Bonding and Grounding Solar Components

[FilterGuy]

This 'conversation' is exactly why I say the word 'ground' is so overused, misused and misunderstood.

At the risk of sounding like a broken record, I will repeat: The System of Equipment Grounding Conductors, Grounding Electrodes and Neutral-Ground bonding serves two distinctly separate purposes.

Edited for clarity of meaning
1) It provides a low impedance path to ensure breakers/fuses pop in the event of a ground fault. This has nothing to do with a 'zero voltage' reference and the grounding electrodes tieing the system to earth ground are not needed for this purpose. It is simply ensuring that if there is a short between the hot wire and any of the metal bonded together with the equipment grounding conductor, there will be enough current to pop the breaker or blow the fuse.

2) It 'anchors' circuit voltage to earth potential so it does not float to some arbitrarily high value. This is done by tying the EGC system that is also connected to the neutral of the power system to earth ground using the grounding electrodes. The only relation to poping fuses or tripping breakers that tying to earth ground has is that it uses the same EGC system and N-G bonds that the Ground fault protection uses.

Both purposes are important. If I had to pick a 'primary' purpose I would say it is the ground fault protection because systems can be built without earth grounding.

 

[DerpsyDoodler]

Wrong
I guess that doodles made a second account.

Wrong. I have one account and one account only. Perhaps you may be the one mistaken? Or do you presume yourself perfect?

 

[Zwy]

It should be in NEC as earthing and grounding, the terms get interchanged often and why the confusion exists. I do it at times, guess over the years one gets used to using in interchangeably and it does cause confusion. Possibly the reason why is a ground (earthing) electrode or other earthing item such as a water pipe is tied to the grounding system and the N-G bond.

Take for instance this post: https://diysolarforum.com/threads/bonding-and-grounding-solar-components.37895/post-480228

Instead of using the word "grounding" I should have used earthing. I will say that I never recall using the word earthing when it comes to ground fault protection, so there is that.

 

[DerpsyDoodler]

This 'conversation' is exactly why I say The word 'ground' is so overused, misused and misunderstood.

At the risk of sounding like a broken record, I will repeat: The System of Equipment Grounding Conductors, Grounding Electrodes and Neutral-Ground bonding serves two distinctly separate purposes.

1) It provides a low impedance path to ensure breakers/fuses pop in the event of a ground fault. This objective can be met without tieing the system to earth ground and has nothing to do with a 'zero voltage' reference. It is simply ensuring that if there is a short between the hot wire and any of the metal bonded together with the equipment grounding conductor, there will be enough current to pop the breaker or blow the fuse.

2) It 'anchors' circuit voltage to earth potential so it does not float to some arbitrarily high value. This is done by tying the EGC system that is also connected to the neutral of the power system to earth ground. The only relation to poping fuses or tripping breakers that tying to earth ground has is that it uses the same EGC system and N-G bonds that the Ground fault protection uses.

Both purposes are important. If I had to pick a 'primary' purpose I would say it is the ground fault protection because systems can be built without earth grounding.

No, this conversation is because egotistical folks, rather than admitting what they know accurate, would rather try to confuse the matter with arbitrary red-herring. This thread needs a "Beware of trolls" sign posted.

 

[FilterGuy]

This will be my last post on this thread.

Please stay civil with each other. Disagreement is a good starting point for helping people learn, but if I believe someone is wrong, attacking them personally does not convince them to rethink their position. Instead, it pretty much eliminates the possibility of helping each other out. If I can't convince someone of my belief and they can't convince me of theirs.... the best thing is to agree to disagree and move on.

For the most part, this forum has remained civil and has been a great place to both learn and teach and I would like to see it stay that way. Seeing the growing vitriol in this thread is very disappointing to me.

 

[DerpsyDoodler]

This will be my last post on this thread.

Please stay civil with each other. Disagreement is a good starting point for helping people learn, but if I believe someone is wrong, attacking them personally does not convince them to rethink their position. Instead, it pretty much eliminates the possibility of helping each other out. If I can't convince someone of my belief and they can't convince me of theirs.... the best thing is to agree to disagree and move on.

For the most part, this forum has remained civil and has been a great place to both learn and teach and I would like to see it stay that way. Seeing the growing vitriol in this thread is very disappointing to me.

I agree. It almost seems like there are members who think they have some sort of territorial claim. Maybe that needs to be addressed.

 

[Will Prowse]

I'm getting tired of the members that make posts that have zero useful information in them. Not sure how to fix this but I'll consider deleting them if you guys report them. One rule I made is if someone is a nuisance to multiple members, we can vote on a ban. Let me know if you have any other suggestions on how to deal with it. I am tired of it too.

 

[Supervstech]

Sorry
But this would attract lightning, not avoid it.

Please do not make uneducated statements about electricity on this forum. Do research, don’t make anecdotal statements.
Thank you.

How to protect your solar power system from lightning

Lightning is a common cause of failures in photovoltaic (PV) and wind-electric systems. A damaging surge can occur from lightning that strikes a long distance

www.solarinsure.com

Panel grounding and panel ground rods attached to a solar panel frame is for lightning and emf energy from nearby lightning, wind static propagation etc, dissipation.

Ground rods do not attract lightning. This is a fallacy propagated by those who have little grasp of the concept.

 

[LywWyr]

Airfield lighting and navigational towers are prone to lightning strikes. These items are grounded using a system know as "equipotential counterpoise" . This method uses a single #6 bare soft drawn copper wire direct buried 12" above the conduit containing containing any conductors. It is bonded to the towers and a ground rod every 500ft. This is for lightning protection only and provides no "reference" for breakers to trip. It is never bonded to any panels , gutters ,conduit etc "System grounds" and "lightning protection" are two different things.

 

[Supervstech]

Look…

GFCI protects humans from being shocked from live current to ground, ONLY if the ground is a fault return path for the electrical system.

It is true a GFCI installed in a home wiring that has no grounding conductor in the circuit will still protect from a shock to ground…

But if the ground is not bonded to the neutral, thereby an isolated system, from earth ground bond… there is no shock energy loss, and no GFCI will trip.

In a mobile system, if the inverter is not bonded to chassis, the chassis is not a fault path… it is a very dangerous situation but it is not a ground fault path. It is dangerous due to many factors…

Having a ground mount array bonded to an isolated ground rod at the array as long as it is not connected to the home grounding system doesn’t create a lightning attraction system. Sure, if lightning does strike the array, there will be issues, lightning is incredibly powerful… but the grounding system doesn’t attract lightning… it dissipates it.

 

[timselectric]

This 'conversation' is exactly why I say the word 'ground' is so overused, misused and misunderstood.

At the risk of sounding like a broken record, I will repeat: The System of Equipment Grounding Conductors, Grounding Electrodes and Neutral-Ground bonding serves two distinctly separate purposes.

Edited for clarity of meaning
1) It provides a low impedance path to ensure breakers/fuses pop in the event of a ground fault. This has nothing to do with a 'zero voltage' reference and the grounding electrodes tieing the system to earth ground are not needed for this purpose. It is simply ensuring that if there is a short between the hot wire and any of the metal bonded together with the equipment grounding conductor, there will be enough current to pop the breaker or blow the fuse.

2) It 'anchors' circuit voltage to earth potential so it does not float to some arbitrarily high value. This is done by tying the EGC system that is also connected to the neutral of the power system to earth ground using the grounding electrodes. The only relation to poping fuses or tripping breakers that tying to earth ground has is that it uses the same EGC system and N-G bonds that the Ground fault protection uses.

Both purposes are important. If I had to pick a 'primary' purpose I would say it is the ground fault protection because systems can be built without earth grounding.

Thank you

 

[fisherus]

OMG!
I had no idea how difficult it would be to get, what I thought was a simple straight forward question, answered in this forum. Several of you have been good in helping me but, now my questions have become five pages of confusing argumentation. If you view this through the mind of someone who is making a large DIY install, for the first time, and you step back and read the content of what has been written, I'm sure you would be like I am. More confused now than when I posed my questions.

 

[timselectric]

OMG!
I had no idea how difficult it would be to get, what I thought was a simple straight forward question, answered in this forum. Several of you have been good in helping me but, now my questions have become five pages of confusing argumentation. If you view this through the mind of someone who is making a large DIY install, for the first time, and you step back and read the content of what has been written, I'm sure you would be like I am. More confused now than when I posed my questions.

I apologize for all of the confusion.
It definitely wasn't my intention.
This is why I decided to step away.
The discussion was becoming less helpful.

 

[DerpsyDoodler]

OMG!
I had no idea how difficult it would be to get, what I thought was a simple straight forward question, answered in this forum. Several of you have been good in helping me but, now my questions have become five pages of confusing argumentation. If you view this through the mind of someone who is making a large DIY install, for the first time, and you step back and read the content of what has been written, I'm sure you would be like I am. More confused now than when I posed my questions.

Can you post a diagram of your system? This will enable the folks here to better help you. Draw it on a napkin if you have to. include the components and how you think it should be wired. this will get you the help you need.

 

[Zil]

This is the problem with the industry. A lot of people truly believe that it's the right thing to do.
But, it's not.

I give way, brother. You obviously know more than all the industrial engineering firms I have worked alongside.

 

[Zil]

Last post here. Can any of you smarter than me explain how an off grid, NON_grid, system finds the earth to be a zero voltage reference?
In a non-grid system the ac circuit zero voltage reference is to the inverter case.

GFCI doesn't rely on any earth ground, green, bare, wire connections. It disconnects when the current going to and returning from devices, that is the neutral and hot, is approximately 5 milliamperes difference. It trips in less than 1/40 th of a second.

 

[DerpsyDoodler]

Last post here. Can any of you smarter than me explain how an off grid, NON_grid, system finds the earth to be a zero voltage reference?
In a non-grid system the ac circuit zero voltage reference is to the inverter case.

GFCI doesn't rely on any earth ground, green, bare, wire connections. It disconnects when the current going to and returning from devices, that is the neutral and hot, is approximately 5 milliamperes difference. It trips in less than 1/40 th of a second.

The purpose of a ground is something MASSIVE that can absorb and dissipate a massive amount of charge; thus capable of keeping any would-be zero-volt reference reliably at zero volts.

Does that help clarify?

 

[DerpsyDoodler]

If the GFCI's zero volt reference becomes something other than zero volts, current may not flow and therefore may not "trip" in the event of a fault. Not to mention the unsafe nature of charge existing on bare copper wire or chassis.

 

[LywWyr]

Fisherus.
You stated that you have provided lightning protection for the array .
I would run a #6 ground wire from the array , bond it to the combiner box then bring it into your main panel and bond it to your main panel and all the other system grounds.

 

[Supervstech]

Last post here. Can any of you smarter than me explain how an off grid, NON_grid, system finds the earth to be a zero voltage reference?
In a non-grid system the ac circuit zero voltage reference is to the inverter case.

GFCI doesn't rely on any earth ground, green, bare, wire connections. It disconnects when the current going to and returning from devices, that is the neutral and hot, is approximately 5 milliamperes difference. It trips in less than 1/40 th of a second.

Earth is a emf dissipation point, if the earth is in the path. Static, and lightning voltage potentials balance there.

GFCI difference is possible, only due to earth bonding with neutral. Without it, a GFCI that is searching for a leak to trip has no path to leak to.

Bonding is needed to prevent emf voltage potentials from building dangerously… that bond, raises the chance to get electrocuted by fault current traveling to grounded path through a body. The GFCI trips in this event.