A recent event has made a few of us aware that refreshing our knowledge about electricity is a good thing. While working on a live-fire house burn preparation, I was confronted with the main panel in the basement that was in the way, making it difficult to put up a ceiling covering near the burn pit. Before starting our preparations, we were told by the contractor of the company that donated the house that the power to the house had been cut. I proceeded to pull lots of wires from the panel, cutting as I went. The last to be cut was the main feed from the powerline that fed into the panel (240 volts). We all know what happened when my sawzall blade went through the galvanized conduit and cut into one leg of the power… a loud, scary “pop” and a shower of sparks! Fortunately I was protected by a well grounded electrical tool but my blade had two big chunks blown out of it. We immediately called the contractor and then the local power company (Puget Sound Energy). PSE had no record of a request to cut power to this house and showed that the house did indeed have power to it (no kidding!). A lineman from PSE immediately came out and cut the power to the house so we could continue or preparations for the upcoming training.
While the PSE lineman was there we asked a lot of questions. Here are a few things I felt that were important to remember. 1. DON’T TAKE THE CONTRACTORS WORD ABOUT ELECTRICAL ISSUES. They may think that no power to the house means shutting down the main breaker. Obviously this isn’t the case. The house is not energized only when the power company tells us it is not energized. They are the only ones who can completely cut the power to a house or business. 2. If there is an overhead powerline running to the house and there is a meter on the house (even though the indicator wheel is not moving) the house has power running to the meter base. To confirm, there is a number on the meter. Call PSE and give them this number. They can tell you over the phone if the house is energized or not. Note: If there is a meter base but no overhead power lines, extra caution should be exercised as the house could be supplied by underground power. 3. Meter bases can become energized! If you are called to lights flickering inside the home or smoke smells in or around a meter base, DO NOT TOUCH THE METER OR THE SURROUNDING METAL CASE!! The lineman stated that the cause is arching or shorting inside the meter base/housing due to faulty or failing connectors. Touching the metal housing can cause an individual to become energized. He also stated that looking at the glass of the meter may show smoke on the inside. This is a good indicator that something bad is going on inside the meter housing. Call PSE. 4. If the meter has been removed, there is no power to the structure. NOT TRUE! Businesses and some residential homes with shops that have 3 phase/240 volt service can continue to be energized with the meter having been removed. Be aware of what you are looking at. If you aren’t sure………..Call PSE. Thanks for listening. Let’s stay safe.