Dedicated Line Noise Filter?

lak

A friend suggested the 5 KVA because he knew it was large enough for most audiophiles systems

5KVA works out to 5000 watts - assuming you have a good power factor. That might be sufficient for a small system, but obviously undersized on even a 15A line.

almarg

Lowrider, my understanding is that a sub-panel should have hot, neutral, and safety ground all wired back to the main service panel

lowrider57

Al, that's what I thought. I asked the electrician about code, and he said it meets code and this is how he wired his house for a high-end HT system. He said not having a ground wire back to my circuit box containing old, poor quality wiring would cut down on noise.

I'm certain this does not meet NEC and I'm with Al that this creates a safety hazard. @lowrider57 did you get construction permits for this project? Was the work inspected by your town's electrical inspector?

lowrider57

... In Philadelphia, a permit is not required for an electrical addition or upgrade in a residence.
The law states that an inspection is required at the time a house is being sold.

Sorry, but you’re mistaken.

" Electrical permits are required for the installation, alteration, replacement or repair of electrical and communications wiring and equipment within or on any structure and for the alteration of an existing installation. "

see: https://business.phila.gov/electrical-permit/

That your contractor didn't know this - and didn't insist on applying for the required electrical construction permit - raises questions about his competency, and whether he's even licensed to perform this work.

lowrider57

The company that I use has about 20 electricians on staff. They come to the house to give a free estimate, then return about a week later to do the work. Perhaps they get the necessary permit before starting the job.

The permit is held by the property owner or occupant, not the contractor. When the work is complete, the project should be inspected in accordance with the permit, and an approval sticker affixed at the site. If you don’t have these permits and stickers, the work was not done in compliance with your local code: Code requires the permit and inspection.

Please don’t take my word for this - contact your city’s construction department for details. And while we're at it, please share the name of the electrician you've been using.

jea48

I would be willing to bet, in most States electrical permits are not pulled for the limited type of electrical work lowrider57 had done in his home.

We have different definitions of "limited electrical work." the OP had " 2 dedicated lines installed ... They originate at a sub-panel off the main circuit box. The sub-panel is connected by the hot lead and has it’s own ground including a second grounding rod." My electrician would insist on a permit for this.

Just because an electrical permit was not pulled, may not have been pulled, does not mean the electrician did not install his work and use the proper materials to meet NEC, state, county, and or city, electrical codes.

That depends on the jurisdiction. Where I live, code requires a permit and inspection; licensed contractors can face substantial fines for failing to obtain a permit first. And the details about the OP's installation suggest that the work itself - because of the grounding - does not meet code.

Safety aside, I'll tell you why this matters. Where I live, when an offer is made to buy a property, closing attorneys routinely file under the state's open public records rules for copies of the property's construction permits. The attorney then gives copies of those permits to a construction expert - often a licensed sub-code official - who performs an inspection of the property on behalf of the buyer. If the inspector determines that work was done without proper permits and inspections, it's a huge red flag that can not only delay a sale, but require that permits and inspections be done after the fact. Was electrical work done behind Sheetrock that's now been sealed and painted? The electrical inspector can insist that the wall be cut open to reveal the work and prove that it was done in compliance with code.

There's simply no good reason to not file for the permit. I'd never use a contractor that would seek to avoid a permit and a proper inspection of his work. It's cheap insurance for the homeowner.

gdnrbob

Your electrician probably did everything to code.

We already know that he didn't follow code. The electrician didn't get the required construction permit and the project wasn't inspected by a city official before it was put into use.

lowrider57

If the subpanel (containing breakers for 2 lines) takes a feed of hot, neutral, and safety ground from the main panel, are these 2 new lines truly dedicated?
  IOW, by tying in to the main panel (which may have shared neutrals and grounds), is there a chance of causing a ground-loop in the new lines originating from the subpanel?

Yes, that is how a subpanel should be wired. Provided that the lines go directly from the subpanel to the receptacle used by the components, those are considered dedicated lines.

Tying the neutral and grounds together at the main panel is required by code and helps prevent ground loops.