[Julius793]

I must have installed the 30a/60a generator transfer switch about a dozen times. Today I was thinking when utility power is restored before you turn off your generator you have two sources of power with all the neutrals connected. How in the world does the neutral current know to go back to the transformer or the generator?

 

[oldtimer]

I must have installed the 30a/60a generator transfer switch about a dozen times. Today I was thinking when utility power is restored before you turn off your generator you have two sources of power with all the neutrals connected. How in the world does the neutral current know to go back to the transformer or the generator?

:001_huh:

 

[8V71]

That's an odd question coming from you. The utility hots are flapping in the breeze so there is no current path in that direction.

 

[dronai]

Electrons are smart little buggers

 

[Julius793]

That's an odd question coming from you. The utility hots are flapping in the breeze so there is no current path in that direction.

Well I guess I left out that the transfer switches are usually only a few circuits so as soon as utility comes back on the rest of the circuits are energized

 

[oldschool]

Well I guess I left out that the transfer switches are usually only a few circuits so as soon as utility comes back on the rest of the circuits are energized

...and those are going back to their source

 

[8V71]

Well I guess I left out that the transfer switches are usually only a few circuits so as soon as utility comes back on the rest of the circuits are energized

Same deal

 

[oldschool]

Well I guess I left out that the transfer switches are usually only a few circuits so as soon as utility comes back on the rest of the circuits are energized

....and the circuits still on the gen are going back to their source

 

[Julius793]

....and the circuits still on the gen are going back to their source

How? Being that all panel neutrals are connected

 

[oldschool]

How? Being that all panel neutrals are connected

I must not understand your question. Why would current (if you have no wiring issues) try to go somewhere other than its source?

 

[8V71]

How? Being that all panel neutrals are connected

You need 2 wires to complete the circuit path. The circuits on the genny are still pulling neutral current from the generator while the utility circuits are pulling neutral current from the transformer.

edit: Forget about the neutrals being connected together. Like oldschool is saying concentrate on the source of the power.

 

[RHWilks]

I theory, there is no potential between the generator and the POCO, so the "noodle" connection shouldn't be a issue. basically it should go from where it came from. Unless, the poco and the generator are running at exact same hz using the same grounding system, and after a good rain or snow. but a 30/60a I wouldn't even spend time worrying about it.. full load 1200 amp I might think about it.
Are you worried about burning up the Genset by noodle load?

 

[8V71]

I think he is trying to get a handle on the basic concept.

Here is a different way of looking at it which may easier to visualize. Take 2 car batteries and set them next to each other and wire the negatives together which would be like your neutral connected to both sources. Place different loads on each batteries positive and negative. Each load will only draw from the battery it’s connected to and the batteries have no idea that its negative is wired to another battery. You could have any number of batteries (or sources) set up like this with all of the negatives wired together and get the same results.