heirloom hamlet
life my way
Anyone know why there is such a spark when you plug something into the ac output on the LV2424s? Happens every time. Is it avoidable?
Spark Pop On LV2424
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gnubie
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There shouldn't really be any more of a spark than if you plugged something into a wall socket. If anything, likely less because the wall socket is backed by a very low impedance supply, ie the mains (grid), while the inverter is comparatively lightweight. Perhaps the issue is the depth of the pins in the inverter's sockets, ie they are closer to the surface making the arc appear to be worse? Perhaps there is something going on a high (10+kHz) frequencies?
My own experience is that, as expected, inverters are less bitey than the mains.
My own experience is that, as expected, inverters are less bitey than the mains.
heirloom hamlet
life my way
Idk, but all there is is a chopped 12awg ext cord wired to the inverter's output and am plugging in typical grounded and ungrounded plugs into it...ext cord, led lights, phone or laptop charger...and they always noticably spark more than normal. It isn't a single spark either. If you're fiddling while trying to get it inserted, and it makes then loses and remakes contact, it will spark each time. I should run experiments to see if any cords or scenarios DO NOT create a spark.
gnubie
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If you jiggle and dither while plugging into a standard wall outlet you'll get arcing a plenty too, except it will be a lot more violent due to the low impedance source - the mains. Maybe you are used to the larger splat from a standard outlet vs the lower level arcing from an inverter? Maybe you are just being more aware of the situation when plugging into the inverter?
If I had high enough grade audio recording equipment I'd make some recordings of how things sound here in 230V land.
If I had high enough grade audio recording equipment I'd make some recordings of how things sound here in 230V land.
heirloom hamlet
life my way
Maybe. Seems out of the ordinary. My gut tells me there is a different dynamic of some sort and I have learned to pay attention to that dude.
MrNatural22
?SW sunshine =⚡️⚡️lit up thru the darkness✌️
Did you have the load turned on on the ac devise you were plugging in? That might be the reason.
Just guessing?
Just guessing?
heirloom hamlet
life my way
No, today just an unplugged power cord and a small charger that was off. An off fan. It's odd, I thought that it would be a smaller load than the mains, too. But it's consistent.
Ampster
Renewable Energy Hobbyist
Trace it back from the terminal of the chopped extension cord to the inverter with a multimeter. What kind of voltage values are you getting?
Ampster
Renewable Energy Hobbyist
Is there a circuit breaker on that?
RCinFLA
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Sounds like a bad extension cord socket. Did you measure AC voltages? Sure not hooked ext cord across 240vac terminals on inverter? or L1 or L2 and ground instead of neutral. Neutral and ground on inverter is floating until bonded together at breaker box ground strap. I get the feeling you are just trying to do a quick test on inverter AC output before completing AC hook up.
Ampster
Renewable Energy Hobbyist
@ecualibrium
How did it get resolved? People are naturally curious and would like closure. There may be a lesson that we can all learn.
How did it get resolved? People are naturally curious and would like closure. There may be a lesson that we can all learn.
heirloom hamlet
life my way
Well, it really hasn't been resolved. @RCinFLA is correct, I am just connecting and testing the MPPs and everything else en route to my full system hookup. The LV2424s have been sitting waiting while I get the cells in, charge and top balance, find a BMS and learned to connect them. I've done everything now except make a permanent mount for the x24 250w panels.
So you were on to something too when you asked about the circuit breaker. I am waiting for the 25a breakers to arrive, but, no there is no connected breaker just yet. That is unless the LV2424 has a built-in inverter fuse, which it may, I can't quite tell. It took a bit to figure exactly what size breaker I needed after ac leaves the inverter, but I've settled on 25a. I also have to drive in my x2 8ft copper grounding rods and ground the systems. Simply using the ground screw on the units is essentially nothing, as I understand it.
It is all hooked up now exactly how Will did it in his quick video. While I will ultimately have a larger 6awg wire running from the inverter outlet to the breaker, and then aluminum 2 guage from there to the home box, right now it is just a chopped 12awg cord outlet.
And every time plug into it it sparks more than what I consider normal. I'm starting to think it won't always be this way, once I wire to breakers and ground the systems.
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Ampster
Renewable Energy Hobbyist
Since the breaker is to protect the wire you are commiting to using 10 AWG wire on anything past that breaker. Most household circuits are 20 Amps using 12 AWG wire which is pretty common at Home Centers and hardware stores. Some lighting circuits use 16 AWG with 15 Amp breakers. You will find a significant price difference between those size wires.
BTW you never answered my question about the voltage at that chopped 12 awg cord? A useful diagnostic would be to check voltages to ground, nuetral and between each conductor.
RCinFLA
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If all you are trying to do is see if AC out is working before properly connecting to panel, try putting a temporary jumper wire between inverter's neutral and ground terminals. Remember to remove it when doing proper wiring to breaker box.
There shouldn't be, but sometimes there are ZNR's surge protectors and/or some disc caps between neutral and case grounding. Your 'sparks' might be caused by them so connecting neutral to ground should prevent it. Normal main breaker box hookup for inverter AC input calls for separate ground and neutral wires to breaker box. Per code, there should be one point of connecting neutral to ground in the main breaker box.
Never rely on metal conduit to make the only case to case electrical connection. There should be separate wire connecting between cases.
It is a good idea to run through manual several times before powering up. The most critical things relates to battery charging and battery charging currents. You do not want to allow any default settings to hurt your batteries.
It is a complicated beast that can be daunting until you get familar with it. Add to that, some sections have a somewhat mutated Chinese to English translation. Some menus do not seem to make common sense, likely result of software engineering determining how it should be done.
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Ampster
Renewable Energy Hobbyist
Would that show up as voltage between neutral and ground?
Yes it happens and the only way it is avoidable is the device you are plugging in has a power switch and you turn it off before plugging or unplugging. Then the sparks happen inside the devices power switch where you can't see it.
The same thing happens when you plug something into your house hold power outlets too. There is a reason why power outlets and switches are not made out of clear plastic.
heirloom hamlet
life my way
Well, my setup is a distance away from the homes it will be powering. So I'll have the inverter go to this 25a breaker and then from there it will travel about a hundred feet. That's what the 2-2-4is for. It will run into a breaker box on the home and be distributed with 14awg and 12awg into a few 15s and maybe a 20 in the space.
The two current MPPs read 119.7 and 119.5. These are those All-in-one units, so I'm not sure what to get a read on other than the ac out plug I've attached.
heirloom hamlet
life my way
I have not had the spark one time since grounding each LV2424. I drove two 8' copper rods into the ground six feet apart and connected them with 10awg solid copper.
There is a screw and washer on the bottom of those units with a ground logo by it. Best I could tell, they wanted me to make my connection there for the entire box. The input has a ground plug-in and I saw Will run his output ground wire to that input ground, too.
Haven't seen a spark since, and it was significant, made a pop sound. Also, the BMS' went on in between that spark question and the possible resolution.
There is a screw and washer on the bottom of those units with a ground logo by it. Best I could tell, they wanted me to make my connection there for the entire box. The input has a ground plug-in and I saw Will run his output ground wire to that input ground, too.
Haven't seen a spark since, and it was significant, made a pop sound. Also, the BMS' went on in between that spark question and the possible resolution.
There may not be sparks but there might be a current flowing. Do you have a clamp meter? If so, might be worth clamping over the earth line. There should be no current flowing to earth (under normal circumstances, obviously). If there is you have a ground loop fault, usually caused by having multiple neutral-to-earth connections.
Ampster
Renewable Energy Hobbyist
The cause of the spark apparently was because the inverter was not grounded and the OP had not wired it to an electrical panel that would have been ordinarily grounded through that electrical panel. He had directly wired an extension cord to the inverter which I presume caused the issue. @RCinFLA earlier had suggested a fix but we never heard back from the OP and it was nagging me so I asked him to close the loop so others reading this might see the cause and the solution. It is no longer an issue as far as I can tell.
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