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The last 20 years of Home Power Have Been Amazing

In the late 1990s I installed my first electric panels. Mostly for the sake of running a safe woodworking workshop but also to enable the multiple window units and my partner and my offices, plus the TV and stereo, of course.

At that time whole house surge protectors were available but not required. Being an IT guy in a storm prone area of course I went for it. Otherwise however breakers were rather similar to those from the original mid 1960s versions. I mean, I’m sure there were improvements in panel technology and how breakers were manufactured but for the home there were really only two aspects you needed to care about:

  • Current capacity
  • Poles (1 or 2)

And for the home owner that’s were things stood for almost 40 years. In the last 20 years though much has changed. Arc fault (AFCI or CAFCI) first required in 2002 for bedrooms. Now (since 2017) they are required practically everywhere in a home. Whole house SPDs (surge protectors) are required from 2020.

Most recently, the 2023 NEC greatly expanded the use of Ground Fault (GFCI) protection. GFCI’s which were limited to kitchen and bath outlets are now required for your washer and dryer, microwave, range, dishwasher and (in my case) garbage disposal. Take a look at any modern panel. You’ll see 4 different types of breakers:

  • Old fashioned
  • GFCI (white test button)
  • CAFCI (dark blue test button)
  • Combined GFCI + CAFCI (pale blue test button)

And outlets? Have you noticed weather resistant (WR, 2008) or tamper resistant (TR, 2008) requirements? In addition to GFCI requirements. Sheesh. It’s a marvel any electrician can keep them all straight, let alone a home owner.

Of all these improvements though the only one I'd suggest you rush out and get is the whole house surge suppressor unless your breaker panel is running 40 years old in which case a replacement may be a good idea soon.

erik_squires
jea48
4,486 posts
 

 

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.

.

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.

.

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.

.

erik_squires OP
16,295 posts
 

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.

erik_squires OP
16,295 posts
 

* 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.

wsrrsw's avatar
wsrrsw
1,068 posts
 

@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. 

erik_squires OP
16,295 posts
 

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.

You are welcome, @wsrrsw - The year I moved in we had lightning strike near the Internet providers little ground box taking out several cable modems. Fortunately for all my neighbors they don’t even own an Ethernet cable and were 100% Wifi so only the Internet provider’s equipment was damaged, but it was close. You’ll find many stories of lightning surges coming through and zapping several pieces of AV equipment at once. Often though it’s not even visible, or it "only" damaged the Ethernet ports... meaning the gear was useless and had to be replaced.

While the damage is rare, and minor it is also expensive when it occurs. Especially bad for IT workers and audiophiles who like to connect as much as possible via wired network connections.

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