Thread: What is normal for house voltage?

Originally Posted by doughboyshredder

Ehh, no.
Lights aren't flickering because they are on the same circuit.

If there is too much of a load on the panel the additional load can draw the voltage down across the entire panel. Too much of a load, can be caused by a loose neutral, or too small of a service for how much of a load there is at the house.

Too much load is caused by too much shit you plug in at your house. If you draw too much over current for your main breaker it will trip not cause your lights to flicker. Believe it or not loose neutrals are more caused by cars and trucks driving by your house. The vibrations through the ground plus whatever you do in your house. Walking around. Cars in and out of a garage, etc.

Before the plugged in loads cause an overload of your whole house (200 amp service?), they will affect the circuit they are on, most likely a 12 gauge 20 amp circuit. Having said that, it is common to see lights flicker at the instance a large motor load turns on. The odds are the dimming lights are more due to the skill saw's inrush current t as opposed to too many cell phone chargers and lights on. and As any electrician knows, various factors will lead to voltage drop (what causes your light to dim if you do not have a loose neutral). Key things are the load in amps, the wire type, and the length of the circuit.

Unlike what DBS said, a loose neutral is a high resistance factor which impedes amperage flow. A loose or cut neutral in a shared neutral circuit (branch or service) can result in low voltage on some appliances while others see a higher voltage.

I was leaving out the details, which you added rather well.

After a little more investigation it looks like its only the dining room light that's dimming when the central air kicks on. They're on the same breaker, which is 20 amp, 120 volt. My guess is that it's just overloading it when it kicks on. I don't think it's something I need to worry too much about, but I'm no electrician.

And RShea, what are your thoughts on a UPS unit that actually conditions power, like the APC Smart series? I have one of the less expensive ones that just goes to battery when the voltage gets strange or I lose power. It causes my Corsair power supply to buzz when it's on battery. I'm told that's not an issue, but I'm always paranoid about losing data.

Originally Posted by doughboyshredder

Ehh, no.
Lights aren't flickering because they are on the same circuit.

If there is too much of a load on the panel the additional load can draw the voltage down across the entire panel. Too much of a load, can be caused by a loose neutral, or too small of a service for how much of a load there is at the house.

i didn't read the whole thread. i've noticed a lot of houses don't have dedicated circuits for things they are supposed to have dedicated circuits for -- basically what rshea said right above you. and yes, it does cause things to flicker if the lights are on the same circuit when those items kick on.

Originally Posted by spook

i didn't read the whole thread. i've noticed a lot of houses don't have dedicated circuits for things they are supposed to have dedicated circuits for -- basically what rshea said right above you. and yes, it does cause things to flicker if the lights are on the same circuit when those items kick on.

Yeah, you're absolutely right.
I forget that not everything is wired properly.
AC should be on it's own circuit absolutely. I thought he had stated that all of the lights in the house flickered when the AC kicked on.