Frank Cox wrote: > > Electrical regulations vary substantially from place to place even within the > same area. I have electrical inspectors (gas inspectors, fire inspectors, > health inspectors, boiler inspectors, inspector inspectors I suppose) go > through my theatre on a regular basis. One of those guys told me that it's > illegal to use an extension cord in commercial building in some cities around > here. Not in my city, though -- I had never heard of a restriction like that > before. > For a lot of places, this is a fire regulation violation, and not an electrical code violation. There are a couple of problems with using extension cords. One of the biggest is that it is too easy to damage one if you do not have it routed properly. Another problem is that too many people use a cord that is too light for the job. Extension cords come in different gages. There is often a chart showing what gage cord is needed for what type of load, and what distance. And you can really run into problems when you string then together. For example, if you have 2 16 gage, 100' cords strung together, you can short out the cord, and not trip a 20 amp breaker. The resistance of the wire is enough to limit the current. It works well when you need to free up a cord frozen in the snow. You can sometimes do it with a pair of 50' cords as well. You also run into problems whey you start connecting motor loads. Something like a small refrigerator or dehumidifier can cause real problems. They may work fine under normal usage, but the first time the power is interrupted when they are running, and then comes back before the head pressure has bled off, you will have problem. The motor can not get enough power to start under load, or to trip the breaker, so it sits there, drawing the maximum power the cord will provide, all the while the cord is acting as an electric heater until it burns up, possible starting the building on fire. Also, the ban may not be on all extension cords. It may allow appliance extension cords. These are normally 12 or 14 gage wire, and are fairly short. This means they can carry enough current, and are less likely to be subject to physical damage. Oh yes, cords are not allowed to be run through walls, ceilings or floors. They are not allowed to be run in ceilings, nor where subject to physical damage. This one reason that you see the metal peace covering cords that have to cross a traffic area. (walkway) The other is to prevent people from tripping on them. Mikkel -- Do not meddle in the affairs of dragons, for thou art crunchy and taste good with Ketchup!
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