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0 pointslazide4y ago0 comments

Keep in mind, while yes this is a huge code issue mixing low voltage and high voltage - ‘it depends’ in a lot of jurisdictions on other elements.

Following is for other folks running across this, in case it helps them.

At least in California, I’m pretty sure it’s code compliant to use rated non-metallic conduit for outside high voltage runs for instance. That conduit is made of PVC. It’s the grey plastic electrical conduit at every hardware store (if branded as UV resistant/outdoor rated).

Normal PVC pipe (for water) falls apart at too low a temperature and becomes super brittle when exposed to Sunlight surprisingly quickly.

It’s a much better idea to use EMT or even ‘hard’ conduit depending on how it’s exposed, but it’s not required. EMF protection is nice, but I haven’t seen a such a requirement for power feeds in residential anyway. If using 3 phase and some industrial equipment I imagine you’d be a jerk to not do so, but most residential neighborhoods here have overhead unshielded lines anyway.

Running to a separate detached building has a bunch of rules around grounding (for which you’ll find multiple mutually exclusive and conflicting codes across the county). Many areas don’t have lightning suppression rules though.

Depending on exactly how the building is constructed (technically ‘mobile’ vs ‘fixed) also changes codes a lot. Running the equivalent of an extension cord to a ‘mobile’ structure (which can be functionally fixed) is perfectly fine as long as it’s GFCI protected for instance. Not that he did that.

Ideally it would be a separate sub panel, grounded and protected as such, with proper rated conduit, etc.

But the bar is a lot lower than what you’re saying if someone follows some basic guidelines. And can be done safely.

But yeah, Article Author - you’re going to get someone killed. Jesus.

0 comments

hinkley4y ago

Ah yes, I know about the grey PVC but spaced on it. Typically this is for external runs bolted to the side of a building though. Or at least, that’s almost all I ever see it used for. Can you use it for open air horizontal runs? Say between two buildings?

Data you want shielded, for the reasons I stated. Stringing Ethernet between buildings often ends in tears.

jefftk4y ago

I ran outdoor-rated cat6 in metal conduit between my house and shed, about 6 feet, and it has worked very well. What do you see as the problem?

lazideOP4y ago

The issue is not running cat6 in a conduit (per se).

Original poster was running cat6 in the same conduit as high voltage residential Wiring.

That’s scary. The wires in cat6 can carry a surprising amount of current at 120v and wires get chafed or damaged sometimes.

It can be thermal cycling from load, or weather, or a gorilla yanked on them too hard during installation, or whatever.

That can result in 120v or 240v mains voltage at BIGAMPS (most HACR type breakers and residential panels can sustain 10k Amps for a tiny bit) until the wire vaporizes. That’s routine during things like AC compressor startup.

That can make that random ‘should be harmless’ RJ45 plug an immediate danger to anyone nearby. And since the wire won’t vaporize until there is a sufficiently low impedance path to ground, it can stay dangerous for awhile.

Also, different buildings somewhat often have different ground potentials, so running something low voltage and sensitive to voltage spikes and net current imbalance between buildings like Ethernet tends to not go well sometimes. It’s really hard to tell this is happening too, so it sucks to debug.

6 ft away? Probably not a problem if both buildings are grounded decently. Metal conduit helps with that as it acts as a supplemental ground path to reduce any potential differences.

Hundreds of feet? Can be a problem if you do it much.

1 more reply

hattmall4y ago

The cat 6 is fine, it's the power cable that's an issue. Realistically in this scenario it's fine too, it should be branched off of a GFCI. The only issue with the network cable is that it picks up static from lightning and blows some equipment, you can put Ethernet breakers on both ends though.

zrail4y ago

Not the OP but my understanding is that you're probably fine if that metal conduit is grounded. If you're stringing ethernet around outside you want properly grounded surge suppressors on both ends.

ethbr04y ago

UF-B. For a minute Lowes had their 100' mispriced by -$100 online. $80 wasn't bad for 100' of 10/3.

PaulDavisThe1st4y ago

> It’s a much better idea to use EMT

You cannot bury EMT underground.

One of the nice things about actual metal conduit, depending on the nature of the soil where you live, is that it only needs to be buried 7" down to meet NEC rules. PVC conduit requires significantly more depth.

lazideOP4y ago

Yeah we had a couple of comments going back and forth with conflicting scenarios. The one I was responding too was stating exposed above ground conduit, where EMT is often better than PVC due to sun exposure. Ridged is of course even better from a durability perspective, but a real hassle to deal with.

Burying EMT in soil or concrete is generally a bad idea and quickly leads to some serious tears - sometimes in a year or two with the right soil or if the concrete is exposed to harsh conditions).

Most codes technically allow it though, sometimes with ‘supplementary corrosion protection’. NEC 358.10(b).

Some electricians use duct tape for the ‘protection’ which is terrible.

Proper pipe wrap is expensive and doing it on your own is a real hassle.

[https://www.electricallicenserenewal.com/Electrical-Continui...] random link with some pictures.

That is one of the areas where plastic really shines - I’ve had great luck with schedule 40 or 80 rated plastic conduit - always go up a step or two in size above what you think you’ll need unless you hate future you. Schedule 80 for anything exposed to impact or exiting/entering the ground or a building.

And if you’re burying something like conduit, it’s almost always better to bury 2 or 3 instead of 1.

sokoloff4y ago

6” to the top of the conduit for IMC and RMC.

18” to the top of PVC conduit (12” for 120V, GFCI protected, 20A max overcurrent protection). If you’re willing to put 2” of concrete over it, PVC drops to just 6”.

j / k navigate · click thread line to collapse

0 pointslazide4y ago0 comments

Keep in mind, while yes this is a huge code issue mixing low voltage and high voltage - ‘it depends’ in a lot of jurisdictions on other elements.

Following is for other folks running across this, in case it helps them.

Normal PVC pipe (for water) falls apart at too low a temperature and becomes super brittle when exposed to Sunlight surprisingly quickly.

Ideally it would be a separate sub panel, grounded and protected as such, with proper rated conduit, etc.

But the bar is a lot lower than what you’re saying if someone follows some basic guidelines. And can be done safely.

But yeah, Article Author - you’re going to get someone killed. Jesus.

0 comments

hinkley4y ago

Data you want shielded, for the reasons I stated. Stringing Ethernet between buildings often ends in tears.

jefftk4y ago

I ran outdoor-rated cat6 in metal conduit between my house and shed, about 6 feet, and it has worked very well. What do you see as the problem?

lazideOP4y ago

The issue is not running cat6 in a conduit (per se).

Original poster was running cat6 in the same conduit as high voltage residential Wiring.

That’s scary. The wires in cat6 can carry a surprising amount of current at 120v and wires get chafed or damaged sometimes.

It can be thermal cycling from load, or weather, or a gorilla yanked on them too hard during installation, or whatever.

6 ft away? Probably not a problem if both buildings are grounded decently. Metal conduit helps with that as it acts as a supplemental ground path to reduce any potential differences.

Hundreds of feet? Can be a problem if you do it much.

1 more reply

hattmall4y ago

zrail4y ago

Not the OP but my understanding is that you're probably fine if that metal conduit is grounded. If you're stringing ethernet around outside you want properly grounded surge suppressors on both ends.

ethbr04y ago

UF-B. For a minute Lowes had their 100' mispriced by -$100 online. $80 wasn't bad for 100' of 10/3.

PaulDavisThe1st4y ago

> It’s a much better idea to use EMT

You cannot bury EMT underground.

lazideOP4y ago

Burying EMT in soil or concrete is generally a bad idea and quickly leads to some serious tears - sometimes in a year or two with the right soil or if the concrete is exposed to harsh conditions).

Most codes technically allow it though, sometimes with ‘supplementary corrosion protection’. NEC 358.10(b).

Some electricians use duct tape for the ‘protection’ which is terrible.

Proper pipe wrap is expensive and doing it on your own is a real hassle.

[https://www.electricallicenserenewal.com/Electrical-Continui...] random link with some pictures.

And if you’re burying something like conduit, it’s almost always better to bury 2 or 3 instead of 1.

sokoloff4y ago

6” to the top of the conduit for IMC and RMC.

18” to the top of PVC conduit (12” for 120V, GFCI protected, 20A max overcurrent protection). If you’re willing to put 2” of concrete over it, PVC drops to just 6”.

j / k navigate · click thread line to collapse