What a freaking waste of time and money. None of these people will find anything wrong, because from their point of view there is nothing wrong.Qualifications of the electricians? Years of experience in troubleshooting?
Multiple electricians have failed to find anything wrong with my electrical system or electrical panel.
Exactly. There is nothing wrong. Sorry, but there just isn’t.
Were the electricians just residential electricians, or journeyman electricians with years of hands on practical experience troubleshooting electrical problems in commercial and industrial facilities? Yeah, it makes a difference.
Here is what an average electrician should do, and check for, in an electrical panel.
1) check voltage. Line to Line and each Line to neutral. He/she should also check Line to EG bar voltage to verify the Main Bonding Jumper is effectively bonding the service entrance neutral conductor to the metal enclosure of the panel.
2) Hopefully the electrician has a Thermal Imaging Camera to check for corroded and or poor electrical connection hot spots. Or maybe he/she just has a cheap temperature sensing handheld device for checking for hot spots. (All loads should be turned on if possible. Especially high amperage usage loads).
Corroded and or loose connections can cause series light arcing which in turn can cause harmonic distortion on the mains. Even bad seating contacts in a breaker(s) can cause harmonic distortion on the mains. That also goes for the Main breaker. Same goes for the Line side connection of the breaker to bus tie connection.
Did any of the electricians have the equipment to test for temperature hot spots MC?
3) If no hot spots are detected the electrician still should look for any signs of corrosion at all wire to breaker terminations. Especially on the service conductors feeding the main breaker or main lugs, if the main breaker is elsewhere. You would be surprised how many service entrance conductor terminations at the electrical panel show signs of corrosion.
4) The electrician should check the Grounding Electrode System for corrosion and tightness of all connections. (Grounding electrode system is the wiring and clamps used to connect the service entrance neutral conductor and service equipment enclosure to mother earth.
5) If the panel is fairly old and has aluminum bus the breaker to bus tie connection should be checked for possible burn arcing hot spots. Especially known loaded branch circuit breakers.
Go through all the electrical connections in the panel for wire to terminal tightness. Conductors to breaker terminations. Neutral conductors to neutral bar terminations. And EGC to EG Bar terminations. Check tightness on service entrance conductors at main breaker or main lugs. Check service entrance neutral conductor lug for tightness.
FWIW I have read at least 4 threads on various audio forums over the years where the OP asked basically the same questions as the OP on this thread. In the end the problem was found in the meter socket of an overhead fed electrical service.
Rain water over the years can find its way through the weather head and inside the mast conduit and travel down the conductors and collect on the Line side of the termination lugs. Over the years the water causes corrosion and causes the connection to deteriorate. That in turn causes a small amount of series arcing in the connection(s). That in turn causes harmonic distortion on the mains. The greater the connected load on the corroded connection(s) the greater the percentage of harmonic distortion on the mains.
It won’t cost the OP a PENNY to call the Utility Power Company. Just a little bit of his time.
Or just take the advice of MC. He will tell you "He is the only one here that has actually done it".....
Best regards......