Generator for mpp solar lvx 6048?

Lstyles

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May 31, 2021
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Planning an off-grid solar vacation home in Baja and from reading on the forum it seems like the MPP Solar lvx 6048 is highly thought of. Plan would be to parallel two of them to support 120/240 service and a solar array of about 10-15 kw and battery capacity of about 20-30kw. The sun is fairly constant year round in Baja so I don’t anticipate many days where I wouldn’t be able to charge the batteries back up to 100% but it might be a good plan to have a back up generator. The mpp site suggests using inverter generators as the power is cleaner. They provide the following specs for the generator to be compatible:
1629484098298.jpeg
I hate to put in something overly large as I think it will get very little use and if we do run into times with little sun we can decrease our energy use (it’s a vacation home). Does anyone have any real world experience with using back up generator with these mpp solar units? Another alternative would of course be to increase battery bank size or use a solar generator (ie separate additional battery) in case primary battery bank has issues. Any thoughts or ideas would be appreciated!
TIA,
Lori
 

eabyrd

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Planning an off-grid solar vacation home in Baja and from reading on the forum it seems like the MPP Solar lvx 6048 is highly thought of. Plan would be to parallel two of them to support 120/240 service and a solar array of about 10-15 kw and battery capacity of about 20-30kw. The sun is fairly constant year round in Baja so I don’t anticipate many days where I wouldn’t be able to charge the batteries back up to 100% but it might be a good plan to have a back up generator. The mpp site suggests using inverter generators as the power is cleaner. They provide the following specs for the generator to be compatible:
View attachment 60972
I hate to put in something overly large as I think it will get very little use and if we do run into times with little sun we can decrease our energy use (it’s a vacation home). Does anyone have any real world experience with using back up generator with these mpp solar units? Another alternative would of course be to increase battery bank size or use a solar generator (ie separate additional battery) in case primary battery bank has issues. Any thoughts or ideas would be appreciated!
TIA,
Lori
I put the generator input after the inverter so I didn’t have that concern. If it gets so bad I need to charge batteries from the genset I have a 48 volt charger
 

RCinFLA

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Jun 21, 2020
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Inverter-generators work well because they have tightly controlled frequency and fairly clean sinewave. May not be able to use ECO mode where engine rpm reduces based on load. In ECO mode, when load is applied the inverter-generator output voltage dips a bit while engine spins up to higher rpm to meet new load demand.

For regular synchronous generator with mechanical govenors the consistancy of rpm is as important as their frequency. Any instability of rpm control will cause problems with inverter achieving and maintaining phase lock with generator. That is the <0.3 Hz per sec. spec which could also be stated as <18 rpm variability per second at 3600 rpm for 60Hz generator.
 
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rplarry

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Feb 17, 2021
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You definitely need a gen back up. Yes Baja is sunny but once you start relying on the sun you realize how many cloudy and partially cloudy days there really are. The worst I have experienced where I am in northern Baja is 11 days in a row of clouds. In those 11 days I put 23 hours on my generator to keep the batteries up. As I said that was the worst in the 23 years I have been down there but it is not uncommon to have 2 and 3 days of clouds.
All that being said the size of your gen set will depend on how you plan on using it. If your system is designed so that the inverter runs everything and you only need the gen to charge batteries then you don't need a very big gen set. Just one big enough to charge your batteries and at the same time pass through enough power to run your house. If on the other hand your system can't run all your appliances and power tools, welders, etc. then you will need a generator to run those consumers separately from your inverter. That is what I have to do if I want to do some welding, then I need to start the generator for that.
where are you planning on making your home in Baja?
 

Lstyles

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May 31, 2021
Messages
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Thanks real life input on solar use in Baja. We will be building in Punta Chivato near Mulege on the gulf of California. Weather down in BCS is sunnier than the northern part of Baja (which is often like San Diego where I grew up). It’s a little different down there as there are fewer cloudy days and it’s actually more cloudy during the summer months. Summer is unbearably so we will not be there during the summer. The summer is when you need the A/C most so that helps with reducing power needs as well (plus we hate A/C). I have our system plans above but it takes into account the rare possibility of 4-5 days of clouds when we would need to cut back on energy use. As the home is a vacation home we would rather design the system to what will be sufficient for 95+% of the time and if things get bad we can go home/hotel as a last resort. The system outlined above seems to be working for others in the same area without generator use. I am actually now thinking of going without generator all together and just put together a DIY battery (16 x 280ah cells) to use as back up system. Alternatively, maybe just a small portable generator for emergency use. REALLY want to avoid ALL hydrocarbon use.
 

rplarry

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I like the Punta Chivato area a lot. I have friends down there. I'm up in BoLA October through June. I spend the summer months at my house in San Diego near La Jolla so not too hot out here with the on shore flow. Good luck on not using any hydrocarbons, but you will certainly reduce your foot print in Baja. Instead of enlarging your battery bank for the occasional need, I would get more solar panels. Batteries are a consumable and need to be replaced every so often but solar panels will most likely out live us unless you get a seagull to drop a clam on one of your panels like I did. Anyway even on cloudy days you get some charge so if your battery bank is adequate for your system then just get more panels to help charge them on cloudy days. Panels are relatively cheap now so a much better investment.
What are your plans for batteries? LFP or something else?
I am not familiar with the MPP solar inverters but I just looked at them and they are very inexpensive compared to what I spent on my Outback inverters 20 years ago. Although 20 years of trouble free service is something worth paying for. The times they are a changing.
 

Lstyles

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May 31, 2021
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B of La is very nice as well and I don’t think the weather there is that much different than Punta Chivato. I was born and raised in La Jolla by the way. Your suggestion for more solar panels is also something we considered as we have a relatively large lot (7/8 acre) and a modest sized home so lots of real estate to put more solar panels up if rooftop system is not sufficient. I may just wait on that decision (eg. generator, back up battery, more panels) and see how things go.
As for inverter choice, my solar installer is suggesting an 8k Outback as well but it’s SOooo much more expensive and I could literally buy several of the Mpp solar units with the same $$$ as the Outback. Also, the experience using the Mpp solar units seems to be pretty good (Will Prowse uses them in his system and he seems to be very focused on using quality products).
 

rplarry

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Again I have no experience with the MPP inverters so take what I say with a grain of salt. I think you stated in your original post that you were going to use 2 MPP inverters which I think is a good idea in that if you have a problem you have a back up. That is why I have 2 Outbacks. Never needed to but I had a back up if necessary. The only time I had a failure was with my battery bank so now I have 2 banks separated by a 1-2-both battery switch. When you are down in Baja as you know there is no store to run over to, to get stuff and it is a long drive to San Diego. I think you are on the right track, just go down there and enjoy the place and add equipment as you need it. Talk to your neighbors and see what they do to solve a particular problem.
Keep your eyes out for a guy name Bill Oltman a retired San Diego firefighter I know he's down there somewhere near Chivato. Tell him Larry says Hi.
 

self_sufficient_25

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I have 2 lvx6048 inverters. The draw back with them is the stand by current of 140w each, When used of gid.
Also when connected to a generator your power is limited to what the generator can supply.

Other inverters like sunny island and some magnum inverters. Will assist the generator when there is a higher load.

Also if you want to connect the generator to the Lvx6048 it will need to be split phase (240v).

As a alternative, I use a 3500w 120v generator with an external charger. It works well.
 

rplarry

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Feb 17, 2021
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Self,
When the lvx inverters are in parallel does one inverter sleep and wait for a large load before it wakes up and helps the master inverter? If so what is the watt draw in sleep mode? If not then 280 watts is a fairly large draw. If I did the math in my head correctly thats about 5 amps at 48v. That can't be right I must have done something wrong.
 

OffGridInTheCity

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I have an eu3000is connected to an ATS to the input of my MPP Solar 3048LV. It's a "3000w" generator - but on gasoline I can only get 2,200w of charging before it starts bogging down. With the propane conversion I get 2000w. So maybe size your generator to how much charging watts you want to achieve and wiring. 2200w / 120v = 18amp wiring needed. The MPP Solar let's you select the "Charging Amps" as the way to allow more or less coming in.
 

self_sufficient_25

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Self,
When the lvx inverters are in parallel does one inverter sleep and wait for a large load before it wakes up and helps the master inverter? If so what is the watt draw in sleep mode? If not then 280 watts is a fairly large draw. If I did the math in my head correctly thats about 5 amps at 48v. That can't be right I must have done something wrong.
I haven't connected them in parallel yet. So I don't know if one sleeps. Hopefully It doe, But I kind of doubt it.

But you are correct it's around 2.5A at 52v. Each.

That being said when they are connected to the grid the stand by self consumption is supposed to be around 45w, which is quite a bit better. But not useful in my situation.
 
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Rednecktek

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I have 2 lvx6048 inverters. The draw back with them is the stand by current of 140w each, When used of gid.
Also when connected to a generator your power is limited to what the generator can supply.

Other inverters like sunny island and some magnum inverters. Will assist the generator when there is a higher load.

Also if you want to connect the generator to the Lvx6048 it will need to be split phase (240v).

As a alternative, I use a 3500w 120v generator with an external charger. It works well.

Didn't Will do a video on the 5048 predecessor to that one? IIRC he used a jumper wire between the L1 and the L2 inputs to charge it from a 120v inverter from his shed.

I have a similar question though, since I'm eyeballing the 6048 for my camp in the future. If I try to top off the batteries with a generator, will it trip the breaker on the generator or can you set a maximum AC draw limit?
 

self_sufficient_25

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Didn't Will do a video on the 5048 predecessor to that one? IIRC he used a jumper wire between the L1 and the L2 inputs to charge it from a 120v inverter from his shed.

I have a similar question though, since I'm eyeballing the 6048 for my camp in the future. If I try to top off the batteries with a generator, will it trip the breaker on the generator or can you set a maximum AC draw limit?
I can't seem to find the video you're referring to, maybe you could share a link.
What inverter are you referencing?
There is a LV6048, and then a LVX6048 which I have and is totally different from the lv6048.

The Lv6048 can be configured to do 6kw at 120 or 240 and can be used with a 120 or 240 gen.

The Lvx on the other hand is a split phase inverter. And can only be used with a 240 gen.

However bought inverters allow you to set the battery charging amps from the grid/gen. But not the total draw, so when the gen is connected you will be limited to the generator size.

So you can charge your batteries with a small gen, but it's not that practical.
 

beckkl

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Jun 9, 2020
Messages
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I have 2 lvx6048 inverters. The draw back with them is the stand by current of 140w each, When used of gid.
Also when connected to a generator your power is limited to what the generator can supply.

Other inverters like sunny island and some magnum inverters. Will assist the generator when there is a higher load.

Also if you want to connect the generator to the Lvx6048 it will need to be split phase (240v).

As a alternative, I use a 3500w 120v generator with an external charger. It works well.
Can you confirm I cannot use a 120v generator with the LVX6048? Did not realize that and would be a deal breaker
 

self_sufficient_25

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Can you confirm I cannot use a 120v generator with the LVX6048? Did not realize that and would be a deal breaker
Yes I can confirm, 120v gen does not work with the lvx6048.

You would need an external charger or a 120v to 240v transformer for your gen.

But I wouldn't recommend the transformer.
 

offgriddave

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Feb 14, 2020
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I have a lv5048 wired for 240 with a wen 1800w propane generator, split phase noninverter style. I am having issues charging my batteries. I have the utility charge set to 10 amps. When the lv5048 goes to charge mode it pulls 48v 10amps or 480w thereabout. The generator revs up but the lv5048 goes into fault mode. Watching the voltage there is a voltage spike to 148v on one leg for a split second, I saw it by chance. The generator being not an inverter style can't rev up quickly enough to what the lv5048 requires. I used a 700w bench power supply to charge my battery bank but it is a manual process. I thought about preloading the generator with a hair drier but I have not tried it yet. I sent an email to MPP solar asking if there was a way to rwflash the ROM to lower the utility charge from the lowest setting, 10 amps , to something like 1 or 2, and gradually raise it. like a soft start. but there is not an option for this idea

Can I plug my 700w supply into the solar?
Will doing the 120v l1 l2 jumper help? In 120 mode on the generator.

Sorry for the typos on mobile
 
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self_sufficient_25

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Sounds like a small generator. Is it 240v or 120?
If it is 120v it may help to switch the inverter to 120v

Does your power supply have current limiting? And variable voltage?
 

offgriddave

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Yes the power supply is RIDEN RD6018W. The big one, with bluetooth. With a 650w internal power supply kit with box. I set it to 10 amps and 54.4v. I think it was $120 on aliexpress. It stays at 10 amps and when the battery packs get to "54.4v" I can see the watt usage go down and the amps slowly go from 10...9...8.. down to zero. Kind of fun to watch but I'm geek.

I built some special connectors from scrap battery jumper cables 6AWG and gold connectors. Never got hot but I didn't go over 500w.

 
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