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Anyone using a generator to charge batteries on MPP LV6548?

bones1 said:
This made me think about it. I have a new furnace with all the fancy stuff and I think I will add a protector to it now. Thanks.
Click to expand...
Part of this surge and collapsing sine wave issue is lack of proper installation of these AIO inverters. The AIOs have AC ground input and output which create ground loops in the circuit. Then the AIO manufacturers bond the Neutral and Ground together in DC mode, to make even more ground loops…argggg. When going from bypass mode (AC input to AC output) to battery a significant surge occurs. One solution is to cap the AC output grounds at the panel, if grid tied. Then research the AIO to eliminate the NGB issue.
Lastly, add a very robust SPD to AC line input side, like a military spec grade unit (like a bad wolf USA). All other down stream panels and HVAC equipment I used typical residential SPDs to cut the spikes down.

Hope this helps.

-Jay
 
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Thanks for the good info. I am not grid-tied, do I still need an SPD at the 50a input AC side?. My input comes off my main panel on a 50 A breaker. I can see at the AC out and then at the HVAC itself.
Maybe this for the inverter output panel
images
and this at the furnace connection
shopping
 
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bones1 said:
Thanks for the good info. I am not grid-tied, do I still need an SPD at the 50a input AC side?. My input comes off my main panel on a 50 A breaker. I can see at the AC out and then at the HVAC itself.
Maybe this for the inverter output panel
images
and this at the furnace connection
shopping
Click to expand...
Any input and output should ideally have a fast fuse or SPD. If your AC input is not tied to grid, then you won’t need one there.
 
You may actually need two whole house surge protectors. The inverter is like the man in the middle and can get hit from both sides. If you are grid connected in any way, you may want a SPD somewhere between the meter and inverter. Also between the inverter and load. It’s actually more important because most sensitive devices are damaged by other devices in the home rather than lightening, downed lines or external sources. In the home, air conditioners are the primary cause then other inductive load disconnects. One member here had damaged immediately after using the burner igniter on his stove. 298A216F-EFC2-4C74-8023-A4E134DDE1FF.jpeg FABB9533-35BB-4A1D-9F52-DA7B4F3FECC1.jpeg
 
Skypower said:
You may actually need two whole house surge protectors. If you are grid connected in any way, you may want a SPD somewhere between the meter and inverter. Also between the inverter and load. It’s actually more important because most sensitive devices are damaged by other devices in the home rather than lightening, downed lines or external sources. In the home, air conditioners are the primary cause then other inductive load disconnects. One member here had damaged immediately after using the burner igniter on his stove. View attachment 130220 View attachment 130219
Click to expand...
Yep! Both sides of the inverter I/O and anywhere else a surge can enter the system.

That’s the brand I am using too.
 
There is another class of device called a fero resonant transformer
It provide both surge brown out protection and ride through for sensitive electronics

Surge protection is better than nothing but I am not sold on these things unless you can get them cheap
Square D stuff is pretty cheap.....
 
It was common practice to use one to one transformers in large shop machinery to reduce interference/spikes, but in not seeing it anymore. I’m seeing filtering, surge arrestors and requirements for ground rods at each machine now. Probably trying to make it cheaper. If we omit the rods we tend to get machines with a run-amok-us. Those transformers weren’t cheap and heavy as hell. On new homes it’s now required to have a whole house surge protection and under some circumstances electrician have install them when working on your home or when sold depending on local codes. Most common and good bang for the buck is Square D, but yes there’s always better. Nothing will save your precious 80” 8K from a direct or close lightning strike. There are some $400 Emp/surge arrestors but how much do you need and will that actually help? Not like they’ll answering a complaint if SHTF?
 
You are correct. Cvt or fero resonant transformers are a more involved but superior solution.
 
Skypower said:
It was common practice to use one to one transformers in large shop machinery to reduce interference/spikes, but in not seeing it anymore.
Click to expand...
That can be a lot of things for a lot of reasons.
Early VFDs need line and load reactors to deal with harmonics.
If you want to connect a VFD to a power system with un-grounded Delta power you need isolation and a good ground.

Today's drives are better and less sensative to harmonics and noise.
They still blow up when lightning hits the switch yard.
 
I have problems charging through my MPPs as well. I think my issues are to do with my generator, not the inverters. From what I understand they are finicky about power and my generator is not "inverter duty" rated. I am currently generator shopping as I am all out of other options.
 
New England Rhinoceros said:
I have problems charging through my MPPs as well. I think my issues are to do with my generator, not the inverters. From what I understand they are finicky about power and my generator is not "inverter duty" rated. I am currently generator shopping as I am all out of other options.
Click to expand...
I don’t know what that means

Don’t buy a generac?
That good advice to anyone lol
 
If anyone was interested, don’t have to be an expert to see issues;

Grid
289C2A3C-8DBC-4FE8-91FF-3AE2F843F19C.jpeg
Mpp LV6548 on battery E4CEA9F2-8C99-45C4-9491-D2932AE1C940.jpeg
Predator 9500
947E8C47-3E58-4655-8343-5EE533699CC2.jpeg
Chicago Electric 7000 conventional generator. F047941B-C66C-465F-B468-BD444B9081C8.jpeg
 
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DPC said:
I don’t know what that means

Don’t buy a generac?
That good advice to anyone lol
Click to expand...
I didn't either but I am learning. What it means is I have a $1600 generator in my yard that doesn't charge my batteries due to total harmonic distortion if I understand correctly. See the photos above from Skypower.
 
timselectric said:
The generator isn't bolted down.
It's all jiggly. lol
Click to expand...
It’s funny you say that because that thing was shaking and the reading was so bad I thought it was a bad connection. I put it under full load and it handled it well but it definitely wasn’t a bad connection. Just the way it is. The waveform did get a little bit better but it only subjective.
 
New England Rhinoceros said:
I didn't either but I am learning. What it means is I have a $1600 generator in my yard that doesn't charge my batteries due to total harmonic distortion if I understand correctly. See the photos above from Skypower.
Click to expand...

That’s not all that uncommon
Two pole machines don’t have a lot of slots in them
Think of a step pyramid
The nature of a distributed winding with few slots means less choices in the engineering of the winding and smaller it is in power output the more likely your going to get some odd harmonic distortion

Looking at the way forms I see a lot of distortion
That unit is probably unloaded for the test
That might clean up with a load on it
A cap run motor might soak up a lot of that distortion and let the charger pick up

Meter looks like a Chinese 100 dollar scope meter
That’s something I would use with a set of fused leads ( but I would use it )
Only CAT 2 or 3
More of a bench electronics tool than a power electronics tool
 
Link to a Chinese scope meter

I don’t know what unit is on shots in the previous posts
For residential use under 250 I think they are probably fine but buy some fused leads
Quality leads from fluke or something so you don’t have to worry about an accident

kkm828 High Clarity Intelligent Graphical Digital Oscilloscope Multimeter 2.4 Inches Color Screen 1MHz Bandwidth Oscilloscope
 
I myself have an old Eaton ups for back on my sump pump
It’s not at all willing to except power from my old Onan lk
It could be harmonics and noise
I have removed some bad filter caps from it
It also gallops a long 1800 rpm with one cylinder

I have another a small 3600 rpm Kohler the ups is fine with

I should put a scope on them to see what the problem really is
But it’s not unique to cheap generators
 
DPC said:
Link to a Chinese scope meter

I don’t know what unit is on shots in the previous posts
For residential use under 250 I think they are probably fine but buy some fused leads
Quality leads from fluke or something so you don’t have to worry about an accident

kkm828 High Clarity Intelligent Graphical Digital Oscilloscope Multimeter 2.4 Inches Color Screen 1MHz Bandwidth Oscilloscope
Click to expand...
Yup, it is a cheap oscope. What’s infuriating is every time you turn it on you have to scroll and push buttons for while to get a sine wave. It doesn’t friggen remember the last settings or do it automatically. Once it’s running it does have a nice visual. Despite the 10x reduction lead it still managed to hurt something so I get a bottom clipped view if I look at a 240v source. Yeah, I’m in the market so I can set this on up on the target range for all the aggravation.
 
Skypower said:
It takes 7 pages in the manual to get WatchPower setup. There’s the first clue.
Wasted two days of my life struggling and gave up. Installed Solar Assistant and it was easy. A half an hour after receiving it, it was working.
Click to expand...
I have tried and failed to get WatchPower running. Total junk! I downloaded the Solar Assistant app. I hope it will work.
 
Skypower said:
Yup, it is a cheap oscope. What’s infuriating is every time you turn it on you have to scroll and push buttons for while to get a sine wave. It doesn’t friggen remember the last settings or do it automatically. Once it’s running it does have a nice visual. Despite the 10x reduction lead it still managed to hurt something so I get a bottom clipped view if I look at a 240v source. Yeah, I’m in the market so I can set this on up on the target range for all the aggravation.
Click to expand...
Good test equipment is expensive
I can’t afford it

Since you are already playing with these things what recommendations do you have?

Off and on I have looked at this mustool meter
Says it’s CAT II and rated for 1000 volts ( I highly doubt )
I do a fair bit of testing and head scratching on soft starts and in sophisticated stuff it would be nice to be able to put a scope on and see it scrs are firing or things are happening as I might expect
I don’t really do anything that would require a real scope
I would just like to be able to see what my meter sees

Any thoughts and observations on what you have and think would be appreciated

I wish the Chinese made something in the 100 dollar range that was safe to 1000 volts and simple for basic troubleshooting
I don’t need a real scope just a visual aid
 
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OleMan2765 said:
Searched forum, and did not find any results.
Have two LV6548's split phase.
Have generator connected to input side.
L1 and L2 connected, and even swapped connections from genny to L1 and L2. (Read somewhere that might help.)
No luck. MPP's reset as if to sync with the AC, but never completely connect.

Followed diagram sent with system that says it can be done.
But no luck.

All I wanted to do is charge batteries when we have a few days of no sun.

Alternatively, I have shut down the system, and attached battery chargers to the batteries, and wake them back up. Just a pain.

My generator is a Generac 7500XL. Output is 30A 220vac.
Click to expand...


I diverted from original plan to use my MPP Solar inverters for battery charging once I found out they require to be in bypass in order to charge. I instead bought 2 AIMS 48v (51.2v with LFP charge profile), 18.75a standalone chargers, a charger to put on each leg of generator, and will charge battery bank while inverting (not requiring bypass).

I will still wire a generator circuit with a breaker (to leave off usually) to the AC inputs of the MPP Solar in case for emergency charging, but will likely never use them for charging as long as the AIMS 48v chargers function properly. I know Signature Solar and others also sell adequate 48v chargers, somewhere between 18 and 20 amps as well. Could buy 4 of them if you think you needed more charging amps.

There's a thread on here somewhere comparing a few different standalone charger models.
 
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DPC said:
I wish the Chinese made something in the 100 dollar range that was safe to 1000 volts and simple for basic troubleshooting
I don’t need a real scope just a visual aid
Click to expand...
They’re all safe at a 1000V as long as you recategorize them as unsafe and insane fireworks. As far as selection of the next one it’ll be based on the number of stars on Amazon and how little I want to retire on. So no, I probably don’t have a good suggestion?
 
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