[mjw987]

I have a 220v line run from my house to an outside spot. The line was originally used for a lake pump which has been removed. I would like to extend that power line to 2 new outside outlets. Both outlets may be used for either 110v or 220v devices. Can I use the already existing 220v line or is it necessary to have both a 110v and a 220 v line? Thanks.

[Stratmando]

You will need separate lines, they can't share anything except for ground.

[GermanDAWG]

It depends on the number of conductors (wires) you have. If there are only 2 0r 3 wires then you have a 220 Volt circuit with a ground (in the case of three wires) and without a ground if you only have 2 wires (not common). If you have 4 wires then you most likely have a 120/240 volt circuit because the 4th wire is most likely a nuetral (not a ground wire).

If you have 3 wires it may be possible to use the third wire as a nuetral and drive a ground rod at the site where you have the outlets. You would then need to connect a grounding electrode conductor to the ground rod. It would be best if you placed a subapnel at the sight and used breakers to protect the outlets, wiring and devices from over current. Your homes service is nothing more than a 240 volt circuit that has a nuetral wire so that you can attach 120 volt devices to it.

[benaround]

It depends on the number of conductors (wires) you have. If there are only 2 0r 3 wires then you have a 220 Volt circuit with a ground (in the case of three wires) and without a ground if you only have 2 wires (not common). If you have 4 wires then you most likely have a 120/240 volt circuit because the 4th wire is most likely a nuetral (not a ground wire).

If you have 3 wires it may be possible to use the third wire as a nuetral and drive a ground rod at the site where you have the outlets. You would then need to connect a grounding electrode conductor to the ground rod. It would be best if you placed a subapnel at the sight and used breakers to protect the outlets, wiring and devices from over current. Your homes service is nothing more than a 240 volt circuit that has a nuetral wire so that you can attach 120 volt devices to it.

GermanDawg, Never,ever, tell someone to drive a ground rod and use it for the equipment

Grounding conductor of a circuit. If the (hot) conductor of the circuit faults to a ground rod,

The circuit breaker will never trip, leaving all the metal parts energized and ready to kill

Someone. A GROUND ROD WILL NOT CLEAR A FAULT.

[Tev]

If the (hot) conductor of the circuit faults to a ground rod,

the circuit breaker will never trip, leaving all the metal parts energized and ready to kill

someone. A GROUND ROD WILL NOT CLEAR A FAULT.

Sorry about this slight derailment of the thread but for my own info please explain this.
I would think that a low resistance path to earth would result in an increase of current flow which in turn would trip the breaker. If I'm missing something please point it out.

[benaround]

Sorry about this slight derailment of the thread but for my own info please explain this.
I would think that a low resistance path to earth would result in an increase of current flow which in turn would trip the breaker. If I'm missing something please point it out.

Tev,

A lot of people wrongfully believe the same thing. Electrons leaving a power supply are

Always trying to return to the same power supply, they are not trying to get into the earth.

The equipment grounding conductor ( EGC ) in a circuit bonds all the metal parts, i.e..

Boxes, pipe, enclosures, etc. to a low impedance path back to the Grounded Conductor

( neutral ) this path ensures that the fault will be quickly cleared by the circuit protection

Device. ( circuit breaker )

An example: a 120vac fault to the earth of 25 ohms will only draw 4.8 amps, not enough

To trip a 15a breaker. Tev, I hope this helps- if not tell me , OK

[Washington1]

Yeah... having a low impedance fault current path from metal parts to the power source will ensure a line to case fault will be cleared. The earth is not a low impedance fault current path. See 250.4(A)5

[Washington1]

In other words, I agree with benaround--I think ;) Joke!

[Tev]

Electrons leaving a power supply are

always trying to return to the same power supply

Doh, that's the part I was not putting together. I knew that but for some reason it didn't click that the more earth between the fault and the grounding electrode the higher the resistance thus making the earth an ineffective fault current path.

The earth is not a low impedance fault current path. See 250.4(A)5

And thank you for making that connection in my brain easier.

I appreciate the lesson gentlemen. :)