Whole House Mains Wiring -- Ping: Jea48 (Jim) -- & ALL Others for your HELP!


I had the following PM discussion with member Almarg.  As you can see he -- as always -- was quite helpful!  However, upon my suggestion to post our conversation for others to see and perhaps learn, Al readily concurred, but suggested for the questions that he couldn't address, he referred me to Jim [Jea48].

It should be noted that I drug my Atma-Sphere amp manufacture, Ralph Karsten into this conversation via email.  As generous and helpful as he always is, he too helped a bunch.  I haven't copied his single email because the below is complex enough, without adding more.

My hope is that where my assumptions are questionable or for my questions, others will respond.  

Our new house's rafters are about 50% installed, so the other trades will be in soon.  And I will have to soon inform our electrician of our needs.  But I don't want to request something that isn't needed.  More IMPORTANTLY, I don't want to MISS something that is NEEDED!  So your help in checking this thread is greatly appreciated! 

NOTE:  I've listed our conversation as Audiogon would -- the most recent post last.  So, the real important part for me, is getting answers to the set of questions I asked towards the bottom -- Today at 20:28!!

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mrmb (you)

January 27, 2018 23:49

Thanks Al! That's what I was seeking.

Speaking of electrical noise/hum, I just found a Martin Logan article speaking about pre-wiring https://www.martinlogan.com/learn/faq-prewiring-a-home-theater.php.).

It addresses one of my other concerns about inserting multiple dedicated circuits in one room. They advise to connect all outlets/circuits with the same ground wire. I've previously read that ALL audio components should be connected together -- i.e., on the same dedicated circuit. If one didn't tie 2-dedicated circuits together by using the same ground, I can see why I've seen that advice.

Have a great remainder of the weekend AL. And thanks for sharing your expertise on Audiogon and in this PM. It's appreciated!!

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almarg

January 28, 2018 13:37

Hi Mike,

 Thanks for sending the link to the article, which I hadn't seen before. A couple of comments on it:

 1)As you appear to realize, the benefit of the single ground wire approach they advise is that it would minimize or eliminate any differences of potential (i.e., voltage) between the safety ground connections of the outlets for the various dedicated lines, and hence any differences in potential between the chassis of components that are interconnected in the same system but are powered by separate dedicated lines. Which in turn will avoid ground loop issues that might otherwise occur.

 2)If the electrician indicates that such an approach would be problematical, due to either practical considerations or code compliance issues, using 3-conductor Romex (e.g., 12-2 with ground) for each of the dedicated lines should come close to accomplishing the same thing. And could very conceivably provide results that are just as good.

 In 3-conductor Romex the safety ground wire is symmetrically placed between the hot and neutral conductors. Therefore voltages that may be induced into the safety ground conductor by the magnetic fields surrounding each of the two current carrying conductors [current flow in a conductor produces a magnetic field around that conductor] will tend to cancel, since the fields produced by the two current carrying conductors are in opposite directions.

For further explanation see pages 31 to 35 of the following paper, which was written by a renowned authority on such matters:

https://centralindianaaes.files.wordpress.com/2012/09/indy-aes-2012-seminar-w-notes-v1-0.pdf

Best regards,

-- Al

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mrmb (you)

January 28, 2018 20:28

Hello Al,

RUN LENGTHS/BALANCING:

I did recently find elsewhere as you suggested, that using 12/3 was a prudent approach, but thanks for seconding that approach.

We talked about Martin Logan’s single ground wire recommendation. And you mentioned that using 12/3 (verses 12/2) may well compensate, if code prevents the implementation of ML’s plan. I suppose if code allows the M/L single ground wire approach and then 12/3 is also used, that would be icing on the cake!

Because it’s a breeze to do while the walls are open, I believe I will put 2-20amp outlets in the most important room – the 2-channel one (just in case)! Residing therein will be: 1) Atma-Sphere MA-1 monoblocks; a Lampizator Golden Gate DAC and 2-Soundlab M1PX stats.

For now let’s ignore the Soundlabs, which will be about 7 feet from the rack and that wall’s outlets, and thus, probably on their own 15amp circuit. Would you recommend that the Atma-Sphere amps be plugged into 1 of the dedicated 20-amp outlets and the Lampizator plugged into the 2nd. 20-amp circuit? Or would it be better to plug all 3-pieces into the same 20-amp circuit (plugging the Lampizator into an additional receptacle on the same circuit)?

Ancillary to the question of what component(s) should be plugged in where: Would there be any sonic downside to installing a Wall-Switch for the 2-Soundlab’s dedicated line (and its ganged outlet on the opposite side of the room)?

That is, would a Wall Switch be some sort of sonic negative; because it was a part of that circuit (sonically deducting a positive, or adding a negative)? And referencing the Martin Logan’s single ground wire plan: I’m unsure if we tied 3-dedicated circuits together (both 20-amp ones and the 15-amp Soundlab one) with a single ground, if a Switch would prevent that process from being implemented? Or would a Switch somehow negatively affect the “single ground logic”, or simple be too cumbersome to install?

Lastly, if code will allow M/L’s method of using a single ground on all dedicated circuits for my room, it may be difficult to implement because of the distance the Soundlab's (7-Feet) are from the front wall outlets. Especially when considering that the Soundlab’s outlets will be 19-Feet from each other – on opposite sides of the room.

My concern may be unfounded, because being the neophyte that I am; I can’t envision how to implement a single wire ground for 3-dedicated outlets as far apart as mine will be. And overall, I wonder if would be good enough (in audiophile terms) to simply install 3-dedicated circuits and not be concerned with using the same ground for each? However this may be confounded by the fact that folks have suggested that if multiple dedicated circuits are used, one should make the wire length for each one as close to the same as possible. Without rolling-up and storing several feet of cable (in the walls or at the panel) for the circuits longer that the other’s, this would be all but impossible.

I apologize for my hyper-granularity or should I say my “analness” regarding this wiring issue, but that’s sort of the definition of we audiophiles isn’t it? At any rate, I appreciate your assistance in a topic that I’m flying blind on! After we’re all said and done here, for others to gain from your teaching, I would like to post our communications on Audiogon as long as you’re amenable to same. That’s the beauty of forums, many sharing/learning from ONE!!! But I digress…..

WIRE:

The plan is to specify Southwire’s Romex ® brand of Solid Core (vs stranded) wire – is Southwire Solid Core also your recommendation? But I’m confused about the type of Romex ® to use. I’ve seen various ones: with “XHHW” recommended over “THHN”, but also “NM” recommended. What say you?

WIRE GAUGE, MULTIPLE OUTLETS:

Additionally, I've found a piece posted by MSB to be informational. As you can see (http://www.msbtechnology.com/faq/how-to-wire-your-house-for-good-power/) their thesis is that gauge size is of utmost importance! I’ve found some disagreement relative to whether 8 gauge wire can be installed in an outlet or not -- your opinion? At any rate, can an electrician pull 8 gauge to the audio room and terminate it in some sort of junction box and go from there to my audiophile grade outlets? And then, is there any downside to ganging several outlets from one dedicated circuit? In my home theater area, rather than multiple wall outlets, I’ve found it more advantageous to use a power center such as the Furman Elite-20 PF I’m presently using. It has a video and a sonic benefit, plus I find DC Triggers to be useful. So, unless you believe ganged outlets are better than a Furman (et al), I won’t have the electrician install anymore outlets than I think will be needed when using a Power Center.

PANEL-TO-PANEL WIRE GAUGE AND CONNECTION METHODOLGY:

Should I recommend a specific wire gauge or type for the electrician to use BETWEEN the main 200-amp panels and the sub-panel? Should I ask the electrician to use a specific method to use to tie these panels together? One forum poster advised: “running one large wire from the very top position in the load center on the leg with the least number of noise-generating devices to a sub-panel”. Would this be your method?

BREAKERS:

I also found the following discussion from PS Audio (http://www.psaudio.com/ps_how/how-to-install-a-dedicated-ac-line/). It advised that 20-amp breakers should be used “for even the lowest draw source equipment feed”. I took that to mean that although the circuit may be less than 20-amps, that a 20-amp breaker should be used. Is that what you would suggest?

LOAD CENTERS:

So, my present plan for the 2-channel room (mentioned previously) is to install 2-200 amp panels and a 60-100 amp subpanel for the 3-A/V areas (to get it as close as possible to 2-channel audio room – is this your preference?

Speaking of load centers, I’ve found several positive mentions of Schneider’s Model: “Square D QO” Panels (the “QO” Model with copper plated busing). Does QO Square D model work for you?

GROUND ROD:

I’ve read rather lengthy dissertations on this subject. Not being interested in getting into the weeds here, is there a material, length and methodology you would suggest using here?

SERVICE:

And lastly, should I even be concerned about the wire/cable used for the service drop or service entrance? NOTE: Service will be buried.

IT’S ABOUT TIME….THE CONCLUSION:

Whew, I can’t tell you how much I appreciate you wading through all and helping with all of this!! It’s all but impossible to find folks educated in this subject such as Electrical Engineers and Electricians who care about the details we audiophiles do! So, I consider you a wealth of information on the subject form your previous responses to my questions but more importantly, from the number of posts and volume of information that you’ve posted on Audiogon and I’m sure elsewhere!!!

Be well and take care,

-Mike

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almarg

January 28, 2018 22:06

Hi Mike,

Thank you again for the nice words.

I should have been more explicit when I referred in the previous communication to "3-conductor Romex (e.g., 12-2 with ground)," and subsequently to "3-conductor Romex." My reference to three conductors included the ground conductor, so I was referring to "12-2 with ground" and not to 12-3. The additional "hot" conductor in 12-3 would serve no purpose in this situation, and if that conductor were used to carry a current the benefit of the symmetry I referred to between the current conductors and the ground wire in 12-2 would likely be negated.

My suggestion of 12-2 Romex as a potentially suitable alternative to ML's suggested configuration was in contrast, for example, to using conductors within metal conduit, which as explained in the reference I cited would be much more conducive to ground loop issues. Especially when multiple dedicated lines are used to power the components in a single system.

Regarding your first question, my guess is that it would be best to put the amps and the DAC on separate circuits. I say that in part because various comments I've seen Ralph provide over the years lead me to believe that his designs are less susceptible to ground loop issues than most, and consequently there is unlikely to be any downside from keeping the amps and the DAC with its potentially noisy digital circuitry on separate dedicated lines.

Regarding a wall switch for the power to the speakers, I don't see that as being a negative in itself. However as you alluded to the considerable distance between the various outlets does sound like implementing the ML approach would be cumbersome at best. And perhaps more significantly the considerable length of the ground connection between some of the outlets may negate a lot of the benefit of that approach. So perhaps just using "12-2 with ground" Romex in the normal manner, for each of the dedicated lines, would be simpler, more practical, and provide results which are just as good.

Regarding the suggestion of keeping the lengths of all of the dedicated lines the same, which I too have seen stated a number of times and which the ML writeup implied is desirable, FWIW I am not a believer in that. In nearly all applications the different lines would be carrying very different amounts of current, and correspondingly their conductors would be surrounded by magnetic fields having very different strengths, resulting in very different amounts of current being induced in the ground wire. Not to mention that voltage drops in the hot and neutral conductors would be very different. So I don't see why keeping all the lengths the same would provide any benefit.

Regarding posting our communications in the forums, that would be fine with me. If you were to do so, or at least start a thread with some of your questions, chances are it would catch the eye of Jea48 (Jim), who is by far the leading expert at Audiogon on electrician-type (as opposed to EE) matters.

And for that matter, Jim would be the best person to address your questions about NM-B vs. XHHW vs. THHN, use of 8 gauge wire (which I suspect would be extremely difficult to work with, as well as probably being overkill), and most or all of your subsequent questions.

Regarding the question about PS Audio's statement that "we recommend you use a 20 amp breaker for even the lowest draw source equipment feed," though, I can say with certainty that it would be both unsafe and a code violation to use a 20 amp breaker on a circuit which "may be less than 20-amps." In other words, if a 20 amp breaker is used the outlet must be a 20 amp type and the wiring must be 12 gauge or heavier. What they no doubt meant, as you probably realize, is that even if the equipment powered via that line only draws a small fraction of 15 amps, they would still recommend a breaker, outlet, and wiring rated for 20 amps. Which would have no downside, and I suppose might provide at least a small benefit in some circumstances.

Best regards,

-- Al



128x128mrmb

Showing 10 responses by jea48

@almarg,

Al, thank you for the kind words.

+1 on the information you gave mrmb. I would add 2 wire + ground MC (Metal Clad) aluminum armor cable has a lower "Ground Voltage Induction (GVI)" than 2 wire + ground NM-B sheathed cable does. (Romex  is a Trade Name of NM-B)

 Solid copper 10/2 with ground MC aluminum armor cable.
https://www.homedepot.com/p/Southwire-10-2-x-125-ft-Solid-CU-MC-Metal-Clad-Armorlite-Cable-69117005/...

Jim 
@mrmb,

I am still working on a reply to your long posted message. You asked a lot of different questions.

In response to your last post.
Thanks Jim: To make sure I got it, the lower GVI of MC aluminum clad a negative and thus, supports Al’s suggestion of using NM-B?
No it’s a positive thing. The lower the GVI the better. With that said I would say the majority of dedicated branch circuits installed for audio equipment is NM-B cable using plastic rough-in wall outlet boxes though.

If you use NM-B cable for the audio/video dedicated branch circuits there are a few installation guidelines that should/must be followed.

I assume the house will not have a basement or crawl space. You said in a post the branch circuits will be installed above the ceiling joists/rafters/attic space area.

1) * Each NM-B cable needs to be installed separated by at least 12" from any other parallel run branch circuit wiring. More than 12" is better yet. If the parallel ran dedicated branch circuit cables are not kept separated from one another, as well as other parallel branch circuit wiring, the magnetic fields of the AC current carrying conductors can/will induce a voltage onto the equipment grounding conductors of the other cables. This can cause ground loop hum problems. The induced voltage can/will also transfer AC noise (EMI/RFI) from one cable to the other. Dedicated branch circuit NM-B cables must be kept separated from one another as soon as reasonably practicable after existing the electrical panel all the way to the drops down the wall stud cavity to the wall rough-in boxes. That includes keeping the dedicated circuits rough-in wall boxes separated from one another by at least 12" or more.

* * * EDIT:
 Depending on the location of the sub panel to the room, the dedicated branch circuits will be installed, it is possible the electrician could install the dedicated circuits entirely through individually separated bored holes in the wall studs. 

2) * MN-B cables should be installed at least 5ft from any ceiling lights / can lights where dimmers, or LED, or CFL lighting is used. That includes load side branch circuit wiring of the noisy harmonic producing items. The nasty, filthy, harmonics will infect the audio dedicated branch circuits if the electrician does not keep the audio dedicated branch circuits away.
https://www.youtube.com/watch?v=OCK5W9vlAE0

3) * Same goes for the sub panel feeder that will feed the sub panel. I assume the electrician will install a 3 wire + ground NM-B cable to feed the sub panel from one of the 200 amp electrical panels. Keep the feeder away from harmonic producing things like dimmers, LED and or CFL light fixtures. That includes load branch circuit wiring.

I’m still confused at to whether we should use NM-B vs. XHHW vs. THHN.
The insulated conductors used in NM-B sheath cable is THHN insulation.
http://www.southwire.com/ProductCatalog/XTEInterfaceServlet?contentKey=prodcatsheet6

XHHW? Single insulated conductors pulled/installed in an empty conduit after the conduit is installed? Are you thinking of having conduit installed?


Any experience with XHHW vs NM-B when used for audio? My guess is that it would be difficult at best, to try to discern a sonic difference between the two (I hate auditioning audio cables; let alone Romex). So why not just USE what’s readily available (NM-B)? Sound like a plan?

XHHW is commonly used in industrial facilities where its’ add heat temperature rating is desired. Because of the tough insulation XHHW also has a high resistance to chafing due to vibration inside conduits, boxes, make up boxes for large motors, and such, where vibration may be a factor. XHHW insulation is tough as steel nails.
XHHW is also used in underground conduit runs for its’ added moisture/water protection properties. It will hold up better in hash environments far better than than THHN/THWN will.
Beats me how it would have any impact on the SQ of audio equipment though.

Here is a pro audio white paper for you to read through.
https://www.anixter.com/content/dam/Images/Logos/Supplier-Logos/Middle-Atlantic/PowerPaper.pdf

Jim

@mrmb ,

Where to start.

Speaking of electrical noise/hum, I just found a Martin Logan article speaking about pre-wiring https://www.martinlogan.com/learn/faq-prewiring-a-home-theater.php.).

It addresses one of my other concerns about inserting multiple dedicated circuits in one room. They advise to connect all outlets/circuits with the same ground wire. I’ve previously read that ALL audio components should be connected together -- i.e., on the same dedicated circuit. If one didn’t tie 2-dedicated circuits together by using the same ground, I can see why I’ve seen that advice.

Electrical code says the safety equipment grounding conductor shall be part of, installed in, the cable with the current carrying branch circuit conductors.

I guess the electrician could tie all the equipment ground wires together with a bonding jumper at all the wall rough-in outlet boxes locations. You would need to ask him if he has a problem with it or if the AHJ, (Authority Having Jurisdiction), Electrical Inspector would have a problem with it.
I am pretty sure, depending on the State and city you live in, the electrician will install AFCI (Arc Fault Circuit Interrupter) breakers in the the load center panel that will feed the new dedicated branch circuits. Connecting all the equipment grounds together at outlet boxes could cause a problem. I don’t know, the electrician might know.
I personally do not see the need to bond all the equipment grounding conductors together at the wall outlet boxes, IF, the proper branch circuit wiring is used and the proper branch circuit wiring installation method is followed for audio/video branch circuit wiring.

Just a guess the electricians that will be wiring your new home are Residential Wiremen. They will follow, meet, the bare minimum electrical safety code required by NEC and the AHJ in your area. That is how the electrical contractor bids the job. You will need to spec and pay extra for any additional materials and wiring methods you want for the audio/video branch circuit wiring. Your wants must meet bare minimum electrical safety code standards for your area. You can exceed bare minimum electrical code standards all you want. It’s what ever you can afford.

My suggestions are based on NEC, (National Electrical Code), standards. The AHJ in your State and or local governing body has the final say.

The main electrical service.
Depending where you live, soil resistivity and severity of lightning storms, the earth connection of the electrical service is very important for lightning protection. In my area I highly doubt any residential electrical contractor checks the electrical service grounding electrode to earth resistance. They just supplement the required ground rod with a second ground rod. That meets the requirement of NEC.

IEEE recommends 5 ohms or less.
NEC says if the grounding electrode to earth resistance is greater than 25 ohms it shall be augmented by one additional ground rod. That’s it, no further testing is required.
https://en.wikipedia.org/wiki/Soil_resistivity

The test must be preformed by someone that has been trained and certified for use of the testing equipment used. I would suggest you hire a well established "Power Quality" testing company in your area. Most large Commercial/Industrial Electrical Contractors can recommend one to you. Price in my area runs around $150 to $200 for the testing. IF additional earth grounding is needed to achieve a ground rod to earth resistance of less than than 5 ohms you will have to pay an electrical contractor to install the additional earth grounding electrodes. Usually more 10ft earth driven ground rods is not the answer. In most cases a 30ft deep driven ground rod will do the job. (Three 5/8" X 10ft ground rods coupled together.) BUT it depends on the soil resistivity where you live.

I think I pretty much covered the rest of your questions in my last post.

I will add if you are going to install a sub panel feed it with at least #4 copper or #2 aluminum wire.

For audio equipment, system, connected together with wire interconnects it is recommended the dedicated branch circuits be fed from breakers fed from the same Line, Leg. All from Line 1 or all from Line 2, not from both though. In your case, If I read you posts correct, you have multiple A/V systems. You could balance the sub panel out by using line 1 for one system, connected together by wire interconnects, and the other system, connected together by interconnects, from Line 2.

If the electrician questions your directions, for feeding the dedicated circuits for each system from the same Line, just tell him the total connected continuous load is less than 16 amps. And the dedicated circuits are intended to be used to feed audio and video equipment only. That should satisfy him as well as the electrical inspector.

Speaking of the electrical inspector, there is a very good chance the electrical code in your area requires "Tamper Resistant" receptacles. Are your audio grade duplex receptacles Tamper Resistant? The electrician will have to install Tamper Resistant outlets for the final electrical inspection otherwise the inspector will Red Flag the job. Not to mention the inspector will chew out the electrician for installing non Tamper Resistant ones, wasting his time on a callback inspection.
I am not going to suggest what you can do after the final inspection an the occupancy permit has been issued.

Dedicated branch circuit wire size for the 2 channel audio equipment? I would install overkill and use #10awg solid copper wire. The breakers will be 20 amp making them 20 amp circuits. For the speakers I would install #12awg solid copper wire minimum, fed from a 20 amp branch circuit breaker.

Type of branch circuit wiring used?
If you choose NM-B use plastic boxes, not ferrous steel boxes. The electrician will use deep plastic boxes for the #10 solid wire. He will need all the room he can get for the #10 solid wire to make up on the duplex receptacle outlet. Ask the electrician to please connect the #10 solid wire to the side terminal screws, by curling the wire clockwise around under the screw head, instead of using the back wire terminal screw plate to secure the wire. The connection made under the screw head will remain tight even as the electrician pushes, forces, the duplex into the wall box to complete the installation.

What are you using for a duplex cover plate?
Avoid low grade stainless steel plates with ferrous materials. It will degrade the sound. Use a strong magnet to check for ferrous materials in the cover plate.

A cheap nylon unbreakable/flexible plate works just fine.

If you use MC cable make sure the electrician buys solid copper conductors and aluminum armor. Yes it can be bought with stranded wire conductors. The electrician would much rather work with stranded #10 wire instead of solid.

Problem with using MC cable is the type of wall rough-in boxes used. I am not a fan of steel ferrous boxes used for the duplex receptacle outlet.

For what it’s worth I installed two 20 amp dedicated circuits, using #10/2 with ground MN-B sheathed cable, that are around 75ft each in length from the electrical panel to the wall outlets for my two channel audio system. The system is dead quiet.

Jim


From the AA post above:
If you run a subpanel, you will put the breaker on one leg. If you run individual lines, it’s best to put them all on one leg. If you vastly oversize your setup (i.e. a 100A sub-panel), and then only use say 12A of that capacity, you’ll be putting an asymmetric load on the legs. An extreme asymmetric load is bad - bad for your appliances, bad for your power bill.

almarg said:

Mike, I don’t understand the AA post you quoted. In the stated example it seems to me that if the load is unbalanced by 12 amps, it is unbalanced by 12 amps regardless of whether the sub-panel is a 60 amp panel or a 100 amp panel.

Best regards,
-- Al
+1

~ ~ ~

A 120V 12 amp load?

What if the 12 amp load was fed from a single branch circuit? What then?

120V loads are changing all the time.

Yes by code the electrician is supposed to balance the electrical panel connected 120V loads the best he can. But he doesn’t know what the home owner might plug into any given wall electrical outlet. How about a vacuum cleaner? Most draw 12 amps.

Sure he can balance the circuits above the counter tops in the kitchen. He can put the circuit that feeds the microwave on a breaker fed from say L1 and the Dishwasher circuit on a breaker fed from L2. If they are running at the same time the two loads are somewhat balanced. What if the dishwasher is running and the microwave is not? Or the microwave is being used but not the dishwasher? Like I said 120V loads are changing all the time. The electrician tries to balance the 120V loads the best he can for the what if....

What you don’t do is move all the know 120V loads like the microwave, dishwasher, garbage disposal, washing machine, refrigerator, deep freeze, sump pump, and any other motor load you can think of to one Line, leg, in the electrical panel, so the other Line, leg, can be used for an audio system that draws maybe 8 to 10 amps tops.



jea48 said:

For audio equipment, system, connected together with wire interconnects it is recommended the dedicated branch circuits be fed from breakers fed from the same Line, Leg. All from Line 1 or all from Line 2, not from both though. In your case, If I read you posts correct, you have multiple A/V systems. You could balance the sub panel out by using line 1 for one system, connected together by wire interconnects, and the other system, connected together by interconnects, from Line 2.

If the electrician questions your directions, for feeding the dedicated circuits for each system from the same Line, just tell him the total connected continuous load is less than 16 amps. And the dedicated circuits are intended to be used to feed audio and video equipment only. That should satisfy him as well as the electrical inspector.
The sub panel 120V loads will be somewhat balanced.
The same if the 2 ch audio room was fed with a single 120V 20 amp branch circuit connected to say L1 and the HT room was fed with another 120V 20 amp branch circuit fed from L2. What is the total connected load to L1? What is the total connected load to L2? What are the chances both systems will be in use at the same time?

~ ~ ~

@mrmb,

Have you considered what you will be insulating the wall stud spaces with in the audio and HT rooms? Sound type insulation?

What will you be covering the wall studs and ceiling joists with?

Dry wall, sheetrock, I assume?
How thick?
How many layers?
Type of glue used between layers?
Resilient channels installed on wall studs and ceiling joists?
Example of:
http://www.soundproofing.org/infopages/channel.htm

What ever you decide to do the electrician will need to know before he installs the outlet boxes.

Type of lighting in the rooms.


Jim


mrmb OP227 posts01-31-2018 9:47am

To Jea48, Jim:  As previously noted above, Al deferred to your choice of Romex MC (Metal Clad) as opposed to his original choice of Romex NM-B, by saying that he had “no reason to doubt that”…MC..”was a better choice”. Well NOW, if you are BOTH suggesting MC -- winner, winner, chicken diner, that’s what I will definitely use!


@mrmb,

I didn't recommend the use of MC cable over NM-B cable. I don't think Al, (almarg), did either.

As I said in one of my posts  I installed 10/2 with ground NM-B cable using plastic boxes for the two 120V 20 amp dedicated circuits for my 2 ch audio system.

I believe you said your 2ch and HT rooms will be located in the basement. I assume at least one of the 200 electrical panels will be installed in a mechanical room in the basement as well. I assume from that panel, the 100 amp sub panel will be fed from.
I assume the electrician will install the feeder wiring from the 200 amp panel, in the basement, to feed the sub panel through bored holes in the above engineered I floor joists, or trussed floored joists, above. The electrician, I assume, will also install the dedicated branch circuits wiring for the 2ch audio room and HT room from the sub panel. Either through the above floor joists or basement wall studs. Just make sure he keeps them from the ceiling can lights and load side branch circuit wiring of the can lights for reasons I stated in an above post.
@mrmb ,

You might want to contact your builder and ask him if he would call the electrical contractor and schedule a meeting where you can meet with the contractor, or his representative, so you can address your concerns. The fact that you said the electrical contractor’s main business is commercial and industrial is a good thing. That does not mean the electricians that will be wiring your new house will be Inside Wiremen and not Residential Wiremen. (Pay grade is a lot less for a residential wiremen.) It’s not unusual for a contractor to employ both inside wiremen and residential wiremen. Not to mention residential wiremen are trained how to wire houses fast.

Make sure at least one of the electrical contractor’s representatives you meet with is a State Licensed Master Electrician. He/she will have a better understanding of your concerns. Instructions will be given to the electricians who will be wiring your two audio/video rooms.

It is a lot cheaper to layout the job on paper beforehand than to make changes after the job starts. Change orders can be/are expensive.

If you have not watched the Cary Grant movie, " Mr. Blandings Builds His Dream House", I highly recommend you watch it.
https://en.wikipedia.org/wiki/Mr._Blandings_Builds_His_Dream_House

Jim


mrmb said:

I’m dealing with the Low Voltage estimates presently. Fortunately I’m much more attuned to the ramifications of what was needed to be spec’ed. with CAT6, Q/S-RG6 and fiber. Especially how CAT6 should be kept separate from the Romax, much like you explained about with the minimum 12" separation of the individual parallell branch circuits. I’m sure that sort of spacing isn’t something most electricians or low voltage technicans get overly concerned with, unless they’re required to....

Not all low voltage cable installers are created equal.
Did you ask the electrical contractor who he uses?

Make sure the Communication Company you hire will supply you with a copy of a certification test report for each data cable installed. Also the person testing the cabling, from the Patch Panel to wall jack, must be certified for the test equipment used.
Here is some reading info.
http://www.informit.com/articles/article.aspx?p=1403240&seqNum=3

Here, for an example, is a video showing an Ideal scanner cable tester.
Go to time mark 7:50 to see what’s involved in testing a 4 pair Lan data cable.
https://www.youtube.com/watch?v=wn-EsoD-FnQ

What manufacture of cable CAT6 cable will be used?

What manufacture of CAT6 Patch Panel/jacks and wall jacks?
I like Panduit. A little more pricey than the competition. Pair twist is maintained right up to the terminations. Same jack plugs into their Patch panel plate.
http://www1.panduit.com/en/products-and-services/products/safety-and-security/physical-network-secur...

Jim
Cabinet?

What all will be installed installed in the cabinet?

Patch panel
+
?
?


@mrmb,

Dedicated 120V branch Circuit.
A dedicated 120V branch circuit is a circuit with a dedicated, Hot conductor, neutral conductor, and safety equipment grounding conductor.

Usually the circuit is dedicated for a piece of equipment or appliance.
Example, a manufacture may require a dedicated 120V 20 amp circuit to fed his equipment.

Or the manufacture may have a cabinet with several pieces of equipment installed within the cabinet and he will require a 120V 20 amp dedicated circuit.

A true dedicated branch circuit, (an accepted electrical industry standard), does not share the same raceway, conduit, or cable assembly with any other branch circuit/s.

In your case you want to use dedicated branch circuits to power audio and video equipment in an audio room and HT room. The dedicated branch circuits are meant to supply power to audio and video equipment. General convenience 120V wall duplex receptacles outlets in the two rooms will be fed from a convenience outlet branch circuit.

You asked how many receptacles you can install on a 120V 15 or 20 amp branch circuit? Going from memory, NEC, in a residential dwelling unit you can install as many as you want. With that said, AHJ has the final say.


Jim