Electricity is fascinating stuff.
Whether it is the kind that you can stick a balloon on the ceiling with or the kind that can split a 150 foot Douglas Fir tree from top to bottom.
A long time ago, some dudes that were a heck of a lot smarter than me figured out that they could control the stuff and make it do work for us. Few would argue the benefits of no longer going blind while trying to read by flickering candle light. Of course it has allowed us to ignore the natural rhythms of the day and night, and our bodies have likely suffered accordingly–now the city never sleeps.
But back to controlling the stuff.
There are very specific rules related to electricity that must be obeyed to keep it where it belongs. I am going to resist getting all technical here and suffice it to say that when we don’t keep it where it belongs it will still try to do its thing even if that means trying to “light up” the unsuspecting user. For a light bulb to “work” we force current through a resister called the filament in the bulb. Because the electricity has to work hard to get through the filament it heats up and starts to glow. It is the glowing part that we are looking for–because now we can read past bedtime—and warm our hands with it—just like a candle. As long as everything stays nicely contained inside the bulb and the wires all is good.
To cut to the chase, humans do not make very good light bulbs. We either dance around insanely or we just lie there and don’t do anything–ever again.
On a recent inspection I found this electrical panel that was indeed a curiosity.
In most electrical circuits we need to have a hot wire and a neutral wire–of course 240 volt circuits are a little different, but in its own way a neutral is also present. I don’t want to get into all that right now. Of course in modern wiring there will be a ground wire too–but that is not necessary to make the light bulb light up or for you to light up. The neutral wire is there to carry the unbalanced load of the circuit back to ground–or in the case of a circuit that has a ground and a neutral, whatever amount of current the appliance is using would travel on the neutral–and not the ground wire. Whenever we use any electricity a small amount of current will always be running on this neutral wire back to ground in either a 240 volt circuit or a 120 volt circuit. If the current is too great–as in a short circuit–the fuse would blow or the breaker would trip.
So take a look at the panel above.
If you look closely, you can see there are only two wires coming into the box–there is no neutral wire at all. You can see that each wire connects to the main lugs of the panel. This means that any unbalanced load on the circuits is going to be traveling on the metal conduit that surrounds the two wires running into the panel. This of course assumes that the metal conduit is in fact connected to ground back at the service panel. (We can guess that this might be so because the circuits were in fact functional.) Obviously anyone touching that metal conduit is at risk of electrical shock if they themselves are grounded. Under the right (actually wrong) conditions the person might be electrocuted.
This is a fairly costly repair and a new wire will need to be run to the panel to make it safe.
The next logical question, one might be wondering about is, how did this get to be this way?
Well if you look at the panel you can see it is fairly new looking. The wire in the conduit to the panel is old looking. The original panel used to be a 120 volt panel—which would have only required two wires—one hot and one neutral. Someone, at some point, wanted 240 volts at the panel location so they merely commandeered the neutral wire and made it a hot conductor–unaware (apparently) that they also needed a third wire to make everything safe for the 120 volt circuits that needed a neutral wire.
They have lost control of the electricity and it will make up its own mind where it wants to go.
Not a good plan.
By Charles Buell, Real Estate Inspections in Seattle
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