private electrical system in the jungle of Costa Rica

[sassyandkim]

Hi guys. 1st time posting. In 2005 I installed a private system connected to the local electoral company. I did this because they would not give me power at the house. Too far from the road.
The system consists of a 35K booster to 4200 V and 2 10K bucks. Every this works great, although running the transformers is a little pricey.
Here is the thing. The other day I went to the meter box to replace the main shutoff. Lots of oxidation in the jungle near the beach. While I was replacing the switch I looked up and saw that the neutral on the 4200v side of the booster was no longer connected to the transformer. The thing is, THE SYSTEM IS STILL WORKING AT 100%. I have no idea when I lost the neutral.
So to all of you who are interested in helping me out, my question is why?:?
On a side note, it seems as though my electric bill has been less the last few months.
grateful for any help you can give me. I'd like to understanding this issue
thanks Kim

 

[ATSman]

Not enough info

Not enough info

Send us a sketch of the complete system. Need to see what is downstream of the 4200v winding. Maybe that neutral is not needed and was never connected.

 

[kwired]

Hi guys. 1st time posting. In 2005 I installed a private system connected to the local electoral company. I did this because they would not give me power at the house. Too far from the road.
The system consists of a 35K booster to 4200 V and 2 10K bucks. Every this works great, although running the transformers is a little pricey.
Here is the thing. The other day I went to the meter box to replace the main shutoff. Lots of oxidation in the jungle near the beach. While I was replacing the switch I looked up and saw that the neutral on the 4200v side of the booster was no longer connected to the transformer. The thing is, THE SYSTEM IS STILL WORKING AT 100%. I have no idea when I lost the neutral.
So to all of you who are interested in helping me out, my question is why?:?
On a side note, it seems as though my electric bill has been less the last few months.
grateful for any help you can give me. I'd like to understanding this issue
thanks Kim

Info a little hard to understand as well. What I get out of it is you have a customer owned transformer that steps voltage up to 4200 volts, (this apparently is a 35 kVA unit?). And at some distance away you step back down to whatever your utilization voltage is at the house (apparently through two different 10kVA transformers?)

If that is correct and when you say neutral (that is no longer connected) you mean "grounded conductor" whether it is a neutral or not, you very possibly have an unintended SWER (single wire earth return) system and that is why it still works. 4200 is high enough voltage you could get by with earth as the return conductor and it would work pretty well. You must have grounding electrodes still connected to the transformers at each end or it won't work at all. If you were under 600 volts - earth doesn't work out so well as the current path for this.

 

[ramsy]

..you very possibly have an unintended SWER (single wire earth return) system and that is why it still works.

Roger that, Mike Holt discourages SWER in practice, but medium voltage distribution, and high-voltage transmission is a different matter, where so designed under engineering supervision.

The Los Angeles Department of Water and Power has been using Single Wire Earth Return for its 5800V distribution for several years now, but that was engineered to use the ocean as a return transmitting medium, after running the insulated cable 5-miles out to sea, beyond public beaches.

If an unintended SWER system exists, then unintended electrocution along the unknown return may also exist. Power company may have refused to alow, or permit this remote installation for good reason. Especially if engineering was not done for proper return path of a SWER system.

 

[kwired]

Roger that, Mike Holt discourages SWER in practice, but medium voltage distribution, and high-voltage transmission is a different matter, where so designed under engineering supervision.

The Los Angeles Department of Water and Power has been using Single Wire Earth Return for its 5800V distribution for several years now, but that was engineered to use the ocean as a return transmitting medium, after running the insulated cable 5-miles out to sea, beyond public beaches.

If an unintended SWER system exists, then unintended electrocution along the unknown return may also exist. Power company may have refused to alow, or permit this remote installation for good reason. Especially if engineering was not done for proper return path of a SWER system.

If I understand the setup correctly, the utility is supplying them, probably with less then 1000 volts, but will not run the long distance from wherever the supply is now to the house location, so that is why they have their own 4200 volt system to span that distance. The unintentional SWER that exists is on the owners own 4200 system between the utility and the house. It is unintentional because a connection came apart for some reason, but the grounding electrodes at each end is still intact and that is why the unintentional SWER condition exists.

 

[GoldDigger]

If I understand the setup correctly, the utility is supplying them, probably with less then 1000 volts, but will not run the long distance from wherever the supply is now to the house location, so that is why they have their own 4200 volt system to span that distance. The unintentional SWER that exists is on the owners own 4200 system between the utility and the house. It is unintentional because a connection came apart for some reason, but the grounding electrodes at each end is still intact and that is why the unintentional SWER condition exists.

Or the long connection may be using center tapped windings on both ends, in which case there is no need to connect the center tap except posssibly to create a ground reference.

 

[kwired]

Or the long connection may be using center tapped windings on both ends, in which case there is no need to connect the center tap except posssibly to create a ground reference.

You are saying that the "neutral" is doing nothing but equipment grounding in that scenario it is not a normal current carrying conductor.

I can buy that, unless all the OP has is a single coaxial type cable run from the source end to the house end, which seems like a pretty good possibility.