Anyone been able to source a GFCI with higher ratings of ground fault current that will solve the issue of a multiplus tripping residential GFCI outlets here in the USA? I have heard tell of “commercial” GFCIs that may be suitable for this but can’t find any.
best not to use any GFI device on the input to a multiplus, only on the output.
That’s easy to say but more difficult to achieve when exterior outlets in the US are required to have GFCI protection. A short perusal of this site shows many people with this issue. Typically an RV owner has a Multiplus installed, goes home to plug in to their exterior outlet that they have always used for their RV and it trips. “Whats wrong, it always worked before”, they say. Now we tell them, “Sorry, hire an electrician to install an RV specific outlet on the outside of your house”. I am looking for a simpler and less expensive solution. Like I said in my original question, anyone know of a GFCI that will “tolerate” a Multiplus without tripping?
If the Multi is in an RV or boat that requires the supply to go through an RCBO (GFI) then you need to have an isolating transformer also. Just increasing the differential current required to trip the GFI will not solve the issue, and just removes the protection from the GFI. When the Multi transitions from inverting to charging - connecting AC in, there is a brief period where the multi presents the N-E ground bond to the incoming source. Hence most likely ANY GFI will trip, unless you get a utility rated 5A differential current device.
Thanks for a more technical understanding. It does seem like a pretty big hole in the functionality of a Multiplus that should have been fixed a long time ago. I see post about this issue going back YEARS. People have found work arounds but there seems to be no response from Victron. For now I am going to try a simple solution from a thread from a few years ago that some have used. An amazon surge protector for 9.99 and a 15 amp grounding plug with the ground removed. This, or something that seems unnecessarily complicated like the isolating transformer, is what we are driven to so we can plug into a standard North American electrical outlet. I will echo what others have said for years. Victron, do you have a solution? @guystewart
Do you have a direction you can point me for this “isolating transformer” you speak of?
Here are some options: Isolation Transformers | Victron Energy
We Americans tend to think the world revolves around us and that it’s unimaginable that a company might not prioritize us. While I like Victron and many of their product offerings, they do not prioritize North America at all and there are many products they don’t produce for us along with several products that have known deficiencies. The GFCI issue in the USA and Canada is just one of them. If at all practical, I recommend you install a 30A or 50A circuit in the garage or outside the house. Installing an isolation transformer is easier, but limiting.
Eventually Victron will have to update the architecture of their inverter/chargers, but I wouldn’t hold your breath waiting for it. 
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This switching of the grounding relay seems to be an issue that could be fixed by a firmware update. HOWEVER, there could also be a liability issue here: If there is an instant where the inverter, in the process of switching over to AC in, releases the PE-N ground link while there is a fault (L-PE) on the load circuit, then it is possible for a potentially lethal scenario to occur. The probability of such a fault occurring at the same time as switchover is vanishingly small: this type of fault would trip the output protection before the ground is released, or would trip either input or output protection (or both) after the transfer is complete.
Either way, from Victron’s point of view releasing the ground link AFTER the transfer of L and N to AC in provides complete protection - even if it causes a temporary input ground fault.
In all Mobile installations from an engineering point of view, an isolation barrier at the circuit input is a required level of protection. This isolation cannot be provided by the multiplus, as there is a through path. It CAN ONLY be provided by an isolated charger or an isolating transformer.
Hence any firmware change affecting the sequencing of the ground relay is unlikely to happen.
Also:
DO NOT DO THIS!!! Not having a ground at all to avoid this tripping fault is potentially lethal.
I recommend reading chapter 7 of wiring unlimited.
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