Planning to install a Victron inverter/charger which has a automatic transfer switch. My AC neutrals all tie to a common buss and then disappear behind non-removable structure so I can't see which ones go with the specific hot leads. It would be much easier to include all the neutrals when connecting to the inverter transfer, however, I don't know if having the neutrals that do not have respective hot leads connected when using inverted power is an issue. If so, anyone know an easy way to identify which neutrals go with which hot leads?
Do I need to find neutrals
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Bud
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You can use a signal wire/circuit tracer. You have to disconnect the nuetral from the bus, hook the signal generator to it then go hunting to outlets ect.. with the receiver to find signal.
Bud
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I have installed two Multiplus II inverters and because the inverter switches the L1, L2, Neutral and ground at the same time, I simply connected the inverter in between the shore power/genset switch output, and the panel busses for all 4 of those interfaces. I don't think there's any need to isolate specific neutrals.
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You should move the neutrals for inverted loads onto a separate bus. Otherwise if you plug into a dock with an ELCI breaker with the inverter on and let it auto-transfer, you may trip the ELCI breaker.
The inverter bonds the output neutral to ground while inverting and releases that bond when passing shore power through. If all of the neutrals are tied together, the input neutral will be bonded to ground for the first few seconds after you plug in before the inverter switches over. If there are any loads drawing power that don't go through the inverter, that neutral / ground bond will cause an ELCI trip (the inverter loads won't be an issue as they won't draw shore power until the inverter switches over and releases the N/G bond).
The inverter bonds the output neutral to ground while inverting and releases that bond when passing shore power through. If all of the neutrals are tied together, the input neutral will be bonded to ground for the first few seconds after you plug in before the inverter switches over. If there are any loads drawing power that don't go through the inverter, that neutral / ground bond will cause an ELCI trip (the inverter loads won't be an issue as they won't draw shore power until the inverter switches over and releases the N/G bond).
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The short answer to your problem. Turn off all AC power to and on the boat. Disconnect all the neutrals. Then due a continuity test on each neutral. Label it. To do this you will need a multimeter, a 50’ piece of wire and two alligator clips.
Read rslifkin’s post as to why.
Read rslifkin’s post as to why.
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If all neutrals & hots are downstream of the inverter then there will be no problem with neutrals. However when switching from shore to invert, then overload may occur unless inverter outputs the same amps as shore output.
Reverse polarity will light up when inverting if all hots are not downstream of inverter. Shore cable end will be hot at neutral if still plugged into boat end.
Thus a good idea to have separate inverter only circuits.
Reverse polarity will light up when inverting if all hots are not downstream of inverter. Shore cable end will be hot at neutral if still plugged into boat end.
Thus a good idea to have separate inverter only circuits.
no easy way as all neutrals must be removed from buss bar so they can be individually traced to hot at breaker OR neutral end at outlet.
jgwinks
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If ALL your AC circuits will be fed by the inverter, there would be no reason to isolate the neutrals. If the inverter is to feed only some of the circuits, then those neutrals will have to be isolated. For example, you probably don't want a water heater to run off the inverter, it would kill the batteries in a few minutes. On my last sailboat I did wire the inverter to run everything, but I had to make sure the WH was turned off before turning the inverter on. My present boat has two 30 amp power inlets and a pass through inverter. The original wiring had all the neutrals for both inlets on the same bus, and when I installed the inverter I had to isolate them. It now has three separate neutral busses to accommodate the three different AC sources. The neutrals for each source must be isolated from each other or you will trip the ground fault protection on a newer shore power installation. In my case separating the neutrals was pretty easy as everything was wired with triplex wire, I could see which neutral went with which hot wire.
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First, electrically, and or safety wise there is no reason to create a inverter neutral buss.
The problem is as posted above you will trip the ELCI at the dockside shore power. Here is how it works.
When you remove the AC input from the multiplus a relay connects the AC out Neutral to ground. This provides your safety ground-neutral bond while inverting. This happens wether the inverter is inverting or not.
When you connect the shore power the ELCI sees this ground-neutral connection as a current leakage and immediately trips the power off. At the same time the multiplus removes the ground-neutral connection.
But... the multiplus is slower than the shore power ELCI's tripping.
If... you could slow down the ELCI just a second, probably just a few miliseconds in reality the multiplus would have time to remove the neutral - ground connection, but... that is not the case.
So... you need to either isolate the neutrals, or install a isolation transformer.
The problem is as posted above you will trip the ELCI at the dockside shore power. Here is how it works.
When you remove the AC input from the multiplus a relay connects the AC out Neutral to ground. This provides your safety ground-neutral bond while inverting. This happens wether the inverter is inverting or not.
When you connect the shore power the ELCI sees this ground-neutral connection as a current leakage and immediately trips the power off. At the same time the multiplus removes the ground-neutral connection.
But... the multiplus is slower than the shore power ELCI's tripping.
If... you could slow down the ELCI just a second, probably just a few miliseconds in reality the multiplus would have time to remove the neutral - ground connection, but... that is not the case.
So... you need to either isolate the neutrals, or install a isolation transformer.
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