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Electrical panel emergency disconnect, ground rods and sound quality

I finally pulled the trigger on upgrading my house old electrical panel (load center) setup that wasn’t properly grounded.

I went with the Square D QO series panel, whole house surge protection and 2x8' ground rods and 4ga solid copper ground cable per NEC code. My electrician drove ground rods at a 7' distance between them per code. I learned too late that there is a recommendation for optimal distance between ground rods to be about 2x the length of the rods. Oh well...

Even so, I could clearly hear improvement in my system and it was not subjective. I no longer hear a transformer-like buzzing noise coming from my speakers that would increase with volume. Instead I hear a much softer noise similar to an AM radio being tuned. I have to be right next to tweeter and volume up pretty high to hear it. I’m sure that noise was always there but masked our before the upgrade.

City inspector, however, faulted new panel install for the lack of an outside emergency disconnect between it and the meter per NEC 230.85. My electrician thinks it’s completely unnecessary and that requirement will be done away with in the next NEC revision, but I digress.

Is there an opinion about which brand/type of emergency disconnect has the least negative effect on the quality of power coming into the house?

How much my ground effectiveness has been reduced by having distance between ground rods be less than 2x their length?

All in all, I highly recommend this type of upgrade for older electrical systems!

dmk_hifi
bikeboy52
184 posts
 

That 230.85 was only added a few years ago why would take it out?

dmk_hifi OP
61 posts
 

My electrician believes it’s because 2020 code puts disconnect between meter and electrical panel, whereas it really belongs between meter and the provider. Just like gas companies have it. Intent for the disconnect is to allow emergency services to cut off electricity for safety, but with the current spec you still have live electricity at the meter even after cut off. Personally I think it puts undue expense on homeowners and allows pranking teens easy access to your whole house electrical shut off. 

jea48
4,303 posts
 

@dmk_hifi

Plain and simple your electrician didn’t look at the code changes for NEC 2020 edition from the previous 2017 edition.

The Emergency Disconnect is for the fireman’s safety when entering a house if there is a fire.

As for there still being live power at the meter that is not a safety issue for the fireman. If the fire has burned over and or around the meter socket the Utility Power Co is called and the power is disconnected from the dwelling unit.

Power Companies do not allow a disconnect ahead of the meter socket for a residential dwelling unit. Sequence is meter >> Switch >> Fuse.

As for securing the EM disconnect on the outside of the house there is a provision on the enclosure for installing a Padlock that secures the outer metal cover. The Fireman has a master key for all Padlocks made... It called a bolt cutter.

The AHJ (Authority Having Jurisdiction) has the final say. If the electrician is arguing with the inspector he is only digging the hole deeper. I hope you got a contract price from the electrician for doing the job...

dmk_hifi OP
61 posts
 

Jea, thanks for your breakdown, that’s helpful.

Installing disconnect will be an extra charge to me, but due to this hassle with the inspection he is giving me a discount on the job. 

So based on what I’ve learned and with your post, I will bite the bullet and install the disconnect. I really want this work to be permitted officially for when it comes time to sell the house.

Is there a disconnect brand/type that you prefer?
Should I bother with changing distance between ground rods?

Thanks for your help guys.

erik_squires
15,788 posts
 

Whatever may happen in the future, the emergency disconnect requirement is pretty open and shut.

Having it after the meter makes perfect sense to me too. Don’t get scammed.

If your AHJ is using the 2022 NEC you should have gotten mostly CAFCI breakers as well.  The city inspector should have checked for this as well as appropriate.

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