How To Do You Measure the Quality of Your AC Power?

They tested the line from the street to my meter. I don’t know what they tested exactly. Is that the same thing?

They tested the line from the street to my meter. I don’t know what they tested exactly. Is that the same thing?

At our place, the power quality survey took four weeks. They installed a special meter at our service panel from which they downloaded data once a week for four weeks. The initial visit entailed checking the voltage on the lines, checking the connections at the service panel and power pole, and testing continuity of all the breakers.

So, not the same thing.

mkgus OP281 posts

08-31-2021
10:57am


Quick update: I called my utility company and they sent someone out immediately. They discovered that the neutral lug on the homeowner side of the meter was loose and the bolt is stripped. An electrician is on the way to replace the neutral lug.

@ mkgus

Well a loose service neutral in the meter socket could cause problems. Though there is an alternate current path connection from the Line side neutral conductor connection ’IF’ metallic conduit is used for the service wiring from the meter socket to the main disconnect service equipment panel. The neutral bus in the meter socket is bonded, bolted, directly to the back of the metal meter socket. And IF all the conduit fittings and locknuts are tight and solidly electrically connected together the conduit will carry the unbalanced load current from the neutral bar in the main electrical panel to the Line side of the meter socket service neutral conductor. (Neutral bar in the main disconnect electrical panel is bonded, connected, to the panel’s metal enclosure.)


Example of a 1 phase 120/240V 200 amp meter socket. The neutral bus and lugs is located in the center of the socket. Note the bus is bonded, bolted, directly to the back of the enclosure.
https://www.homedepot.com/p/Milbank-200-Amp-4-Terminal-Ringless-Overhead-Underground-Horn-Bypass-Met...

Now if you had said the top neutral lug was stripped causing the Line side service neutral to be loose that could/would cause big problems. You would have noticed while some incandescent lights would dim others would burn brighter. You would have also been replacing the brighter lit light bulbs more often. You also could/would have problems with 120V appliances with motors. Like the refrigerator, washing machine, and such. Even small electronic items failing due to being fed by a high overvoltage.

Here is a video that shows how the secondary of a split phase 240/120V power transformer works.
https://www.youtube.com/watch?v=eVamt9IdQd8

I don’t remember if you said the electrical service is fed overhead or underground.

It’s fed underground. 
Another update:

The electrician came out and repaired the bad neutral lug and tightened everything up. The utility turned the power back on. The first thing I did was run some “tests.” Dimmable lights that used to buzz loud are quieter, the treadmill no longer dims the lights with each footfall (it does a little bit but it seems normal now whereas before it was like being at a rave), and best of all the sound quality of my audio system improved! No wonder - I’m sure the current flowing through the bad neutral lug wasn’t helping in any way with power delivery!

I’m really glad I put in the effort to follow through on this. I am very thankful for all the good advice from this community! I knew something was wrong with the power. I am happy that I didn’t go off on tangents with dedicated lines or power regenerators. I still plan on doing those things, but they would not have completely solved my problem in this case.