This thread might help, but I get a little lost when reading it. Can anyone else make sense of this thread?
I have an issue with current flow on my ground wire. My main panel has the neutral bonded (Sub panel does not). The LV6548 inverters - AC Line IN is not bonded, AC Line OUT IS bonded internally. (Everything looks good here to me) What I have found... While running sub panel circuits without...
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That thread is relating back to the N-G bond we have discussed a few times. I have tried to find out how the LV6548 deals with the bonding but have not been able to. (it is criminal how the inverter manuals often don't discuss this critical aspect of the system)
I know I have doubted the N-G bond (or lack thereof) is part of the observed problem, but let's do some experiments to find out.
However, before we play with an N-G bond, I think we need to look at how the neutral is wired. How hard would it be to disconnect the grid wires from the automatic transfer switch as shown below?
This would do two things:
1) Ensure the natural in and neutral out of the inverters are not tied together.
2) Get rid of the potential ground loop.
(BTW: What is the make/model of the transfer switch)
After the grid is disconnected from the transfer switch. See if the shocking problem is still there (pun intended). If the problem is gone, report back..... otherwise go to the next step.
The next step is to create an NG bond when the RV is in inverter mode and NOT plugged into shore power and the xfer switch is not hooked to the grid lines. As a temporary test, hook a 10 gauge wire between the ground and neutral bus in the breaker box and see if the problem still exists. Regardless of whether the issue exists still or not, put a good size 120V load on the AC and then measure to see if there is any significant current on the ground wire between the breaker box and the inverters. (If there is a current, the inverters have an internal N-G ground. If there is no current or just milliamps, the inverters do not have an internal NG ground. My guess is there will be no current)
Note: The N-G jumper in the breaker box is for the test and is NOT a permanent solution.
Next Step
@Hedges is correct that the Battery circuit should be bonded to the chassis ground. (The NEC requires it for 48V nominal systems).
For the final step. Add a wire between Battery negative and chassis ground. Let us know what happens.
My most recent theory was the batteries are isolated from chassis, so voltage gets bounced around by inverter, and so do PV wires.
This comment is what brought me back to wondering about the NG bond. Without the bond, the whole system is floating relative to chassis ground and earth ground. Could that be causing an apparent AC on the PV wires?
Without knowing a lot more about the internals of the inverter, I don't know if anchoring the AC side relative to the chassis ground will also anchor the DC side, but I would say it is possible.