Xantrex inverter grounding problem

[Pizzazz]

A buddy of mine recently bought a H43 with a Xantrex SW2012 inverter and we are having problems connecting it to shore power. The boat is wired for 50A dual phase input (black and red hot wires) but the second phase does not seem to be connected to anything.

The first phase (black hot wire) goes to the inverter and then to the boat. It appears though that the inverter is always grounding neutral to ground which trips the dock box. Our temporary solution is to disconnect ground (green) wires on incoming and outgoing AC to the inverter but connect them together so that the rest of the boat is grounded direct to shore power. This leaves the inverter ungrounded. We installed a manual switch to ground them to the inverter when away from shore power but it is not an elegant solution.

My understanding is that good inverter chargers ground the neutral when inverting but then release it when connected to shore power. That is what my Heart Interface does. This Xantrex does not do that and there is no menu setting to change this option. Is this a problem with the inverter (may be an internal fault somewhere), is Xantrex just lazy to implement this function or is there another better solution short of replacing the inverter?

Thank you,
SV Pizzazz

[smac999]

is the 2012 rated for 50a passthrough? it probably shouldn't be the first thing in line with the shore. normally it's part way through the boat with non inverted loads leaving before the inverter.

is it a GFI or ELCI breaker that is tripping? if the intertver is wired wrong it's common to trip those. but a normal breaker should not be, even with the inverter also grounded. so my guess is you are triping a GFI.

the 2012 does ground and unground the neutral like any marine rated inverter.
it's possible it's broken. but an extra ground bond on the the boat will not trip a standard breaker. only trip a GFI.

[Pizzazz]

Thank you for the reply. The dock box breaker is tripping, sometimes after one second, sometimes after 10 seconds. These are new docks, so I am guessing that they have a built in GFCI. Many people on the new docks are complaining, I guess because they use non marine inverters. So now we know what the problem is. The guy needs to either manually ground the inverter every time he uses it or buy a new inverter. Thank you.

OK. This case is solved.

[smac999]

no you need to fix the wiring. if it's properly wired it will not trip.

I bet you have a single neutral bus on the boat. you need to seperate the shore neutreal bus from the inverter output neutreal bus.


all those boats having dock issues. have issues on the boat.

[Pizzazz]

I see your point. The boat has two neutral buses but the second is not used for anything. Logically, you can’t split the inverter loads because some loads need to work on both inverter and shore power. Otherwise it is a major inconvenience. The right solution is for the inverter to lift the ground when not in use, like all marine inverters do.

If the ground and the neutral are connected the dock box does not like it (most likely due to a built in GFCI. Older docks did not care as much. One more reason to buy marine equipment only.

[smac999]

Inverter chargers lift the ground bond ~15 secs after the boat is plugged in. The gfi will trip in the first 15 secs. This is the problem. But If it’s wired correctly it will not trip a gfi. Only when it’s wired wrong with the input and output neutrals joined on the same bus.

Inverter chargers pass through power. Loads automatically run off either shore or inverter. It’s all seemless When done right.