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Hi so I’m an electrical engineer visiting some family in Ecuador and after some wiring has stopped working In the kitchen I have decided to rip out the 40 plus year old installation and reinstall. This is a bamboo farm house fed with a 2 wire overhead installation to a smart meter and then two 60 amp breakers, one is for the neutral. Both are accessible for a safe disconnect at least. That’s what the utility has provided. The meter is grounded with the ACSR cable from the overhead I assume it’s providing ground. Now the interesting part. After the meter and the two breakers the house is serviced with two tiny #12 gauge wires to a single 50amp breaker and then a whole collection of junction boxes to feed everything in the house. There is no ground wire what so ever after the meter and the third prong on the outlets have just been filled with cement. That is the way here from what I’ve observed. No grounding or bonding and the ground prong removed from appliances that require them.

With that said I will service with larger cable and provide a panel with a neutral and ground bar and run all three wires through the installation. My question is could there be something I’m overlooking grounding this one house while the other houses that are fed from the pole mounted transformer are left ungrounded and with a floating neutral? If the neutral has some electric potential to it on the line, could it be dangerous to connect the neutral in the panel to the ground bar and then to the main water pipe? Any thoughts appreciated thanks!

  • Is the utility transformer's secondary grounded? – ThreePhaseEel Feb 16 at 7:06
  • Not sure would have to walk out to the pole. I’ll be able to check in a few hours. – Andre Pin Feb 16 at 12:30
  • Are the 12AWG wires run overhead in free air, or are they in a cable or conduit? – ThreePhaseEel Feb 16 at 17:29
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    They were dangling from the first floor to the second after the meter. Since then they have been replaced and are in conduit now. From what i can see the transformer isnt grounded and is a single phase 120-n-120 37.5kva can – Andre Pin Feb 16 at 20:22
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Ecuador is kind of on the fuzzy edge of 120V/NEC territory, so you might have Euro 230V in places.

The ACSR service drop is providing netural, not ground. If the neutral wire breaks, it's perfectly normal for neutral to float up at hot voltage. That's why we insulate it. The problem with bootlegging ground off neutral is now, all the grounds in the house are also energized.

So you should fit a normal at-the-house Grounding Electrode System, to whichever level of detail you wish to replicate NEC standard practices. I don't think your AHJ is going to stand on two ground rods and AFCI/GFCI for everything.

Although, given the local fetish for removing ground pins, circuit-level GFCI protection is a VERY good idea. While it does nothing to protect equipment from ESD, GFCIs do everything to protect humans from shock, and serves that purpose better than grounding actually. However it is vital that ground not be bootlegged after a GFCI; doing so utterly defeats GFCI protection.

As long as the #12 is on an outdoor pole line, I couldn't care less. That's typical of the downsizing you see on service drops - many a 100A service has #6 aluminums, a comparable downsize. If it's inside walls in any way, then yes, that's unacceptable and it's time for appropriate sized wire.

Seriously the money spent upsizing the service drop should be spent on GFCIs instead. I trust you know how to use LOAD to protect an entire branch circuit from one device, though, don't protect too much or the cumulative tiny leakage from many devices will cause a nuisance trip.

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  • I have my meter with me so I know it’s a 120v service what confuses me aswell is there is a white, black and the ascr cable. In the meter the white is fed to L1 the black to L2 and the ASCR to N. but only the white and black feed the house the ASCR is cut dead after the meter. The potential between white and black is 120v. I agree with your above comments however. – Andre Pin Feb 16 at 22:26

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