Sure, unshielded wire is not used in walls.
But in conduit its fine, right?
THHN in conduit was used in the installation of my EVSE in the garage. At the time, I did not consider AL wire. But it sounds like with a junction box, AL wire would have been a copper THHN replacement.
Since you are the electrician, I'll defer to you.
In my mind, dimming of lights means the voltage has drooped. The voltage drooping is due to power lost in the wiring. This could be due to undersized wires with a load which might match the circuit breaker. The current just needs to be high enough to cause excess power lost in the wiring. This doesn't necessarily mean the circuit breaker will trip.
Um. I troubleshoot electronics (not electrical) hardware for a living. Dimming of Ye Lights: What Could Possibly Be Going Wrong?
- Wires are screwed down in a breaker panel, on the meter, and (I don't know how it works out to the pole..) and maybe up to the transformer on the pole. Any wire that's loose may have incidental contact most of the time, but run high current, the deltaV = R * deltaI, and there you are. The fun part: where in the (probably) three or five places that the current's passing through is the near-open? Additional fun fact: When Large Electric Motors start up, they often draw a lot of current, which then reduces as the motor gets up to speed. Yeah, AC compressor/blower motor, I'm looking at you!
- The above is straight electrical connections. Basic rule: If something can move, then it's more likely to break. That includes breakers. Most breakers of which I'm aware have a heat-sensing element that expands when Too Much Current flows, tripping the thing. There are others that use teeny magnets in there, no heat. The heat guys flex under normal operation (i.e., when that blower starts up). Any flexing, over time, causes metal fatigue. It might take decades, but thermal breakers do wear out. Now, if the resident electrician on this thread thinks that the "normal" failure mode of such a failing breaker is simply to trip, far be it from me to argue: He's the expert. But then we're back to #1.
The problem with #1 above is Big Voltage Drops means Power Dissipation. And Power Dissipation means that Things Will Get Hot. In the electrical world in general, Hot Things are very much to be avoided. Now, nifty, short, droops.. I can make a half-a$$ argument that if it doesn't last too long, all those big copper conductors will carry the heat away. And the little guy screaming in the back of my head is going, "Until it Doesn't!" Don't risk your life and those of your loved ones please: Find out what's going on and Get It Fixed.
Finally: As I said, I'm not an electrician. But One Day, when helping a Real Master Electrician on a kitchen reno, we ended up replacing the breaker panel in the house I lived in at the time. I played the idiot assistant: Just competent enough to hand the Real Guy a screwdriver when asked. (He was my neighbor. Yes, I paid full freight.)
So, why were we replacing this breaker panel? Because it had been made by Federated Pacific. Who was Federated Pacific? A company whose breaker panels tended to catch on fire in the presence of an overcurrent or surge. And, after our reno, the house wouldn't get a certificate of occupancy unless that particular panel was gone, gone, gone.
One last thing. As the electrician was removing the individual breakers from said panel in prep to getting the whole thing out, he would reach over to unplug a breaker with one hand. Before doing the deed, he would then turn away from the panel, put his left arm over his eyes, then pull the breaker out. I watched him do this three times, at which point it occurred to me that if a Master Electrician was Doing That, why the heck wasn't I doing the Same Thing? And henceforth copied the man
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