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LVX-6048 Ground Fault

if this thing has a bonded neutral then it’s worthless. It will never work with arc fault breakers. I was assured by MPP solar it was unbounded before I bought it. There isn’t a chassis ground either.

i have reached out to MPP solar with the above wiring description. Hoping they reply soon
I think I remember reading somewhere on here that the neutral/ground bond inside of some mpp inverters can be disconnected in the settings.
 
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if this thing has a bonded neutral then it’s worthless. It will never work with arc fault breakers. I was assured by MPP solar it was unbounded before I bought it. There isn’t a chassis ground either.

i have reached out to MPP solar with the above wiring description. Hoping they reply soon
So it seems like these inverters are designed to power a subpanel. The subpanel will not have a ground/neutral bond. So the inverter needs to have a ground neutral bond so there’s a ground /neutral bond at one place. If the subpanel needs grid power due to battery reaching low cutoff voltage (or for whatever reason) then grid power from the main panel (has a ground/neutral bond) comes into the inverter (pass through) and out of the inverters AC out. At this point the inverter isn’t producing power and the neutral ground bond inside the inverter should be automatically disconnected. This then allows for the main panel to be the only ground/neutral bond location for the power supply coming from the main panel through the inverter and to loads in the subpanel.

So yes these inverters are “worthless” if they don’t automatically disconnect/reconnect it’s ground/neutral bond. These inverters wouldn't be able to work with Ark fault breakers. And shouldn’t be used with regular breakers either. 2 neutral/ground bonds creates a ground loop.

Another thing I thought of, The power supply that typically comes from a main panel to a subpanel should be disconnected/not installed so that power from the grid can only go through the inverter to the subpanel.

If using AC charging it shouldn’t have anything to do with neutral/ground bond because the inverters AC input should be isolated from the AC output unless grid power is going through the inverter (pass through) to the subpanels loads.

I was just thinking out loud. Don’t know if any of that is correct
 
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Any update on this. I received mine Monday, and turned it on for the first time today. It seems to work fine in battery mode, but as soon as I added line power it started cycling, and beeping. The fault light was on but I couldn’t see a fault number. It was obviously very unhappy. I double checked all my AC connections (must say I am not a fan of the terminal block).

I went into the menu and changed the mode from SUB to SBU. when I brought utility back online it didn’t cause a crisis, but then again the battery was full. I suspect that if the battery disconnected I would be right back at it

Solar isn’t even connected yet. Not sure where to go from here
When your battery gets full the inverter is ready to power the subpanel, pass through is then stopped so this should automatically reconnect the inverters neutral/ground bond because the main panels neutral/ground bond would no longer be part of the circuit.
When battery is depleted and pass through from grid kicks in the neutral/ground bond inside the inverter should automatically disconnect
 
If this inverter does not automatically disconnect its neutral/ground bond then it can’t be used to pass through grid power to the subpanel. That would create 2 ground/neutral bond locations.
Maybe there’s something in settings not set correctly that is allowing some grid power to pass through while the inverter is supplying power to the subpanel. That would stop the ground/neutral bond from disconnecting.
 
OK first I have to give props to Ian at MPP solar in Utah. The man spent what had to be over an hour on the phone with me on and off across this afternoon. We isolated the issue as continuity between neutral and ground in the unit. He reiterated the fact that there is no intentional bond within the inverter, but we agree my issue is coming from a ground loop. He is going back to Taiwan this weekend for more info. there is evidently afirmware update to address the issue. There is a voltage leak inside the unit somewhere. More to come

right now I have a properly wired sub panel where neutral and ground feedback to the main where it is bonded. What we’ve done is drop all ground connections at the inverter itself. This is simply a stopgap. I am continuing to test some small circuits from the sub panel in this configuration while he gets his information from Taiwan. I’m hopeful at this point that we will get a good resolution where I can reconnect the grounds. Worst case right now the unit itself is ungrounded but the rest of the system is properly grounded. It’s working in this configuration
 
OK first I have to give props to Ian at MPP solar in Utah. The man spent what had to be over an hour on the phone with me on and off across this afternoon. We isolated the issue as continuity between neutral and ground in the unit. He reiterated the fact that there is no intentional bond within the inverter, but we agree my issue is coming from a ground loop. He is going back to Taiwan this weekend for more info. there is evidently afirmware update to address the issue. There is a voltage leak inside the unit somewhere. More to come

right now I have a properly wired sub panel where neutral and ground feedback to the main where it is bonded. What we’ve done is drop all ground connections at the inverter itself. This is simply a stopgap. I am continuing to test some small circuits from the sub panel in this configuration while he gets his information from Taiwan. I’m hopeful at this point that we will get a good resolution where I can reconnect the grounds. Worst case right now the unit itself is ungrounded but the rest of the system is properly grounded. It’s working in this configuration
Do you always have the sub panel properly wired from the main panel. Or did you do that after the problem occurred? If you had the subpanel wired like that while the fault was happening, Wouldn’t that cause an issue having the main panels input into the inverter and the inverters output in a loop. Basically like whatever the inverter draws into the AC input is being supplied out of the inverters output and back to the main panel..
Shouldn’t the power from the main panel to the subpanel only have one path only through the inverter. So the inverter wouldn’t be trying to send power out of its output into the subpanel and then into the main panel trying to supply the power coming into its input.
If the subpanel needs grid power then it should only get that grid power through the inverters pass through capability. Meaning the subpanel should not be able to get power from any other cable directly connected to the subpanel.
 
Do you always have the sub panel properly wired from the main panel. Or did you do that after the problem occurred? If you had the subpanel wired like that while the fault was happening, Wouldn’t that cause an issue having the main panels input into the inverter and the inverters output in a loop. Basically like whatever the inverter draws into the AC input is being supplied out of the inverters output and back to the main panel..
Shouldn’t the power from the main panel to the subpanel only have one path only through the inverter. So the inverter wouldn’t be trying to send power out of its output into the subpanel and then into the main panel trying to supply the power coming into its input.
If the subpanel needs grid power then it should only get that grid power through the inverters pass through capability. Meaning the subpanel should not be able to get power from any other cable directly connected to the subpanel.
To answer your question, no. i first tried wiring all 4 wires to the inverter, and then back to the sub as described above. The thought was the neutral and ground would pass thru the unit to the sub. when that didn’t work I tried adding the neutral and ground connections between the main and sub panels but that made things worse. There is not hot lead from the main to the sub, so nothing in the sub forms a circuit for the center tap on the utility transformer so no current flows on that neutral or ground. At least thats how I understand it
 
To answer your question, no. i first tried wiring all 4 wires to the inverter, and then back to the sub as described above. The thought was the neutral and ground would pass thru the unit to the sub. when that didn’t work I tried adding the neutral and ground connections between the main and sub panels but that made things worse. There is not hot lead from the main to the sub, so nothing in the sub forms a circuit for the center tap on the utility transformer so no current flows on that neutral or ground. At least thats how I understand it
So if the inverter does not have an internal ground/neutral bond and your subpanel doesn’t have a ground/neutral bond and the main panel neutral does not pass thru the inverter to the subpanel then your problem is that there isn’t a ground/neutral bond. When the inverters internal automatic transfer switch makes the inverter go into pass through mode I would then assume that the neutral/ground bond from the main panel would be used.
To fix not having a ground neutral bond I’ve read of people using a relay to connect ground/neutral at one point so that a ground/neutral bond is achieved when needed.
 
Stupid idea. You have a panel for utility and one for protected load. After that L and N can not connect from this 2 panel.
Is it possible that these N cables are bonded/connected somewhere in the house? Like a staircase with a double switch (1 switch on both level, L comes from one and the N comes from the other)
 
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Stupid idea. You have a panel for utility and one for protected load. After that L and N can not connect from this 2 panel.
Is it possible that these N cables are bonded/connected somewhere in the house? Like a staircase with a double switch (1 switch on both level, L comes from one and the N comes from the other)
ground loop imo doesn’t seem like eabryds problem. I think it’s that there isn’t a ground/neutral bond at all after the inverters AC output. Someone said earlier in this post that the inverters AC input neutral does not have continuity with the inverters AC output neutral. So could the severed neutral that is no longer providing a path to the ground bond be the reason for the fault. That severed neutral basically makes the neutral/ground bond in the main panel non existent
 
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A

ground loop imo doesn’t seem like eabryds problem. I think it’s that there isn’t a ground/neutral bond at all after the inverters AC output. Someone said earlier in this post that the inverters AC input neutral does not have continuity with the inverters AC output neutral. So could the severed neutral that is no longer providing a path to the ground bond be the reason for the fault. That severed neutral basically makes the neutral/ground bond in the main panel non existent

Can be.
I would love to see a wiring diagram. I really do not get what RCD trips, where it is (inverter AC in, AC out, ...) and so.
 
The pictorial wiring diagram from their website does not show the same wiring as the manual I downloaded from Watts247. The terminal blocks in the manual and on my unit have G, L1, L2 and N connections for both input AC and output AC. The ground connections have continuity and also the output neutral has continuity to the ground (they are bonded internally) There is no continuity between the input and output neutrals with power off at least, but the pictorial diagram shows continuity. We could really use an actual wiring diagram showing the autotransformer connections including how bonding is achieved. I have not installed my unit yet...
Your saying the ground and neutral are bonded internally. Eabryd says mpp fella from Utah said that neutral and ground is not bonded internally. Hard to diagnose this issue till we know for sure
 
Your saying the ground and neutral are bonded internally. Eabryd says mpp fella from Utah said that neutral and ground is not bonded internally. Hard to diagnose this issue till we know for sure

MPP bonds outgoing G to N when going into off-grid mode. Not before.
 
So if the inverter does not have an internal ground/neutral bond and your subpanel doesn’t have a ground/neutral bond and the main panel neutral does not pass thru the inverter to the subpanel then your problem is that there isn’t a ground/neutral bond. When the inverters internal automatic transfer switch makes the inverter go into pass through mode I would then assume that the neutral/ground bond from the main panel would be used.
To fix not having a ground neutral bond I’ve read of people using a relay to connect ground/neutral at one point so that a ground/neutral bond is achieved when needed.
Sorry I must not have been clear. Here are the connections
From main (bonded and grounded panel)
L1 to LVX L1 in
L2 to LVX L2 in
N to LVX N and to Subpanel N (unbounded, ungrounded)
G (bonded with N to subpanel G (unbonded, ungrounded)
These last two bond the subpanel N and G through the main panel

LVX out L1 to sub panel main breaker L1
LVX out L2 to sub panel main breaker L2
LVX out N to subpanel N
 
Sorry I must not have been clear. Here are the connections
From main (bonded and grounded panel)
L1 to LVX L1 in
L2 to LVX L2 in
N to LVX N and to Subpanel N (unbounded, ungrounded)
G (bonded with N to subpanel G (unbonded, ungrounded)
These last two bond the subpanel N and G through the main panel

LVX out L1 to sub panel main breaker L1
LVX out L2 to sub panel main breaker L2
LVX out N to subpanel N

So main AC in, N to G bond then separated ?
Subpanel you mean the protected load panel? There goes the N that goes into the inverter AC in too?
Not only the inverter AC out N goes to that subpanel ?
 
You were
Sorry I must not have been clear. Here are the connections
From main (bonded and grounded panel)
L1 to LVX L1 in
L2 to LVX L2 in
N to LVX N and to Subpanel N (unbounded, ungrounded)
G (bonded with N to subpanel G (unbonded, ungrounded)
These last two bond the subpanel N and G through the main panel

LVX out L1 to sub panel main breaker L1
LVX out L2 to sub panel main breaker L2
LVX out N to subpanel N
You were clear. Someone else said that the inverters AC input neutral does not have continuity to the inverters AC output neutral. That would make the ground bonded neutral in the main panel irrelevant for the circuit
 
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MPP bonds outgoing G to N when going into off-grid mode. Not before.
That is also how I thought this mpp inverters would handle the ground/neutral bonding.
Are you saying that there’s an internal switch that disconnects the inverters ground/neutral bond when the inverter passes grid AC power (from the main panel) to the subpanel?
 
if this thing has a bonded neutral then it’s worthless. It will never work with arc fault breakers. I was assured by MPP solar it was unbounded before I bought it. There isn’t a chassis ground either.

i have reached out to MPP solar with the above wiring description. Hoping they reply soon
They told me it's bonded when in battery mode
 
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