Monday, January 21, 2008

FAULTY ELECTRICAL WIRINGS - PART 2

GOING BACK TO BASICS


FAULTY ELECTRICAL WIRINGS - A CLOSER LOOK
(Second Part of a Series of Six)

By Doods A. Amora, PEE 1821
(January 2008)



3.0: JUST HOW SINFUL IS ‘FAULTY WIRING’?

Let us first examine the meaning of the word, 'faulty'.

According to the web’s Wiktionary, the word faulty means: “having or displaying non-perfection”; “there’s something not adequate or not acceptable”. The World Book Dictionary likewise says that, 'faulty' means “flawed”, “not in order”, or “there is a defect”.

But a flawed structure although faulty doesn’t always mean that it won’t work for some reason or purpose. Or a defect in the structure doesn’t always mean that it is not ‘habitable’ - at least momentarily.

Just like the makeshift shanties in the squatter areas, are they structurally sound? Apparently not, and they are structurally faulty indeed! But people are living in there and the shanties served their purpose for long years.

But when tremors and earthquakes come, they unmask the real integrity of the structure.

And remember that eight-storey condominium building caught on TV footage while collapsing by itself, even if there were no tremors? Note that the building was only five years old. The question is: Does it mean that because the structure didn’t crumple when occupied five years ago, the structure is not faulty?

To get my points through, here are some scenarios:

Scenario 1: Given a technician on a workbench wiring several circuits aimed at simulating an automated lighting control system for an edifice. Of course, a number of thin wires are crawling like snakes on his workbench. The simulation, by the way, is to confirm that the circuits he designed for the purpose would work.

Now note: if the circuits worked out as intended, then… fine, it should be sort of correct wiring! If it doesn’t work, then the circuits must be wrongly wired, in other terms, “miswired”. Now, if the technician finally got the correct circuits and got the system to work as intended; would the wirings be faulty? No! But maybe, yes!

Please appreciate that the workbench trial of a messy piece of work could not be described as ‘faulty’ because the technician is always there, tending it, and present all the time. More importantly, the wirings would soon be dismantled after the simulation.

But if the same snake-farm-type wirings are put in place as permanent installation - energized all the time, hidden beneath ceilings or walls in the house or building, then the work becomes faulty!

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(Look closely at the burned conductors that ignited the fire in the adjacent wooden structure. Look also how the wires are installed. Are they not faulty wirings? Where are the conduits? If the wires were overloaded, why no circuit breaker ever tripped?)

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Please note that there’s a world of difference between temporary wirings and permanent installations. Temporary wirings are supposed to be dismantled after an objective is achieved. Permanent wirings are destined to be unattended and 'forgotten' after having been installed – meaning, no engineer or technician manning them all the way through eons of time.

So then, it is a different story when permanent installations are set up, because it must conform to the provisions of the Electrical Code. That’s why the Code is there.

Now, if the installations are violations of Code Rules, are they not ‘faulty’? Note gentlemen that the phrases, “non-perfect”, “not adequate”, “not acceptable”, “flawed”, “not in order”, or “there is a defect” are all referring to the provisions of the Electrical Code.

Thus, an installation may be acceptable to the owner but may not be acceptable in so far as the Code is concerned!

But temporaries in man’s habit tend to go permanent! And the Electrical Code and the authorized practitioners are supposed to spearhead the safeguarding of these eventualities. In the USA, a large percentage of household fires and electrocution are caused by injured cords hidden beneath rugs and carpets. And the extension cords by the way, are supposed to be temporary.

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(Can you allow these snake-farm type installations in your own house or building? If so, the house becomes a snake pit and beneath those nice-looking walls and ceilings are mute witnesses of horrible installations! )

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But why the Code seems economically–unfriendly? People say that following the Code Provisions will cost a fortune! Really…? Isn’t it that minimum standards must still stand-out even after any “value engineering” is applied..? What then is the standard?

Scenario 2: Putting it in a different light, can you allow your electrician to just throw electrical wires like spaghetti beneath your house’s ceiling without the benefit of conduits or any of those “approved wiring methods” by the Electrical Code? “But conduits are expensive, Sir. It can’t be seen anyway, and the lights & outlets are working perfectly”.

If so, the house becomes a snake pit and beneath those painted walls and nice-looking ceilings are mute witnesses of horrible installations!

On the other hand, the house or building owner arguably in his right mind won’t allow it! Why? Because “there is a defect” in it, even if it is supposed to be working!

Scenario 3: Can you allow a # 12 THW circuit protected by a 30-ampere breaker in your own house? The installation happened to be ‘neat & workmanlike’ and it did not explode when energized. And, “should there be a short circuit; the 30-amp breaker will surely trip the circuit”. Fine ...

But if one knows about electrical principles, certainly he won’t allow it, even if it did not blow up during its first energization. Why? Isn’t it a clear flawed electrical wiring? Well then, but why faulty when it did not explode when energized? (Remember the usual argument?)

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(First frame: “There’s nothing wrong with it, after the double walling is completed, the panelboard will become flush mounted”. Where are the conduits? “Conduits are not needed because the wires will not be seen, anyway. And the final double walls will make it clean & beautiful to look at.” DO YOU AGREE?)

(Second Frame: This is a 200 A 3PST mains in a commercial building. Note that all sub-feeder circuits are home ran to the main switch. “It’s working for years, so it must be correct!” Really? Can you identify the dangers & the Code violations in this installation? Is it correct to tap small wires into a large fuse? What if the smaller wired circuits got overloaded or had developed short-circuit?)




(Third & Fourth Frames: Please look closely at the pictures. Can you allow these installations in your own house or building? Aren’t they faulty electrical wirings?)

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There you are my friends, after years of accident-less living, loads had multiplied and the circuit conductors may have been overloaded. No breaker trips because the load has not yet reached the tripping threshold of the over-sized circuit breaker. Meanwhile the smaller-capacity conductors may have melted and burned without our knowing. Alas, when we realized the situation, the house had already been on fire!

Can this happen to a new building that has just been energized? No, because the loads in a new house or building will only reach the brink of its capacity in a distant future. Most likely this scenario can happen when the house becomes old and the wirings heavily loaded by then. Note that an “overloaded circuit” is different from a “shorted circuit”.

Let me elaborate…

Going back to its ‘history’, at first the ‘new house’ described above hosted a small family. Later on, the family grew with increasing number of children. As the number of occupants grew, the load swells, too - that’s a fact. As the head of the family got promotions thus becoming more & more affluent, loads increased because more appliances were brought in for family use. Twenty years thereafter, the children then became grown-ups and got married. Extensions and expansions were made on the original house. Then the additional families acquired new sets of appliances, too. All the while, there was no problem because no circuit breaker had ever tripped off, until the fiery realization.

This is also very true to office and commercial buildings. As clients come and go, depending on the clients' business; assorted equipment, appliances, computers, electronic office devices & gadgets, even small welding machines - usually are brought in the leased space. As long as there are convenience outlets, presto, no problem! Who cares about the branch circuits or the feeders?

The example above aims to portray that the effect of the faulty mismatch of the wire with its over-current protective device does not manifest while the house is still young and while the loads are still low. Now, is the flawed mismatch of the OCPD (overcurrent protective device) viz-a-viz the circuit conductor not faulty?

To this author, it’s worthwhile to mention that violations & non-conformances to any country’s Electrical Code whether in design or installation are faulty electrical wirings.

In the USA (just like in the Philippines), most causes of electrically-started fires are faulty wirings done by “do-it-yourselfers”. Why? Because the “do-it-yourselfers” do not even know that an Electrical Code exists!

(To be continued…)

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