Grounding rods and straps video

[Urge38]

Hi Guys,

So, I am getting close to installing my solar panels, and as per normal, I was looking to protect my investment, one thing led to another from surge protection devices and then on to earth rods/straps for the PV array.

before I link this very interesting video for you guys to watch and make what you will.

let me tell you, I have been a metal detectorist for some 30 years here in the UK

what this chap speaks off as per the Re-bar degrading/leakage is absolutely true.

make what you will and enjoy the vid

 

[Urge38]

This chap also recommends letting the inverters float (no ground) now let me just get my head around that one !!!!

 

[AZ Solar Junkie]

Yeah I'm not convinced this guy actually knows what he's talking about. I do not believe that grounding your array frames increases the likelihood of it getting struck by lightning. It just gives a path for any charge built up on the panel frames to dissipate to ground. It has little to nothing to do with the DC circuit (unless you have a short to the frame in a defective panel).

 

[SilverbackMP]

His premise is flawed. Grounding panels is not for lightning or or to connect a DC circuit. It’s in case there is AC leakage back into PV lines. And the ground should lead back to the common system ground. So instead of taking a path though you and back through the ground in an effort to connect a circuit, the AC takes the path of least resistance (the copper wire back to common ground).

Lightning ground or protection is a different beast.

Actual electricians and EEs please tell me if I got something wrong.

I don’t disagree with his lighting rod diversion techniques.

 

[AZ Solar Junkie]

I wonder what Tim would say about this one. Especially when he talks about the common/neutral in the AC circuit not being possible without the ground (around 3:40). I mean I know that the utility bonds neutral and ground (from what I've been told) just like you bond neutral and ground in your main panel for the home, but that statement seems off-base to me. For example, the Victron autotransformer creates its own new neutral, and it doesn't use a ground connection to do it from my understanding. I feel like I understand this stuff pretty well, but I'm not an electrician. What do you think @timselectric / other electricians out there?

 

[Urge38]

But

As this guy (in video) Says

The pv aluminium frame is not connected in any way to either off the pv positive or negative

The pv frame can't come into contact with the pv cables (unless your sloppy in installation)

Therefore grounding the frame does nothing other than say to a lighting strike "hit me as I'll take you to earth"

 

[SilverbackMP]

But

As this guy (in video) Says

The pv aluminium frame is not connected in any way to either off the pv positive or negative

The pv frame can't come into contact with the pv cables (unless your sloppy in installation)

Therefore grounding the frame does nothing other than say to a lighting strike "hit me as I'll take you to earth"

That’s the theory. Use the search function.

 

[Urge38]

That’s the theory. Use the search function.

as a learning exercise, I've since been doing basic research on earthing buildings for lightning strikes, it seems they all favour attracting the lightning Strick via a high placed higher attracting copper element and channelling it well away from anything.

 

[SilverbackMP]

as a learning exercise, I've since been doing basic research on earthing buildings for lightning strikes, it seems they all favour attracting the lightning Strick via a high placed higher attracting copper element and channelling it well away from anything.

Again, grounding per the US NEC (or other codes) has shit all to do with lightning. Two different things.

 

[Urge38]

Again, grounding per the US NEC (or other codes) has shit all to do with lightning. Two different things.

I dont live in the US, I live in the UK

 

[SilverbackMP]

I dont live in the US, I live in the UK

“…or other codes.”

Why am I even responding?

 

[timselectric]

I wonder what Tim would say about this one. Especially when he talks about the common/neutral in the AC circuit not being possible without the ground (around 3:40). I mean I know that the utility bonds neutral and ground (from what I've been told) just like you bond neutral and ground in your main panel for the home, but that statement seems off-base to me. For example, the Victron autotransformer creates its own new neutral, and it doesn't use a ground connection to do it from my understanding. I feel like I understand this stuff pretty well, but I'm not an electrician. What do you think @timselectric / other electricians out there?

This video has been posted before.
They are idiots.

 

[JRH]

This video has been posted before.
They are idiots.

Damn , ,,,,don’t beat around the bush Tim… …..tell us how ya feel about this …

 

[mciholas]

Yeah I'm not convinced this guy actually knows what he's talking about.

He doesn't. His theories and advice are dangerous and ignorant.

AC doesn't need the ground. It isn't part of a "circuit". That's total nonsense. AC uses a single point grounded neutral just to establish a reference voltage to surrounding earth. DC also needs a local reference just like AC.

Not grounding solar panels won't stop lightning. They are just as inviting to lightning ungrounded as grounded. The PV leads have already biased the panels to local voltage levels, so the lightning is going to find the panels nearby. If they are NOT grounded, most of the energy will now flow through the PV leads into your inverter or through the house itself. If they are grounded, that will divert MOST of the energy to the ground. This is why tall structures have grounding rods, not to attract lightning, but to divert it when it happens.

Grounding PV arrays also protects against wiring faults. Say a 400 VDC PV lead is rubbing against a frame and eventually gets through the insulation. If the PV rails are ungrounded, they now are energized at 400 VDC and nobody knows until someday someone touches it and ZAP. If the PV frame is grounded, that will shunt the voltage and you will be aware something is wrong.

That's the basic function of grounding, to safely redirect faults to ground instead of through YOU. Grounds provide no circuit or power function at all.

Ground everything. It is the safe and correct thing to do.

Mike C.

 

[AZ Solar Junkie]

Thanks for the sanity check. You electricians do a great job educating us, but as a layman sometimes someone says something that makes you start doubting if you’re understanding correctly

 

[scrubjaysnest]

That video is a law suit in the making. Do We Cheat them and How's love that stuff.