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Continuity between line and neutral (Black and White wires) when not connected to power

dpgator33

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I'm at the very end of my first solar/battery upgrade project, on my travel trailer. Big picture details - 2x200w Solar, Victron 100/50 MPPT controller, Victron Lynx Distributor, Victron Multiplus 3000VA (120v US model). 2x200Ah LifePO4 batteries (Chins) 12v. Victron BMV 712 w/Smart Shunt going into DC bus on Lynx distributor. 30Amp shore power plug. Factory distribution panel with both AC and DC is still in place, with AC-DC converter disconnected.

I've got everything connected, double-checked all the terminations, and am about ready to hook up my batteries to the whole setup. I do have a battery disconnect switch also. Battery + goes to fuse block, then to battery cutoff then to Lynx distributor/busbar +

My last cable run and termination is the AC out from the Multiplus to the AC side of the distribution panel. Per recommendations, I am using marine grade 6/3 stranded copper wire. The 6/3 stuff is super thick and not very flexible and proved very difficult to get wired in to the Multiplus terminals. So much so that I had to keep trying to get them inserted properly and secured, and could have maybe compromised/lost a bit of a couple of strands from either/both wires. I don't think that in and of itself is a huge deal given the number of strands involved, but I wanted to mention is. Also, the terminals for these cables are super close. Out of an abundance of caution, I wanted to check that there was no continuity between the line and neutral wires specifically, like if I have a loose strand that might be making contact with the other wire, even though I don't visibly see that happening, they're so small and the terminals are so close I could possibly miss it. I was not expecting there to be any continuity, but when I hooked up my multimeter, I indeed did get a tone. I took that as an indication that the wires were indeed touching and I needed to re-terminate, so I did. Still getting tone. I checked at the distribution panel as well and also got a tone, and those terminals are nowhere near each other, so now I'm a little unsure of myself. I'm more familiar with DC, so I at this point I am kind of wondering if this is expected.

In doing a little research, I understand that if you have a device turned on in anywhere in the circuit, you should get a tone for continuity. I don't have anything turned on, and there is no shore power connected (I didn't check for voltage, and this may not be relevant, just though I'd mention) I'm pretty sure I even turned off all the breakers and still got tone. I'm not at the trailer now, but I will confirm that again later.

My questions is, am I supposed to get continuity at these points and I should I not be worried about it? I don't want to test anything similar here at the house, obviously with live power coming in that seems a little dangerous potentially.
 
Unless you are popping circuit breakers or have too much unexplained AC load current I would not worry about it.

Many devices have EMI bypass caps on AC lines that may show momentary reading on ohm meter tests. The inverter output will have a larger capacitor for switching spike filtering that will take a longer time to charge up by ohm meter. A low frequency (heavy transformer) inverter has continuity through the output side AC transformer winding so it will look almost like a short circuit with maybe less than an ohm resistance.

A 3000 VA inverter only needs 10 gauge output wire so even 8 gauge would be overkill. The terminals will not likely be large enough to take #6. You would be better off running #8 from inverter to output breaker.
 
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Unless you are popping circuit breakers or have too much unexplained AC load current I would not worry about it.

Many devices have EMI bypass caps on AC lines that may show momentary reading on ohm meter tests. The inverter output will have a larger capacitor for switching spike filtering that will take a longer time to charge up by ohm meter. A low frequency (heavy transformer) inverter has continuity through the output side AC transformer winding so it will look almost like a short circuit with maybe less than an ohm resistance.

A 3000 VA inverter only needs 10 gauge output wire so even 8 gauge would be overkill. The terminals will not likely be large enough to take #6. You would be better off running #8 from inverter to output breaker.
Thanks for the explanation. In the guidance I reviewed for the Multiplus, The 6/3 wire was recommended due to its "power assist" functionality that "borrows" power from the batteries as needed if shore power isn't sufficient to handle the load. So while I have 10/3 marine cable running from the shore power plug to the AC input on the Multiplus, I use #6 on the output to the distribution panel. I don't envision that ever being a problem given the size of our rig and estimated maximum draw. I only say this as an explanation as to why, not justifying it with any rock solid scenario where it would be useful/required. I do find myself now having to consider replacing the #6 with #8, for nothing else than to be more confident in my terminations.

edit - 'guidance' not from Victron, but rather a blog type post about a person who did a similar project, who knows more about electricity than I do.
 
I also forgot to run the comm cable for my battery monitor display that also routes to the distribution panel area of the trailer, so I'm already having to do most of the work required for this...#8 cable ordered. What's another $140 into this project anyhow ;)
 
With a 50 amp AC in connect relay it should have terminals capable of #6. If you flare the strands it can be difficult.
 
They are capable, just really tough. This clip explains and shows it pretty well, for anyone interested in what I'm talking about. I'm glad I re-watched it, because I now recall an important step that should make this a lot easier, and that it to use ferrules for the termination, and I happen to have a bag of about 100 #6 ferrules that I honestly don't know what reason I have them for.

 
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