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solitude-rv avatar image
solitude-rv asked

Multiplus-II 2x120V tripping GFCI

I have Multiplus-II 2x120V that was just installed in a fifth wheel RV (together with Smart Lithium batteries, Lynx BMS, Cerbo GX and GX Touch 50). The Multiplus is connected behind an EMS and a Generator transfer switch.

I have it currently connected to 20 amp 120V single phase shore power US GFCI outlet. In Cerbo GX I limited the current to 10 amp just to be on the safe side.

The problem is the Multiplus trips the GFCI outlet. This has never happened before I installed the Multiplus-II in my RV.

To diagnose it I connected it to a different (non GFCI) outlet in which I wired a current meter on the ground line. I also turned off the main 2 pole 50Amp breaker on the RV breaker panel (that is connected to AC out 1 of the Multiplus).

When I turn on the power to the shore outlet with the current meter wired on the ground wire:

0) I turned the Multiplus off using the GX Touch interface

1) First my EMS has a delay of 144 seconds before turning on the power. During that time the current on the ground wire measured at the outlet described before is ~0.5 mA. So far so good.

2) After the 144 seconds delay the power to Multiplus turns on. The current on the ground wire is 1.5mA. So far so good.

3) If using GX Touch I switch Multiplus to Charger mode the current on the ground wire jumps above 10mA, which is way above the level that trips the GFCI (4-6mA).

Then to rule out a faulty cable connected to AC out 1 I disconnected a ground wire from the Multiplus AC out 1 and on the other end of that cable I disconnected a ground wire from the RV service panel, so there is no way that the cable connected there is introducing any current on the AC in ground wire. Still all the measurements were exactly the same.

For what is worth the current seems to decrease over time (when the charing current decreases), but even with completely full batteries it is ~5.5mA.


Also: the 120V cables are Romex 6 AWG, the ground is a single solid conductor so there is no risk of one of the strands not getting into slot.

I have also verified with a thermal camera that no wire connection to AC in/out is overheating.

Multiplus-II
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Mike Dorsett avatar image Mike Dorsett commented ·
4- 6 mA is VERY low for a ground fault trip. European tyrips are normally about 30mA (reduced from 40mA). 10mA of ground current does not seem to be excessive for an appliance. The usual source of ground current is the EMI filter, nessecary to meet the EMC regulations. Only way round this would be to use an isolating transformer
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solitude-rv avatar image solitude-rv Mike Dorsett commented ·
This device is made specifically for the US market (2x120V version). The US regulations are 4-6mA for GFCI. And for years, by law, every outdoor 15A/20A receptacle has to be GFCI.


IIRC the threshold for charger type devices in US is 3mA (0.5-1mA for regular ones). If this device is not meant to work with US GFCI outlets I think this should be clearly documented as it is a serious limitation.
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ludo avatar image ludo solitude-rv commented ·
Charger, as for smartphones etc. ?
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solitude-rv avatar image solitude-rv ludo commented ·
Charger as in RV charger/inverter.
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offgridcircuits avatar image offgridcircuits commented ·
I have the exact same issue, same inverter plugged into a 20A GFI in the USA. Once the inverter's transfer switch kicks in, the shore power GFI it is connected to, trips. I cannot figure out why.


Did you get yours resolved.
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ludo avatar image ludo commented ·

Is the ground relay in multi on or off ?

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solitude-rv avatar image solitude-rv ludo commented ·
Why would it matter if the multiplus is in charger mode?
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ludo avatar image ludo solitude-rv commented ·
I don't think the relay is switched dependant of op mode.
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solitude-rv avatar image solitude-rv ludo commented ·
If it wouldn't then in the pass through mode there would be two points of bonding ground and neutral. Per schematics this relay is closed only when inverting.
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klim8skeptic avatar image klim8skeptic ♦ solitude-rv commented ·

Per schematics this relay is closed only when inverting

Open when AC is present at input, and being passed through.

Closed when the backfeed relay is open.

(unless the "Ground Relay" behavior has been programmed differently.)

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solitude-rv avatar image solitude-rv klim8skeptic ♦ commented ·

I think I am missing something in what you are saying. Could you please provide some reference for this?


My reference - Multiplus-II 2x120 manual:

https://www.victronenergy.com/upload/documents/MultiPlus-II_12V-24V_3kVA_2x120V/MultiPlus-II___Quattro-II_120V-230V-en.pdf

At the end there are 3 power flow diagrams:

Power flow inverter - internal ground relay CLOSED

Power flow single phase - internal ground relay OPENED

Power flow split phase - internal ground relay OPENED


And in other parts of the manual:

"The MultiPlus-II is provided with a ground relay (relay H, see appendix B) that automatically connects the Neutral output to the chassis if no external AC supply is available. If an external AC supply is provided, the ground relay H will open before the input safety relay closes. This ensures the correct operation of an earth leakage circuit breaker that is connected to the output."


Having this relay closed when AC is present is definitely a very bad idea. My understanding of the setting is that the relay is open when not inverting and the setting only controls what happens when inverting.

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ludo avatar image ludo klim8skeptic ♦ commented ·
It will never hurt to check.
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robh avatar image robh commented ·
Also have the same issue, appears Canada has the same GFCI for outdoor plugs. Plugged into an indoor socket and works no problem.


Grateful for the work around as was pulling my hair out and needed charge in cold conditions.


Never the less agree a comment from Victron would be good that it is indeed being looked at.

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cdsolar avatar image cdsolar robh commented ·
I have the UL 3000/48 single leg version of the MP II. I am in the USA. I may be having this issue.


On a circuit where AC-in is connected, I have other devices.

Before the multiplus (MP) was added:

LED (vegetable grow light) + extension cable = no trip

After MP added to circuit:

LED + extension cable + MP = trip

LED + MP = no trip

Extension cord + MP = no trip

This first happened when I turned on the LED Grow light after adding the MP.

The extension cord was plugged into the circuit, but had no loads.

So perhaps all of the MP, LED Grow light, and the extension cord all have ground leaks, and the sum of them is greater than the trip current limit.

I am getting a new extension cord and will add it back in and test again....But for now, without the otherwise empty extension cord, I am not tripping GFCI.

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27 Answers
gklott avatar image
gklott answered ·

Response from PKYS.com trouble ticket:

“We see this from time to time but I have never once see it be the fault of the MultiPlus. You can test it out by taking the Multi completely out of the AC wiring system and testing it in isolation. If you can replicate the fault then you might have a warranty claim.

This kind of fault can be caused by any of the following:

  • Any connection between neutral and ground.
  • Any connection between the current carrying conductors on the input side of the multi and the output side.
  • If you have multiple shore power connections any connection between the two separate systems
  • If its a boat you may also get faults caused by salt deposits on connectors,
  • A water heater element is another source of ground faults.
  • See my article about it. How to deal with a boat that is tripping the dock Ground Fault circuit breaker

If you bought the unit from PKYS and want to do a warranty claim let us know after you have tested it outside your AC Wiring System.

Peter Kennedy

PKYS INC”

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Casey Pries avatar image
Casey Pries answered ·

I'm having the same problem with my MP II 2x120 and I've not even connected up the chassis ground yet (planning to). It typically seems to happen sometime after it charges the batteries up to 100%.


I've also only got it connected to 1 outlet at the moment. I'll be connecting it to my breaker panel before too much longer. So I'm fairly certain it's an internal issue with the inverter.

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moneyslinger avatar image moneyslinger commented ·
Yep, mine charged for over 6 hours, when batteries reached 100% it's tripped.
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bradgarrison avatar image
bradgarrison answered ·

FIXED!!!


Last year, I installed a Victron Multiplus II, Cerbo GX, and Smart Solar in our 2020 Grand Design 2800BH. While this setup worked flawlessly during boondocking, I encountered an issue when connected to shore power: the GFCI outlet would trip after about a minute. Initially, I suspected the problem was related to the Victron system, as the camper did not trip the GFCI before this installation.

I first verified the wiring multiple times, updated the firmware, and read through numerous posts from others who had experienced similar issues. A few weeks ago, I decided to test the setup further. I used an extension cord with the ground wire cut off and plugged the camper into the GFCI outlet. This prevented the GFCI from tripping, which suggested a grounding issue.

Next, I used a volt-ohm meter to check the resistance between the camper’s steel frame (where the Victron Multiplus was grounded) and the aluminum frame (where the WFCO distribution panel was grounded). I discovered resistance between these frames, indicating a grounding problem. It was a small amount of resistance but enough to trip the GFCI.

The issue stemmed from the change in grounding configuration after the Victron installation. Originally, the 50-amp input connected directly to the WFCO panel, which was connected to the aluminum frame. Also, all the camper circuits are grounded back to the WFCO panel. With the new setup, the input went directly to the Victron, which connected to the steel frame. This altered the camper’s grounding and introduced resistance between the steel and aluminum frames.

To resolve the issue, I installed a ground wire connecting the steel frame near the Victron to the aluminum frame near the WFCO panel. This adjustment eliminated the resistance, and the GFCI issue was resolved.

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ludo avatar image
ludo answered ·

Hi,


An RV with 50a circuit breakers is surely not designed for use on a 15-20a receptacle.


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solitude-rv avatar image solitude-rv commented ·

I respectfully disagree.

This is a little bit like sentence Ferrari is surely not meant to be driven on a residential road with 25mph speed limit.


Victron even supports limiting the max load and on purpose made this setting go down to values that make it usable with US 15A/20A outlets.

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ludo avatar image ludo solitude-rv commented ·
Yes, in Italy we even have outlets that are limited to 5a, but with 30ma GFCI. Generally the 10ma units are reserved for bathrooms.
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Kevin Windrem avatar image
Kevin Windrem answered ·

GFCIs will trip with a neutral to safety ground short even without any load currents. It doesn't take much voltage on the neutral to account for 10 mA.

I would disconnect the AC output (all 5 wires) from the Multi and test again.

I would also (with all power off) check resistance between ground and neutral at various points in the system.

If you find continuity between any of the neutrals and the chassis on the Multi with everything disconnected, it has an internal fault and should be replaced.


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solitude-rv avatar image solitude-rv commented ·
Thanks!


When I disconnected both ends of the ground wire from the ac out cable I also made sure that there is no way for any part of the cable to contact the ground.


Also since this is happening only when multiplus is in charging mode (not off) I don't think measuring resistance will help. This is also somehow proportional to charging current and none of this was happening for weeks before installing multiplus.

Can somebody from Victron confirm what current they expect on the ground wire? I don't think 0 is the answer.

I can definitely send this unit back, but how do I use the RV in the meantime? It took my Victron dealer 3 attempts to send me a unit that is not broken in transport. So if now I will not be able to use my RV for 3+ months then it's kind of nonsense, right? And honestly I have a feeling that next unit will be exactly the same - thus asking Victron what they expectation about ground leakage is.


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Trevor Bird avatar image Trevor Bird solitude-rv commented ·

@solitude_rv I can only make a comment from an Australian perspective but have done signifcant work on this subject. In Australia a typical RCB ( Residual Current Breaker) in a van park or marine dock is rated at 30mA. 30mA is the maximum current it should trip. The RCB can trip at 50% of the rated value and still be within manufacturers specification. That is 15mA. Typically in practice they usually trip at 20mA. As mentioned by another poster, the culprit can be the EMI filters on the input of various devices. That means the leakage current exists even if the device is switched off as the EMI filter appears at the power input to the device. This requirement is more evident in modern devices as more "switch mode" type power control is used. The current "leaked" through these EMI devices is not a fault but rather a function of the small capacitors used in the EMI filters. Each most basic simple filter cause about 0.35mA of leakage current. They accumulate and are capacitive in nature. In other words the current phase angle is 90 degrees to the voltage. If you have enough "gadgets" it is easy for capacitive leakage currents to accumulate. I am surprised your jurisdiction calls for tripping at 4-6mA on feeder circuits feeding full supply to complex installations like a RV. If that were the case in Australia, we would never get a boat to stop tripping. It would be a nightmare. We would typically see a steady state of up about 10mA without any concern at all.

The feeder circuit to an RV or a boat which has its own distribution board is quite different from an invividual final circuit protection. A low leakage current GFCI is fine for a final circuit to protect one appliance at one outlet but the feeder circuit to power an entire large boat or an entire large RV facility must surely take into account the accumulation of many small leakage current developed within the boat or RV.

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solitude-rv avatar image solitude-rv Trevor Bird commented ·

Thanks Trevor, I understand. The regulations we are talking about here apply to the whole United States. Since all 120V/240V breakers in the RV are off, my measurements were of essentially the Multiplus itself, so the cumulative effect you are describing doesn't really apply here.

Multiiplus, per its product page, is "the perfect one-box mobile solution for standard North American 50A 120/240VAC split-phase applications". IMHO not so perfect if it doesn't meet standards in the US and you cannot connect it to a GFCI, right (that is required outdoors for 15A/20A)? I have been to plenty of places where the only thing RVs have available is a 20A outdoor GFCI outlet (e.g. barns next to horse arenas).


Does anybody know how can I get Victron to express their opinion on this? Is my unit "working" in their opinion or should it be replaced?


I think it is not only my problem, I think RV community in the US will really be interested in this.

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Kevin Windrem avatar image Kevin Windrem solitude-rv commented ·
The breakers only disconnect the hot leg of the power connection. The neutral remains connected. You must disconnect the wiring to totally isolate your distribution panel.


For service you need to contact your dealer. Victron does not offer direct customer support.

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Thomas H. Clancy avatar image Thomas H. Clancy solitude-rv commented ·
Yes, it's explicitly made for 50a split phase use.


Not for 15/20a household wiring ?


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Kevin Windrem avatar image
Kevin Windrem answered ·

Before I completely rewired the AC electrical system in my travel trailer and before I added my Multi, plugging in the shore power cord would trip the GFCI. It could take several cycles of the GFCI reset to get it to hold. My assumption was the EMI filter in the converter inside the WFCO distribution panel.

My rewire eliminated the WFCO panel completely and even with the Multi Compact in place I haven't experienced GFCI trips although I should say that I now have a separate 30 amp circuit without a GFCI for the travel trailer.

There can be alternate ground paths especially to the converter inside typical RV power distribution panels due to the combined AC and DC power management. This is why I suggested removing neutral and hot legs in addition to the safety ground wire from the output of the Multi.

If there is a neutral-safety ground short somewhere in the system, the GFCI trip could easily be proportional to load current. So measuring resistance between safety ground and neutral may turn up the fault. But do so with the shore power disconnected because there IS a neutral-safety ground connection up stream of the receptacle you are plugging into.

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Jeremy Albrecht avatar image
Jeremy Albrecht answered ·

I’m a bit late on replying here, but I have the exact same issue with my MP2 120x2. It happens even if I disconnect all wires from the output, and with the MP2 set to Charger Only, and with nothing else plugged into the circuit.

This has happened since I installed the thing this summer.

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narcosis avatar image
narcosis answered ·

I'm also fighting this same problem. Even if I disconnect everything and use charger only it will still randomly trip the GFCI. I also have a MP2 120x2.

No issues when I'm using a generator or a regular circuit. Only happens with a GFCI. I have even set the current limit to 10A, but no luck.

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stvaughn avatar image
stvaughn answered ·

I have the same problem with my RV installation. Sure wish Victron would address this issue and come up with a solution.

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Jeremy Albrecht avatar image Jeremy Albrecht commented ·
A fix would be great, but even an acknowledgment would be appreciated.
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gklott avatar image
gklott answered ·

I too am experiencing the same issue with our MultiPlus-II 12/3000/120-50 2x120V PMP122305100. With 2020 NEC, §210.8(B)(4) requires GFCI (5 mA) on all outdoor outlets up to 250V and 50A. That’s what we have for RV 30A single pole GFCI, and the MP2 consistently trips the Eaton BRN130GF. Replaced breaker twice, and it triped all three breakers. GFCI trips with nothing connected to L1 and L2. It will go for several days and trip, or reset and it will trip in an hour. With nothing but main RV 30A breaker and wiring feeding MP2, ohm meter reads “open” between neutral and ground. This has been going on for 2 months since install. I have the latest firmware. Except for an actual fault, the MP2 should not trip this 30A feeder breaker. We have two other RVs with Sterling Pro Ultra Chargers and AIMS 3kW inverters, also on GFCI, and they do not trip the breakers. The Victron MP2 is the only unit causing this issue.

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Jeremy Albrecht avatar image
Jeremy Albrecht answered ·

Could we get a comment from Victron in here? Even if it’s blaming us for having our installs wrong, it would be better than silence.


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gklott avatar image
gklott answered ·

I submitted a trouble ticket on this issue to PKYS.

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richie-trent avatar image
richie-trent answered ·

Hello all, not sure if this pertains to anyone's specific setup here, but I was having the same issue and just solved it on my system. The Multiplus (12/3000/120-80) was tripping GFCI outlets when I would plug into shore power. Didn't matter if it was set to Charger Only or Inverter, as soon as it kicked on it would trip the shore GFCI.

In my system I'm using a Progressive Dynamics AC/DC distribution panel. This panel has a pre-wired 120vac outlet on it, where the neutral and ground are wired to their busbars, and the hot is left open for the addition of a breaker. I disconnected the neutral and ground from the busbars and it no longer trips the GFCI outlet.

I would love if someone could expound on why that would trip the GFCI, but at this point I'm just happy that it is fixed.

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moneyslinger avatar image moneyslinger commented ·
Wondering what RV make/model you have? Thx
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giz99 avatar image
giz99 answered ·

I had the same problem for a long time and I finally found a solution on my system.

I found this not on a Xantres Forum

When installing an inverter/charger, it is important that the AC output side of the inverter feeds its own hot and neutral buses. These buses need to be isolated from the input MAIN hot and neutral buses. All the loads that are fed by the inverter need to connect to these isolated hot and neutral buses.


I found that my shore power was connected to the neutral bus that everything else was connected to. I changed my wiring so that the shore power was going to the Multiplus only. After I did this no more blown GFCI


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mayhem1328 avatar image
mayhem1328 answered ·

Was this ever solved by the OP? I have the same issue and I've checked my N and grounds and they are not tied.

This happens only when plugged into a storage pedestal for charging purposes.


One thing that I did was shut all breakers off and then turn on the multiplus II.

Then turned on one breaker at a time and waited for a trip. Nothing... eventually got all breakers on and it didn't trip the same gfci pedestal.


After checking everything.. I noticed that when I first plugged in the multiplus II, it goes into Bulk charge mode. About a minute later it tries to switch into Absorption mode (click). That's when the pedestal gfci pops. When I did the breaker check above.. by the time I got to the second breaker, the multi had already switched into absorption mode... so all the breakers were eventually switched on.

There has to be something within the multiplus when it is switching charging modes that causes the pedestal gfci to pop.

Same as everyone else - this does not happen on a 50amp service or under genny power. Only on a 20amp storage plug (no matter which one I try).


I did see someone mention to use an extention cord without a ground nub, but I haven't done this.

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moneyslinger avatar image moneyslinger commented ·

Yep, I reset my 20amp garage GFCI (with RV batteries at about 70% capacity) and it charged fine for over 6 hours, then tripped. That's when I saw batteries reached 100%.

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houlster avatar image
houlster answered ·

This is happening to me as well on a dual MP II 2x120 (parallel) install. Tried plugging into a 30 gfci at a campground and as soon as the Multi connects power, the gfci trips.

I installed the multi's with a 3-way switch bypass and the Multi's output is through a circuit breaker. I can shut off the breaker & bypass the multi's to completely isolate them and power goes directly from my ATS to the RV power panel just like before adding the inverters. Doing this, the gfci circuit did not trip.

Finally, I sacrificed a spare 50a/30a dogbone by cutting off the ground pin of the 30a side and tried it with the Multis, and the gfci did not trip.

This is all telling me that something inside the MP II is leaking neutral to ground. Enough to trip the sensitive US gfci outlets.


Other thing of note regarding problematic OEM 12v converters: My MP are the 24v model. I keep the circuit breaker for the OEM converter in the panel shut off and have a victron 24/12v converter to keep the original 12v batteries charged.

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Jeremy Albrecht avatar image
Jeremy Albrecht answered ·

Unfortunately I think we’re out of luck until Victron decides to do a hardware fix. Since the device is designed around Euro specs allowing a max leakage of 30mA which is over the allowed leakage for a US GFCI of 6mA, there’s nothing we as end users can do.

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plrpilot avatar image
plrpilot answered ·

I'm adding myself to the list of users with this problem...

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mitchell avatar image
mitchell answered ·

I have at least 10 systems using this inverter that we have installed or sold that are experiencing this same issue. I did a bunch of testing and was able to determine that if you turn off the Aux relay (AC ouptut 2) that temporarily fixes the issue. This allows the GFCI to supply power until the MPII is in float, then it trips the breaker. Why when it's in float?

I was hoping to find a solution with this model but I'm losing faith. I think a hardware redesign fix is needed. The unfortunate thing is that this Multiplus is specifically designed for RVs and it's not GFCI compatible. Most other applications wouldn't care but RVs specifically need GFCI compatibility. I have been installing Victron inverters in RVs for 8 years and this is the first model that has this issue.

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derrick thomas avatar image
derrick thomas answered ·

Just curious if anyone has tried disabling the internal neutral/earth bonding relay and install an external bonding relay? I had a similar issue years ago with a magnum inverter and doing that eliminated it.

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mitchell avatar image mitchell commented ·
Being that the grounding relay is not engaged when you are connected to shore power this would have no effect. Before the inverter connects to a power source it opens that bonding relay.
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derrick thomas avatar image derrick thomas mitchell commented ·

I have seen multiple posts concerning the issue with tripping GFCI outlets, and there seems to be 2 different problems which may or may not be related. In the case where GFCI trips some time after the multi has connected to incoming AC and charging has commenced, then yes you are absolutely correct, changing the relay configuration should have no effect. My comment was directed toward the "other" problem of the GFCI tripping, which has been reported to trip at the same time that the ac input is connected, not after. I have installed several mobile systems of varying manufacturers and changing the relay configuration of some of those with the issue has proven successful in the later scenario described. In the interest of full disclosure, I have not had this issue arise yet on any of the victron equipment I have installed so I can't offer any personal results on that end. Just throwing it out there.

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mitchell avatar image mitchell derrick thomas commented ·
I actually just supported someone with this issue last week. They had bonded the inverter input and output Neutrals. That is the only way the grounding relay can affect a GFCI power source when using Victron. You are correct that other brands of inverter go about this differently and may have other requirements but Victron keeps the Neutral input and Neutral output isolated when inverting which prevents any interaction between the grounding relay and the AC input.
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derrick thomas avatar image derrick thomas mitchell commented ·

"Victron keeps the Neutral input and Neutral output isolated when inverting which prevents any interaction between the grounding relay and the AC input."

Good to know, thanks.

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btempini avatar image
btempini answered ·

Im also adding myself to the list of consumers with this issue. I just reached out to my supplier, and this was their response...

"Currently the issue you are having is a known issue, but there is no solve for it. It is due to a difference in UK, and US outlets. One thing you can check is to see if there is anything else plugged into that circuit. If there is anything else on that circuit you can remove it and try again. If the issue you can plug into a standard outlet if possible."

So run your extension cord inside a building or home (normal outlet) if possible, otherwise your sh*t out of luck...

The fact that this product is even allowed to be sold to RV and Boat enthusiasts in the US, where every outside receptacle legally has to be GFCI controlled, is mind-boggling to me. I bought Victron because I thought it was the best possible product for my specific needs. After spending thousands of dollars on Victron components, I cannot charge my batteries through standard GFCI outlets that exist in every single RV park in the Country.

How has Victron not addressed this to the community yet? We are all waiting...



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delf67 avatar image delf67 commented ·

Quite what this has to do with UK outlets is beyond me. Victron is Dutch.

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derrick thomas avatar image derrick thomas delf67 commented ·
It has nothing to do with uk outlets. Regardless of victron being Dutch, they sell all over the globe, North America being a large consumer of goods specifically designed and built by Victron for use on the North American power grid. As such, this is a major issue which really needs to be addressed. I have dual MP2 in parallel and I have tried every conceivable combination of equipment and settings and powering the system from a GFCI outlet is a no go. I service and install mobile systems in the US and I have had situations with certain customers in which I have had to go with a different manufacturer because of this very problem.
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the-random-task avatar image
the-random-task answered ·

I’ve just installed the MPii in my 50amp RV and same issue here when plugged into a gfci outlet. I’ve only experienced the GFCI trip when the MP switches to float mode. (Input current limiter set to 13a on a 20a gfci plug) I’ve troubleshot the RV AC side by shutting off the main 50amp then turning on each breaker. All breakers seem ok when on except it seems the 15amp breaker in the rv panel that goes to the gfci plugs in the rv are what is tripping the shore power gfci. Wondering if anyone has been able to narrow the issue down to a similar cause and if anyone has any ideas on potential fixes? Thanks

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skopper avatar image
skopper answered ·

I have the exact same problem; same inverter (MPII 2x120). Just installed and it trips my GFCI outlet at home. Plugged into my garage (no GFCI) it does not trip. But this is unacceptable, obviously. My parking spot is on a GFCI circuit. Many campgrounds have GFCI outlets. Cutting ground off a dogbone might work, but what is the real solution? I think a Firmware update is needed. Needed for a long time, apparently. This is widely reported, it turns out. Why do none of the YouTube reviewers mention this defect? I might need to start a channel to get the word out - at least someone does. Maybe going back to some of the more popular reviewers and getting them to complain about it will institute a change.

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Jeremy Albrecht avatar image Jeremy Albrecht commented ·
Sadly. I don't think a firmware update will help. This comes down to a ground leakage issue and best I can tell it would need a hardware revision of some kind.


Victron hasn't responded to this entire thread, though I'm certain they're aware of it, as I've spoken with a Victron engineer in person about this issue.


I wonder if the UL Listed version of this has the same issue?

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skopper avatar image skopper Jeremy Albrecht commented ·
What did the engineer have to say about it?
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Jeremy Albrecht avatar image Jeremy Albrecht skopper commented ·
He was unaware of the issue until I brought it up, but he went digging, including reading this thread while I was talking to him. He agreed about the difference in leakage current standards being a probable cause, but unfortunately he had to leave to catch a flight while we were still talking.
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derrick thomas avatar image derrick thomas Jeremy Albrecht commented ·
Any chance of a follow-up conversation with the engineer?
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Jeremy Albrecht avatar image Jeremy Albrecht derrick thomas commented ·

I'd love to, but I have no contact information for him. We met an an event with many vendors there.

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azfansinnc avatar image
azfansinnc answered ·

Just read this entire thread hoping for a solution. No Joy.

I also have the MP2 wired behind a Hughes 50A EPO in a travel trailer. The 15A GFCI in our storage bay trips when the batteries get close to 100%.

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skopper avatar image
skopper answered ·

While we await Victron fixing this stupid problem, here is what I have done. Get one of these: https://www.amazon.com/gp/product/B09NP7VSNK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

Plug that into the pedestal or home, and then plug something like this into the surge protector: https://www.homedepot.com/p/Commercial-Electric-15-Amp-Single-Outlet-Grounding-Adapter-Gray-U-09/203456716#ratings-and-reviews

You can break the tab off to ensure no contact. Then plug your RV into that adapter. This is all so stupid, but it works. Your RV will be protected from surge and any other fault, including brown-out, will be taken care of by the Multiplus. If they included surge protection in the Multiplus, then all we would need is the ground eliminator, which is still stupid.

If this is so difficult for Victron to fix (i.e., no firmware update can fix it) then they should just give away a combined device that does what I have done with multiple steps.

VICTRON - why are you not replying to this thread? Just fix it already. PLEASE.


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wyobarker avatar image
wyobarker answered ·

Any update to this issue?


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wincio12 avatar image
wincio12 answered ·

I am having the same issue. Multiplus II 2x120 trips any GFCI breaker. Fifth Wheel does not trip the breaker when the MPII is not in the circuit.

Victron - Any update?

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derrick thomas avatar image derrick thomas commented ·
@Guy Stewart (Victron Community Manager) this is a discussion that seems to surface often. Has this been ran up the chain at all with Victron techs? Do you have anything to add?
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