What's the hazard here?

…aside from the unprotected splice, what exactly is the danger represented by the shared neutral? It doesn’t seem as likely to overheat as the hot conductors, since it’s returning power to the pole, there’s no draw, right?

Speaking of splices, in order to write the electrical courses for Mexico, I thought I’d pick up a book on Mexican electrical practices. Here’s how they recommend splicing. They just wrap them in vinyl tape

Current(draw) is the same but there is not much push(voltage) left.

The voltage drops across the connected load.

Kirchhoff’s circuit laws

So basically, their splices are similar to our old K&T splices? (Haven’t seen an exposed one in quite a while, so don’t exactly remember).

So it should be commented on as incorrect but not particularly hazardous?

I’m not sure. They look like effective spices. I’m trying to figure out what to say about stuff like this. I guess as long as it’s enclosed in a rated junction box it’s OK as long as it’s stapled. But it won’t be stapled because all the walls here are plaster-covered masonry with wiring run through the block cells. But I guess if it’s inside the cells it can’t be tugged on easily.

Electrical here is SO BAD. No license required to install it, no inspections, one of the most common conditions is this:

Kenton, What am I missing here? I see a 240 feed with a neutral; they split the feed and run 120 volts into each separate weather head. Do they bring the separate feeds back together at the panel to again have a 240 volt service? If so the shared neutral is no problem as it is still the same 240 feed. I don’t like the way the neutral is wrapped around the mast. I would call this out if I came across it for review; by the way I have never seen this set up in all the years I have been inspecting and for that I feel if requires an electrician or the utility to check it.

That just looks like one triplex feed to two 120 volt services. The bare would be not more of an issue than if it were SE cable with a bare neutral.

Jim, Any comment on the splice?

Tequila !
And we will wire anything .
Holay !

I worked down there for about 5 years between Monterey, Chihuahua and Guadalajara.
After that I believe anything is possible.
Montezuma’s revenge got me the first month, bout died !
I was hoping for death !

Jim, I don’t know your background but I do know you post a lot in the electrical section so I assume you have knowledge. The set up that you call a triplex feed I have truly never seen before. Is this something that you would call out for correction. I know I have not seen it all in 14 years so I am always willing to learn something new.

This is two services for two different houses, with one service drop splitting into two masts, each with a 120-volt feed and one neutral splitting off to serve both systems.

This is in Mexico, Mark. No license required here to install electrical. It’s not inspected at the time of construction. And it’s bad. Cuernavaca is a pretty nice city, but there are meters missing all over town with the energized components exposed to touch. Check out the low-hanging wires between poles, which is not common, but it’s here.

To a great extent, they don’t have general contractors here or very many subs. Architects take the place of general contractors and the same guys do everything… foundation, masonry walls, plastering, electrical , roofing, etc.

Missing meters with exposed components are not perceived as dangerous.

I have yet to see a weatherproof junction box. They all look like the one in the picture below.

This is just for the Exterior course, which includes the service equipment. I don’t know what’s going to happen when I do the Electrical course.

Kenton,
Thank you for the explanation…I guess your real problem is where do you start!

…or where to stop! I have a feeling writing that course is going to be like “The Never Ending Story” meets “The Telltale Heart”!

Hell you didnt have to go to mexico dude! You could have come here, I see some of the same stuff.
I would think sharing a neutral for 2 residences would not be the best by far.

Mark, a triplex is simply 3 conductors, typically 2 insulated hots and a bare neutral with a steel messenger strand to support the weight of the cable. You can Google ASCR cable to see an example. Triplex cables feed many portions of the country that still have overhead services.

As far as the bare splice on the neutral that is very common. The whole neutral is bare all the way back to the pole in the triplex.

No, I am not an inspector, but a Master electrician.

If the triplex is sized correctly I am not imagining any issues.

Jim, do you see a danger from splitting the neutral to two separate services?

I am not seeing any issues as long as it is sized properly. It is only going to carry the imbalance between the two hots, just like any other MWBC.

It is common here to see one triplex feed two rowhomes. The point of attachment is between the two on the property line.

As far as the photos of the splices, these are not as bad as one might suspect. Wire wound splices, or “wraps” as some old timers called them, is a highly effective method of splicing when done properly. Many electronic systems use modifications of this method in connections that are subject to vibration, stress, and thermal expansion. The American Electrician’s Handbook still details very similar methods to splicing conductors. However, it is often recommended to complete the connection with solder. My main concern would be ensuring the connections are well insulated once completed.

I assume twist on wire connectors (wire nuts) are not readily available or are cost prohibitive?

I dont think I would try and tackle authoring a comprehensive electrical code, rather focus on assuring the wiring methods that are used are complete, sized properly, insulated, and present no immediate hazard. I have removed a considerable amount of bad wiring in my days, and surprisingly the vast majority of it was still functioning and was not on the brink of catastrophic failure.

I don’t know why they don’t use wire nuts. I saw some at Home Depot here in Cuernavaca. Part of the reason for things being done the way they are is that it’s part of the culture, also, labor here is very cheap. A few blocks form me, they’re building a multi-story apartment building, al CMU. It’s probably 60 units; a good size building. They mix the mortar in a mixer across the street in a vacant lot and guys carry it across the street and up to the masons in buckets carried on their shoulders.

They already have national, state, and local standards, it’s just that they’re ignored and there’s no enforcement. I’m sticking to writing a course on inspecting electrical that concentrates on system and major component defects and safety issues. I can use the US codes for that with a disclaimer that it’s not a course on Standards and inspectors should find out what standards apply in the areas in which they work.

This brings back memories from trade school 1952 .
Western union splice .


We had to these and also seven strand then solder the joint .we then had too cut it open to make sure we did not have a cold joint ( no solder in the centre ) .
A proper joint had cambric tape then friction tape then Glyptol paint .

well explained William …thanks Roy

Are they expensive as compared to the states? I guess the underlying issue is simply a lack of enforcement of existing standards. We often run into this in the south. I was talking to a property manager in Pigeon Forge, TN the other day and they specialize in cabin rental. She was complaining about the numerous issues they encounter with the maintenance of the properties. Apparently, the good ol boy network was in full swing with codes enforcement for many years in that area and many cabins have a considerable number of deficiencies they continually deal with.

Yes, Roy, the good old Western Union splice! I started to mention the name, but I thought most would assume it was only for communication cables. I have used it numerous times to replace conductors in a conduit. It is amazing the strength the connection has when done properly. However, I have never utilized it as a permanent means of connection in a conduit.