Given a 240 volt circuit:

If we measure the voltage between L1 and L2 we get 240V.

If we measure the voltage between L1 and neutral OR L2 and neutral we get 120 Volts.

Neutral is secured a frame.

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Questions

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GIVEN: We have L1 connected to a Load. The Load then connects to L2.

1) Since L1 and L2 are 180 degrees out of phase, then I assume the Load is seeing 120 volts?

2) Because of the phase difference is L2 just acting like "the neutral" to L1 ?

3) Are the electrons just following back and forth down L1 and L2 OR

are the electrons flowing in both directions such that L2 is the return path for L1 AND

L1 is the return path for L2?

4) If NOT, since the Neutral is connected a frame, how are the electrons getting from L1 OR L2 over to the Neutral?

Thanks

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Answer (included here to highlight for those of us trying to wrap our head around AC ) Please ignore the OP questions as originally stated above, and focus on the following.

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One needs to look at AC as a transformer. For this discussion one needs to ignore the fact that a transformer can be a step up or step down transformer.

The primary is the service connect coming from the power company. The secondary is our supply. The secondary can be equal to the primary -- e.g. 240 volts in (primary) and 240 volts out (secondary). The secondary can also be tapped at various points to obtain any desired voltage. If tapped in the center, each leg would yield 120 volts. Tapping the secondary at some other point may give 24v, 22, 12, or whatever voltage is needed. In a circuit diagram Line1 and Line2 just represents the two legs of the secondary OR the tapped voltage (whatever is that voltage). The circuit diagram will govern as to what is that voltage, or if multiple taps are used, the nomenclature will need to so note.

For a US household with 120 volts, the black wire is one leg of the tap, and the white wire is the other leg of the tap (center assumed). If the circuit diagram shows 240 volts with a third wire going to the chassis, then the 240 volts would represent the end points of the secondary. The third wire going to the chassis is the center tap. HENCE each leg of EITHER secondary wire to that chassis wire will give 120 volts.

Thanks to ALL who responded.

If we measure the voltage between L1 and L2 we get 240V.

If we measure the voltage between L1 and neutral OR L2 and neutral we get 120 Volts.

Neutral is secured a frame.

======

Questions

======

GIVEN: We have L1 connected to a Load. The Load then connects to L2.

1) Since L1 and L2 are 180 degrees out of phase, then I assume the Load is seeing 120 volts?

2) Because of the phase difference is L2 just acting like "the neutral" to L1 ?

3) Are the electrons just following back and forth down L1 and L2 OR

are the electrons flowing in both directions such that L2 is the return path for L1 AND

L1 is the return path for L2?

4) If NOT, since the Neutral is connected a frame, how are the electrons getting from L1 OR L2 over to the Neutral?

Thanks

=====

Answer (included here to highlight for those of us trying to wrap our head around AC ) Please ignore the OP questions as originally stated above, and focus on the following.

=====

One needs to look at AC as a transformer. For this discussion one needs to ignore the fact that a transformer can be a step up or step down transformer.

The primary is the service connect coming from the power company. The secondary is our supply. The secondary can be equal to the primary -- e.g. 240 volts in (primary) and 240 volts out (secondary). The secondary can also be tapped at various points to obtain any desired voltage. If tapped in the center, each leg would yield 120 volts. Tapping the secondary at some other point may give 24v, 22, 12, or whatever voltage is needed. In a circuit diagram Line1 and Line2 just represents the two legs of the secondary OR the tapped voltage (whatever is that voltage). The circuit diagram will govern as to what is that voltage, or if multiple taps are used, the nomenclature will need to so note.

For a US household with 120 volts, the black wire is one leg of the tap, and the white wire is the other leg of the tap (center assumed). If the circuit diagram shows 240 volts with a third wire going to the chassis, then the 240 volts would represent the end points of the secondary. The third wire going to the chassis is the center tap. HENCE each leg of EITHER secondary wire to that chassis wire will give 120 volts.

Thanks to ALL who responded.

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