The last 20 years of Home Power Have Been Amazing

Two years ago, we spent $10k with a licensed electrical contractor to get our aging yet still safe and working electrical panel replaced. This included getting the Power Company to change out the feed from the pole mounted Transformer. 

I had already ran two dedicated 20A lines into my living room. A 10AWG stranded line for all the audio crap and 12AWG Romex (solid core) line for the TV and computer crap including the Streamer. No more lights dancing in the living when the Subs kicked in or or noise/hum issues. Old or new Service Panel.

No sonic improvement of course over the old box which should signs of "yellowing" on the bus bars.

Living in Phoenix, the box in mounted outdoors and they did include a whole home surge protector. Funny thing was. When the Inspector came and saw how I'd layed out the two dedicated lines throughout my garage on the floor. He had a good laugh. In his words. This look like crap but it's all legal. I'd installed a junction box insode the garage and fed the two 20 A lines into it and then via flexible Armoured Cable, ran H,N,GND wires inside the one conduit while the other was 12-2 Romex inside flex armoured conduit.

Yeah, I could have just bought a PS Audio P20 for that kinda money but this minimizes any future risk and now my service also has been upgraded to a 200A service.

Came in handy when we installed an electric 220VAC dryer. I had them put a breaker in for future use. I had to punch a new hole in the top of the box and run a bit of conduit out into the garage. 

I had already ran two dedicated 20A lines into my living room. A 10AWG stranded line for all the audio crap and 12AWG Romex (solid core) line for the TV and computer crap including the Streamer.

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I’d installed a junction box inside the garage and fed the two 20 A lines into it and then via flexible Armored Cable, ran H,N,GND wires inside the one conduit

I’m not a fan of stranded wire for feeding audio equipment. I would of used solid #10 wire.

How are the H,N,Grd pulled in the conduit? Just loosely, randomly? Best practices, (for feeding Audio/Video equipment), is to twist the Hot and Neutral conductors together the entire length of the conduit. Pull, install, the insulated EGC (Equipment Grounding Conductor) straight along side the twisted pair in the conduit. Good chance you would have a lower noise floor than you have now.

Actual Lab testing:

Scroll down to page 13.

AC Magnetic Field Strengths from Different Wiring Types

AC current flowing through a conductor will create an AC magnetic field along the entire length of
the wire, the magnitude of which will vary in proportion to the amount of current. This field may
inductively couple noise voltage to signal wires running parallel, which can result in hum and buzz.
The longer the run of these parallel wires, the greater the inductively coupled noise voltage will be

Also the loosely, randomly, installed H & N current carrying conductors will induce a voltage/noise onto the EGC.

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An Overview of Audio System Grounding & Interfacing

Read page 16. Pages 31 thru 36.

Note the chart on page 35. The worst case is H, N & EGC conductors pulled loosely, randomly, in a conduit. Best is the H & N twisted together with the EGC pulled straight along side the twisted pair.

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BTW, all the reading I've read about surge protection agrees with @jea48 .  Perhaps the most in depth explanations happen from the blogs at ZeroSurge or Brickwall.   As makers of series mode protectors (like Furman with SMP) they point out, correctly, that for shunt protection distance matters and that small amounts of resistance and / or inductance per foot can add up to significant drop in effectiveness.  The impedance per foot causes a voltage rise per foot that remains at the appliance terminals.

The distance/voltage rise arguments against shunt type protection mostly go away when we think of a panel mounted device though.  The panel is exactly the right place to put one.  However they will perform better with lightning type surges when mounted as close to the line / master breaker as possible and with the shortest, roundest possible leads which AFAIK is what the installation documents recommend even if they don't go into as much detail.

Every severe strike is different, and there are no guarantees so at best we are playing with probabilities.  Even if you do everything right with the whole house unit a point of use surge protector is still recommended.

* Correction:

For high rise time currents a short, straight wire is ideal, but if you can’t have that then avoiding sharp bends altogether is your next best alternative. That’s what I meant to say. In some photographs you can actually see evidence of a surge current jumping around a bent wire, evidence that the impedance was high enough to raise the voltage enough to jump.

@erik_squires Thx for your blog post about the EverStar MI-300 Ethernet Galvanic Isolator. If we do it for electricity makes sense to do it for ethernet too.