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MPP LVX6048 High Temp Throttle?

HouseofSmith

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Mar 12, 2022
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Hey guys. Been lurking for a while but this is my first time posting. Having a hard time tracking down what's going on and was hoping someone had relevant experience they'd be kind enough to share.

I've put together an MPP LVX6048 inverter and built a LiFePo4 battery bank using Solar Overkill cells. I live in Tucson, AZ and have my equipment is mounted in my garage. Unfortunately, it gets ridiculously hot in there (poor insulation on top of high desert temps.) I anticipated the heat would have a strong effect on the batteries, so I repurposed my chest freezer I used for homebrewing beer and an Inkbird controller to maintain a 70-degree environment for the batteries, the BMS, and the Raspberry Pi running Solar Assistant for monitoring. I'm powering the system with 10 Canadian Solar 390W bifacial panels in a 2P5S configuration.

The problem is the inverter seems to be significantly throttling power when the inverter's internal temp exceeds 55 degrees Celsius. Solar Assistant shows that as high temp threshold. When it gets that hot, the current drops and will only pull a few hundred watts from the panels.

I attempted to correct by relocated the inverter into the chest freezer. When I turn everything on and it's cold, it will max out the batteries at a 40-amp recharge rate, pulling a little over 2kW. Problem is the inverter is putting out heat faster than the chest freezer can remove it. On my last attempt, I shut everything down when the inverter hit 59-degrees Celsius (136.4 F) and power started dropping off.

Is this expected? I can't seem to find anything in the manual to explain this. Only thing I see is the over-temp fault that should happen if the inverter's internal temp exceeds 100-degree Celsius (which I have not had happen.)

Worth mentioning... the chest freezer is small so the only way I can fit the inverter in there is to lay it on its back. There's not enough room to maintain the manufacturer's 50cm of space on each side of the inverter (where the vents are). That said, I don't think this is an issue of poor air flow through the inverter case since even the Inkbird is registering 100+ degrees.

If it's operating as expected, the only thing I've been able to come up with is to build a very small closet around the equipment, insulate, and run a high efficiency window unit (without the window) that can extract heat at a much faster rate than the chest freezer. I'm not particularly excited for this to be the answer and hoping someone can nudge me in a smarter direction.
 
Welcome to the party.
How about a small fan or 2 pointed at the inverter in your freezer. Sounds like something is going to melt soon.
 
Hey guys. Been lurking for a while but this is my first time posting. Having a hard time tracking down what's going on and was hoping someone had relevant experience they'd be kind enough to share.

I've put together an MPP LVX6048 inverter and built a LiFePo4 battery bank using Solar Overkill cells. I live in Tucson, AZ and have my equipment is mounted in my garage. Unfortunately, it gets ridiculously hot in there (poor insulation on top of high desert temps.) I anticipated the heat would have a strong effect on the batteries, so I repurposed my chest freezer I used for homebrewing beer and an Inkbird controller to maintain a 70-degree environment for the batteries, the BMS, and the Raspberry Pi running Solar Assistant for monitoring. I'm powering the system with 10 Canadian Solar 390W bifacial panels in a 2P5S configuration.

The problem is the inverter seems to be significantly throttling power when the inverter's internal temp exceeds 55 degrees Celsius. Solar Assistant shows that as high temp threshold. When it gets that hot, the current drops and will only pull a few hundred watts from the panels.

I attempted to correct by relocated the inverter into the chest freezer. When I turn everything on and it's cold, it will max out the batteries at a 40-amp recharge rate, pulling a little over 2kW. Problem is the inverter is putting out heat faster than the chest freezer can remove it. On my last attempt, I shut everything down when the inverter hit 59-degrees Celsius (136.4 F) and power started dropping off.

Is this expected? I can't seem to find anything in the manual to explain this. Only thing I see is the over-temp fault that should happen if the inverter's internal temp exceeds 100-degree Celsius (which I have not had happen.)

Worth mentioning... the chest freezer is small so the only way I can fit the inverter in there is to lay it on its back. There's not enough room to maintain the manufacturer's 50cm of space on each side of the inverter (where the vents are). That said, I don't think this is an issue of poor air flow through the inverter case since even the Inkbird is registering 100+ degrees.

If it's operating as expected, the only thing I've been able to come up with is to build a very small closet around the equipment, insulate, and run a high efficiency window unit (without the window) that can extract heat at a much faster rate than the chest freezer. I'm not particularly excited for this to be the answer and hoping someone can nudge me in a smarter direction.
Just started exploring threads for a similar lesser challenge; noticing how my back room w 21 Kwh worth of LiFePO4s and four MPP LV2424 Heats Up on my hotter summer 95 -100 F days. While I am not having your "inverter throttling power" issues, ... I am thinking of moving a small 5000 BTU AC unit I have, that might pull 4 amps 120vac, to my battery inverter back room, and setting the thermostat (or possibly using a timer) to power up AC mode for just those hot afternoon cycles. I have two 12000 BTU Heat Pumps I like much better for cooling or heating my main house; but a small 4 amp 120 AC unit might cost less than $200. I think that idea would work best for a closet with and air flow exit vent. Here's an energy efficient model: https://www.amazon.com/Keystone-Ene...efix=Keystone+KSTAW05C,garden,156&sr=1-1&th=1

... Food for Thoughts on Options, ... especially since it seems you'd have plenty PV power for a 4 or 5 amps AC when your inverter is not throttled (if that is the indeed what is going on). ... Another Options for How Questions. ... I once cooled down a storage shed that had a slanted plywood w roll roofing roof; ... by stapling some 4 foot wide reflective bubble wrap to the underside of the roof rafters. That made an air space to isolate my roof heat. ... and with venting on downside and upper side of roof, most of the hot air was vented to high side. That idea might make a difference too.
 
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I'm in Az too but with 6500/48 inverters. Mine shut down with an error the first time inn a mid day sunny peak. Air coming out was 120F. I used an infrared temp gun. I removed the bottom access covers and filters/grills on the top. It dropped the outlet temps 10-15 degrees. Then I added a small fan blowing against them to move the hot air further away after it exits. I now just leave the evap cooler on in the garage plus the small fan. It keeps everything under 90F including batteries.
 
I removed the bottom access covers and filters/grills on the top. It dropped the outlet temps 10-15 degrees.
Wow to dropping 10-15 degrees ! ... That's a good trick (removing bottom access covers and top filters) ... to know about. ... I noticed the increased air flow when my LV2424 bottom covers were removed, but left them on with my slight concern of bugs more easily moving in to all in ones. If I had shut down issues; I would certainly take in off my bottom covers, plus possibly experiment with silicon glue and a bug screen covering if I still had bug concerns. Sounds like you got a good handle on your past issue. Great Ideas and News.
 
My water heater is in the garage. I had the same problem with high heat, but it went away when I replaced a standard electric water heater for a heat pump water heater. It's basically an air-conditioner for your garage.

(which btw, the new Biden climate bill gives a $1750 rebate on heat pump water heaters, so its nearly free depending on your income)
 
My water heater is in the garage. I had the same problem with high heat, but it went away when I replaced a standard electric water heater for a heat pump water heater. It's basically an air-conditioner for your garage.

(which btw, the new Biden climate bill gives a $1750 rebate on heat pump water heaters, so its nearly free depending on your income)
I have been eyeing those Heat Pump HWT units too! if they work as claimed, they use only 20% of the power of normal elect HWT which would put this load into the range I could power with my solar...and side benefit get the cooling 'for free' kinda. I was looking at the 50Gal Rheem from Home Depot, what unit did you use? did it really save this much power?
 
I also live in Tucson AZ and have a pair of the LVX 6048s. I have been keeping an eye on the temps in the garage where they are located. I have a shop fan that the wife turns on around lunch time for a couple hours on hot days. The only real issues I have seen is an occasional drop of all power in the house but comes back in 5 seconds. To long to not kick of things like computers. I think it is related to heat, as I have worked out the other issues related to error code 80 and high and low settings on batt charging. I had to keep them under the seplos bms settings. I dont have have solar assistant nor the wifi setup for the inverters yet. That is my next hurdle. Temps in the garage are usually 100 to 110 when it is hot and I suppose internal inverter temps pretty close to that 50 c threshold. I cant wait for cooler weather.. Those inverter fans really get going, one of them always more so. Anyway, you are not alone in this heat battle.
 
I also live in Tucson AZ and have a pair of the LVX 6048s. I have been keeping an eye on the temps in the garage where they are located...Those inverter fans really get going, one of them always more so. Anyway, you are not alone in this heat battle.
Consider what you can do to keep the sun from heating the garage. 20 years ago when my wife and I bought our homestead, the shop needed new siding/roofing so we picked a light beige metal for the walls and galvalume for the roofing, we added insulation to the walls and attic while we were at it. Bang, the shop was transformed 20-degrees cooler in summer just from reflecting more of the sun's heat. My house is 100 feet from my shop, but the shop is always much cooler (with no A/C at all) all summer just due to the difference in how much heat gain the house has with dark asphalt shingles, large windows, and regular wood siding, compared with the work shop. Yesterday it was 29C (84F) outside, but inside the workshop only got up to 21C (70F) all day, meanwhile yeah the house was too hot and we put the A/C on. Something to consider in addition to the heat-pump HWT.
 
Consider what you can do to keep the sun from heating the garage. 20 years ago when my wife and I bought our homestead, the shop needed new siding/roofing so we picked a light beige metal for the walls and galvalume for the roofing, we added insulation to the walls and attic while we were at it. Bang, the shop was transformed 20-degrees cooler in summer just from reflecting more of the sun's heat. My house is 100 feet from my shop, but the shop is always much cooler (with no A/C at all) all summer just due to the difference in how much heat gain the house has with dark asphalt shingles, large windows, and regular wood siding, compared with the work shop. Yesterday it was 29C (84F) outside, but inside the workshop only got up to 21C (70F) all day, meanwhile yeah the house was too hot and we put the A/C on. Something to consider in addition to the heat-pump HWT.
I like the heat pump water heater idea and have started reading up on them and the rebates that start 1 Jan 23. I plan on extra insulation over the winter in the attic especially over the garage. I live in a subdivision with an HOA, my options are limited for shading the roof.. maybe more panels over the garage lol that would work. Thanks for the tips.
 
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