sine waves being generated on the separate sides of the center tap on the secondary coil of a transformer.
You are correct about one thing. Connect L1 and L2 directly together they will definitely cancel each other out. It's a good thing they are connected through a load.
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3Ts
Elite Member
I understand the points y'all are trying to make. However, for most the folks on this forum the reference point needs to be the neutral in a center tap transformer since that is what 99% of the folks will be dealing with. Those who get into multiple phase power sources really need to do their homework before connecting to their house - and understand both points being made in this discussion.
strantor
Platinum Member
Did you watch my video? I connected two (separate) transformer secondaries in the same configuration as a single split phase secondary, out of phase with each other and result was (N-L1: 120V, N-L2: 120V, L1-L2: 0V). I then connected them in phase, and L1-L2 went to 240V.
They are related. On a house split phase L1 and L2 120v are 180 degrees opposite and 240v difference. Substitute 2 of 3 phases of 120v generator that's 120 degrees apart the the voltage differential between L1 and L2 goes to 208 because the waves are shifted.
Since every text book in the world has a split phase transformer defined wrong you need to publish your own.
