Fried geckos mean inventive wiring job

The Joy of Construction in Mexico Part 3 — The Case of the Toasted Geckos

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gecko

Fried versions of the common gecko are an indication that the electrical work might not be up to snuff.

When I started doing home inspections in the 2007/2008 winter season in Mazatlán, I quickly discovered Mexican electrical work to be more inventive than I had expected.

Without any laws governing the electrical trades or codes covering the installation of a residential electrical service, ineptitude can muddle the end result. I soon ascertained that to be an electrician in Mexico, all you need is a pair of pliers and a roll of tape — and the tape is optional.

As I reflect on all the electrical work I have inspected, no single word comes to mind that could possibly describe the entirety of the horrors I have stumbled into over the past few years. To be more linguistically precise, Mexican electrical work can run from aberrant to whimsical, from arbitrary to unstable, as well as desultorily dubious, and on occasion deceitfully devious.

Before I get any further into this, I need to provide my readers with a little basic knowledge of 120-volt residential electrical services (240-volt is beyond the scope of this dissertation).

Electrical current flows through a wire like water flows through a pipe. A 120-volt electrical service distributes power with one wire that has voltage as well as a wire known as a neutral, along with a ground wire. Therefore, all properly wired systems have a hot wire, a neutral and a separate ground wire that is independent of the neutral at the receptacle but conjoined in a common bonding bar at the main panel.

When voltage flows through a light bulb, or any type of electrical device, it is seeking the neutral to complete the circuit. The light bulb, or electrical device, which is in between the voltage and the neutral, utilizes most of the voltage to operate, but a few stray volts will continue through the bulb or device and flow to the neutral wire, which is safely grounded — or should be.

Since the neutral is normally grounded, many Mexican electricians don’t bother with a separate ground wire because they believe the neutral will suffice. Because of this erroneous assumption, many Mexican electrical services are only a two-wire system, without a separate ground wire.

If the neutral side of the service has been properly grounded, a two-wire system will work just fine without a separate ground wire. However, if the neutral is not grounded things can get dicey.

The electrical meter is where the utility feeds power to the home and where the utility neutral should be wired to a copper rod, which is driven into the ground. If, for some silly reason, the electrician fails to drive the ground rod and bond it to the utility neutral, those stray volts left over from all the bulbs or devices just collect in the household neutral wires looking for any convenient ground.

One day I received a call from a woman who explained that she was getting shocked by all her appliances and lamps. She had just moved into her new house in an upscale-gated community, and the architect who had designed and built the new home kept telling her she was imagining the shocks.

Of course, the architect refused to check it out personally or send someone to assess the problem, because she was just another hysterical woman complaining about nothing. It was after several weeks of frustration that she called me for an electrical inspection.

Upon arriving, I asked her to show me something that was shocking her, and she pointed me to the refrigerator. I reached out, touched the side of the gently humming appliance and got a good strong zap. I took my electrical tester and placed one lead on the fridge and the other on the copper line for the ice-maker.

I removed the cover on an outlet box and then carefully removed the live receptacle and found the first couple of mummified geckos at the back of the box. The receptacle looked to be wired properly with one hot wire, one neutral and a bare copper ground wire. Sure enough, when I lightly touched the bare copper ground wire I got the same zap as at the fridge.

I then pulled the cover on the main electrical panel and checked the wires, breakers, the neutral bonding bar and the grounding lug. The grounding lug did not have a wire, and there was no sign of any copper rod in the surrounding ground; there were, however, more than 10 shriveled gecko carcasses.

I next went to the meter base, carefully removed the anti-tamper seal and pulled the meter. Once again, the grounding lug was without a wire, but no dead lizards this time.

Without a grounded neutral, either at the main service or the meter base, and since the neutral bonding bar in the main panel also accommodates the bare copper ground wires to the outlets, those stray volts carried by the neutrals electrified all her metal encased devices and appliances which had a three-prong plug.

Out of curiosity, I removed several covers from electrical boxes in different rooms and all but one contained fried geckos. I think when the house was built all the electrical boxes and conduits were in place, but the switches, plugs, and cover plates were not immediately installed.

This allowed sufficient time for the tiny green invaders to make themselves at home in the conduits and boxes. Then when the house was completed and the power switched on, I am sure the snap, crackle and pop of sizzling lizards, encountering the electrified ground wires, was markedly audible.

This column is the third of a series by Bodie Kellogg, who describes himself as a very middle-aged man who lives full-time in Mazatlán with a captured tourist woman and the ghost of a half wild dog. He can be reached at buscardero@yahoo.com.

Source  : Mexico News Daily

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