Grounding / bonding Victron Quattro

[WorldwideDave]

Right now the Victron Quattro is connected only to a 48V battery, no A/C in and no generator in.

No ground wire from Quattro chassis to anything.

A/C out has ground, line 1 hot and neutral. They go into 70 A load center with hot going to one breaker, neutral going to bus bar, and ground I don’t know what to do with.

I have an extension cord connected to load center. Black hot line to breaker, white neutral to bus bar, and green for now connected to other green with wire nut from the ac1 output of the Victron.

Because the small load center is the only load center in the system, should the ground and neutral both be connected inside the load center? If yes, should I then connect the ground from the extension cord to the neutral bus bar? Or should I have a separate bus bar inside of the load center and keep them separate?

That’s a very least, Should I be connecting a ground to the 70 Amp Load Center so that the case is grounded? I wish there was an idiot guide to the bonding / grounding stuff.

 

[WorldwideDave]

Related to this… I was going to run an extension cord from an outlet into the Victron Quattro AC in port. I have tested the outlet and it is wired correctly with ground, neutral, and hot. Inside of the Quattro, there is a AC line in, neutral line in, and the ground shares the same stud inside the Quattro.

Of course I know I need to limit the amperage in way down to something like 9 A just to be safe.

What does the decision to bring power to the unit from the grid change anything on how it is currently grounded / bonded or what the recommendation is on how to ground it?

I guess I don’t know if the AC input is connected to something that already has an earth ground and is bonded how that affects the AC output side or any of the recommendations to change.

Over the years, I have heard people say that some inverters will switch or handle the bonding and grounding stuff automatically, but I think it needs to be programmed on this device. 48/5000/70

Thank you for your time and for reading.

 

[timselectric]

If you have a grid input, that's providing your grounding system.
Don't do anything else. Your grounds in the loads panel, should be on a separate ground bar. And the neutral should not be bonded.

If/when you disconnect from the grid neutral, you have to provide a grounding system for everything that's not connected to the grid neutral.
The inverter may do this for you (dynamic bonding). If not, then you will have to figure out a way to accomplish this.

If you have to do the bonding manually, make sure that you remove this bond, before you connect to the grid neutral, again.

 

[Madcodger]

The Quattro can establish the bond. That's how I run mine in our off-grid system in the studio/guest house. Works well. Do NOT use the bonding screw in the panel when you do this, of course, as the bond is already eatablished. Note that this relay can be turned off, so do make sure it's on if you go this route.

 

[stromy]

Whatever you do, verify electrical safety afterwards. In all operating modes (e.g. off-grid, on-grid).
For a complete verification you need an "installation tester" e.g. fluke 166x, 167x, etc.
If you dont have access to that, get an "outlet tester"/"socket tester".

 

[WorldwideDave]

Whatever you do, verify electrical safety afterwards. In all operating modes (e.g. off-grid, on-grid).
For a complete verification you need an "installation tester" e.g. fluke 166x, 167x, etc.
If you dont have access to that, get an "outlet tester"/"socket tester".

I have the outlet tester. Three diff kinds, two diff brands. Won’t a good meter with probes tell you this too? Your concern is reversal of main and neutral?

 

[timselectric]

The two concerns are,
1. You should always have a ground (bond).
2. You should never have more than one.

 

[NC_hydro]

The two concerns are,
1. You should always have a ground (bond).
2. You should never have more than one.

How would someone feed two 200amp panels side by side? Haven’t confirmed yet but assuming both panels have NG bond or would it be upstream somewhere? If feeding both panels from a Victron Quattro system not sure that would work with two NG bonds no longer separate if being fed from a new panel tied to the inverters.

 

[timselectric]

How would someone feed two 200amp panels side by side? Haven’t confirmed yet but assuming both panels have NG bond or would it be upstream somewhere? If feeding both panels from a Victron Quattro system not sure that would work with two NG bonds no longer separate if being fed from a new panel tied to the inverters.

That's a great question.
If it were mine, I would move to a single bond, at the location where the two split from the grid.
The bond is required to be at, or before the first means of disconnect.
It's just usually at the first means of disconnect, because that's usually the easiest place.

 

[ricardocello]

I've got a meter base with 400A service that I installed in 2001.

It has two 4/0 SER feeds from the utility meter, no more than 2-3 feet long each, which go through the wall into the garage.
One feed goes to the 200A Main Panel, which has the Neutral-Ground bond screw.
The other feed goes to a single 200A Service disconnect breaker right next to the Main Panel.
That then runs to the other side of the house for a sub-panel.
So there are two panels labeled "Service Disconnect", you are allowed up to 6.

Inspector and PoCo people said, "That's neat work", which I'll take as a compliment.

The only other place I could have put the Neutral-Ground bond was in the meter base.
But I was told the inspector was looking for the Green Screw, so that's why I did it that way.

 

[WorldwideDave]

If you have a grid input, that's providing your grounding system.
Don't do anything else. Your grounds in the loads panel, should be on a separate ground bar. And the neutral should not be bonded.

If/when you disconnect from the grid neutral, you have to provide a grounding system for everything that's not connected to the grid neutral.
The inverter may do this for you (dynamic bonding). If not, then you will have to figure out a way to accomplish this.

If you have to do the bonding manually, make sure that you remove this bond, before you connect to the grid neutral, again.

So if no input from grid in ac in 1 on Quattro, I need to see if inverter is bonding inside itself for me? What would I look for in manual? Quattro 48/5000/70 120v single phase not split

Otherwise connect to grid and use that existing bond in the grid mains panel? Thanks

 

[ricardocello]

So if no input from grid in ac in 1 on Quattro, I need to see if inverter is bonding inside itself for me? What would I look for in manual? Quattro 48/5000/70 120v single phase not split

Otherwise connect to grid and use that existing bond in the grid mains panel.

See if the Ground Relay setting is enabled in Victron Connect or VE Configure.
When enabled, the internal relay will bond Neutral to Ground only when there is no grid present (inverter running).

 

[WorldwideDave]

See if the Ground Relay setting is enabled in Victron Connect or VE Configure.
When enabled, the internal relay will bond Neutral to Ground only when there is no grid present.

Thanks. Looking now.

 

[WorldwideDave]

See if the Ground Relay setting is enabled in Victron Connect or VE Configure.
When enabled, the internal relay will bond Neutral to Ground only when there is no grid present (inverter running).

I could not find that in VRM web site for my inverter. I also tried the remote console app and the vrm app. Must require VE.Configure on site. Will check later.

 

[ricardocello]

I could not find that in VRM web site for my inverter. I also tried the remote console app and the vrm app. Must require VE.Configure on site. Will check later.

Vicrton Connect will work on a desktop computer and with a USB MK3.
Otherwise, yeah, VE Configure on windows.
VRM doesn't generally let you play with any of the inverter settings because it involves hardware and safety.

 

[WorldwideDave]

Whatever you do, verify electrical safety afterwards. In all operating modes (e.g. off-grid, on-grid).
For a complete verification you need an "installation tester" e.g. fluke 166x, 167x, etc.
If you dont have access to that, get an "outlet tester"/"socket tester".

Picked up an outlet tester. If it has a green light and says wired correctly, safe to assume that whatever neutral and ground and bond stuff is happening accurately?
If it is an off grid scenario with no AC input, should I be connecting the inverter to my solar racking or some other earth ground even if the tester reports that the ground and neutral and hot are wired correctly?

I have a hard time believing that people in the DIY community who have small cabins in the middle of nowhere are driving 12 foot copper rods 11 feet down into the Earth without some excavation equipment to help push the rod down or something. Not sure how people are solving this problem.

 

[timselectric]

8" , not 12'.
And as long as you don't hit rock, it's usually pretty easy.
I've probably installed over a thousand.

 

[WorldwideDave]

8" , not 12'.
And as long as you don't hit rock, it's usually pretty easy.
I've probably installed over a thousand.

Ok. Added grounding bar in 70a mains panel and connected. Even added sticker with torque specs. I do that right?

 

[WorldwideDave]

Whatever you do, verify electrical safety afterwards. In all operating modes (e.g. off-grid, on-grid).
For a complete verification you need an "installation tester" e.g. fluke 166x, 167x, etc.
If you dont have access to that, get an "outlet tester"/"socket tester".

Verified.

 

[cs1234]

@timselectric

I've got two panels on my house.. one outside main panel (with neutral ground bond) one sub panel in the attached garage (uses bond from main panel).

I'm planning on doing double conversion with my inverter and disconnecting the two incoming hots, and the neutral coming from the main panel to the sub panel.. I want it completely independent from the main panel except for the ground wire. I'm leaving the main panel alone for now, no inverter to it, utility only. Can I reuse the ground wire like this, running it through the subpanel to main panel to ground rod?

Is it ok for me to have my inverter do the neutral ground bond internally (it has a setting for it to do so when inverting) and connect its AC outs to the sub panel? Or is there some type of conflict from the main panel neutral ground bond since the ground wire from the sub panel runs to the main panel before hitting the ground rod.

 

[NC_hydro]

That's a great question.
If it were mine, I would move to a single bond, at the location where the two split from the grid.
The bond is required to be at, or before the first means of disconnect.
It's just usually at the first means of disconnect, because that's usually the easiest place.

That makes sense, then when the interlock is flipped and the main breaker is off a NG bond at the inverter combiner load center can function for the two 200amp load centers that are now disconnected from their NG bonds.

 

[timselectric]

Ok. Added grounding bar in 70a mains panel and connected. Even added sticker with torque specs. I do that right?

Yes

 

[timselectric]

@timselectric

I've got two panels on my house.. one outside main panel (with neutral ground bond) one sub panel in the attached garage (uses bond from main panel).

I'm planning on doing double conversion with my inverter and disconnecting the two incoming hots, and the neutral coming from the main panel to the sub panel.. I want it completely independent from the main panel except for the ground wire. I'm leaving the main panel alone for now, no inverter to it, utility only. Can I reuse the ground wire like this, running it through the subpanel to main panel to ground rod?

Is it ok for me to have my inverter do the neutral ground bond internally (it has a setting for it to do so when inverting) and connect its AC outs to the sub panel? Or is there some type of conflict from the main panel neutral ground bond since the ground wire from the sub panel runs to the main panel before hitting the ground rod.

With no neutral connection between the two systems, they are independently bonded. Yes, I would let the inverter do the bonding. This way, if you add grid back to it, it will automatically disengage the internal bond. (You won't have to remember to do it)

 

[timselectric]

That makes sense, then when the interlock is flipped and the main breaker is off a NG bond at the inverter combiner load center can function for the two 200amp load centers that are now disconnected from their NG bonds.

The same bond is used always.
A breaker interlock only switches the hots.
This is called a common neutral setup. (And is preferred when possible)

 

[cs1234]

With no neutral connection between the two systems, they are independently bonded. Yes, I would let the inverter do the bonding. This way, if you add grid back to it, it will automatically disengage the internal bond. (You won't have to remember to do it)

Thank you for your answer @timselectric ! I often wait for your sagely advice before proceeding.

I was thinking of adding a 3 pole manual throw transfer switch to toggle it back and forth if need be, switching both hots and neutral.. I assume the same thing would apply in that scenario.