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MPP-Solar LVX-6048

Hi,

What will be the best way to install a rapid shutdown switch and how for the LVX 6048, my system in on the grid, I have a DC disconector for solar pv.

Thanks
 
Hi,

What will be the best way to install a rapid shutdown switch and how for the LVX 6048, my system in on the grid, I have a DC disconector for solar pv.

Thanks
I use a knife switch to change between Grid and Inverter to the panel, and a breaker from the main that feeds my inverters.
 
I'm running 3 LVX6048 in parallel and they get quite hot.
Hello, mine get got also up to 61C but my lv5048 just hit 43C max, seem like the lvx6048 just have 1 speed on their 2 built in fans while the lv5048 have variable speed on their 4 built in fans
 
Hello, mine get got also up to 61C but my lv5048 just hit 43C max, seem like the lvx6048 just have 1 speed on their 2 built in fans while the lv5048 have variable speed on their 4 built in fans
Hmmm. That makes me wonder how the new LVX6048WP's will cool themselves. SMA talkes about their fancy"opticool" cooling abilities for their enclosed sunny boy inverters. I am hopeful the WP's will have something similar, as they are also fully enclosed with no external fans.
 
Hello, mine get got also up to 61C but my lv5048 just hit 43C max, seem like the lvx6048 just have 1 speed on their 2 built in fans while the lv5048 have variable speed on their 4 built in fans
The fan speed of my LVX6048s is regulated gradually, depending on the load or temperature. I think that the higher heating of the LVX6048 compared to the LV5048 is due to the built-in copper / iron transformers.
 
Has anyone overpaneled this unit yet? I am considering it based on what I read, it appears that it can be overpaneled
but that the VOC needs to be under the max. My Lvx6048 should be here thursday :)
I thought I read that someone had a clipping issue but that it was a different unit.
 
I've overpanneled my LV6548. Not the same, but similar. It will just clip at max Current. I put 23a through mine and it clips at 17.5a. No damage.
 
The specs on the LVX6048 manual I downloaded from watts says PV input max 450 Voc and 27 amps.
Multiplying them gives over 12k watts. That was curious to me. I was not expecting to see something like that,
but then I am new to this particular game. I would never hook up that much power. Some of the Australian vidoes
suggest no more than 30% overpanel. I think I read in our forum no more than 15%.
Thank you for the replies!
 
The specs on the LVX6048 manual I downloaded from watts says PV input max 450 Voc and 27 amps.
Multiplying them gives over 12k watts. That was curious to me. I was not expecting to see something like that,
but then I am new to this particular game. I would never hook up that much power. Some of the Australian vidoes
suggest no more than 30% overpanel. I think I read in our forum no more than 15%.
Thank you for the replies!
My LV2424 is similar. 150vdc max and 80a max which is also 12k watts, but it is limited to 2000w of PV input. I wouldn't over panel by much more than 15% either, but if you are going to over panel, due it on the amperage side and most importantly make sure you have plenty of cushion on the voltage side. I am running 2250w and the preferred voltage range is 30-115vdc. I typically see 105vdc max out of 3P3S, and the biggest output I have seen is about 1700w so far. So, in theory I am not over paneled at all, except maybe in a laboratory under perfect conditions.
 
Well I live in a household of 12 people so 400 gallons isn't really that much.
Yes the plan would be to super insolate and have a coil at the top that heats the domestic water. So the tank doesn't need to be food grade.

I have worked with solar flat plat and vacuum tube panels. Both work but have there disadvantages you need to use a glycol or drain back system so they don't freeze. If you lose power to the pumps they will over heat and blow off glycol, and than get air locks and a host of other problems.

Maybe a good design would remedy those issues.

But although PV is less efficient but in my opinion simpler and more cost effective.
Use an expansion tank like a boiler uses......
 
The specs on the LVX6048 manual I downloaded from watts says PV input max 450 Voc and 27 amps.
Multiplying them gives over 12k watts. That was curious to me. I was not expecting to see something like that,
but then I am new to this particular game. I would never hook up that much power. Some of the Australian vidoes
suggest no more than 30% overpanel. I think I read in our forum no more than 15%.
Thank you for the replies!
No, it is rated for 6Kw PV input. https://www.mppsolar.com/v3/catalogs/LVX6048.pdf

That is max. I don't recommend overpaneling it either. If you look at kromc5 and his build, he fried a different model but the rules still apply. Many will think the SCC will clip the PV input. It all depends on the load. If you run high PV input voltage, then amps need to be lower to keep the input at 6Kw.

I touched on the subject here: https://diysolarforum.com/threads/d...grid-backup-neutral-bonding.29717/post-398720

My recommendation is input the rated Max PV Kw, add additional SCC's for more PV input.
 
Use an expansion tank like a boiler uses......
The glycol system defantly has a expansion tank, as it is a closed system.
But it won't make up for steam expansion. If that's what you're referring to.
 
What? Steam expansion? In a closed loop system hot water or glycol that should never be allowed to boil? The expansion tank is designed to accommodate the increase in pressure created when the fluid temp rises. Do you have adequate expansion capacity? Was the tank sized properly for the tank?

I have an 80 gallon heat exchange tank, and our expansion tank is 36" high, and about 16" diameter. I don't like working with glycol if at all possible to avoid it. I do drain back only, due to cold climate.
 
The glycol system defantly has a expansion tank, as it is a closed system.
But it won't make up for steam expansion. If that's what you're referring to.
If the tank is big enough, it should work. The tank should be sized according to total volume of the system including piping.

If you are seeing boiling occur, then either the collector is too large for the system or you aren't moving the glycol thru the system or fast enough. The boil can occur if power fails but battery backup can fix that plus drain back. If the pump is undersized, then the glycol won't move fast enough.

I think many put up a very large oversized collector with the thought they can supply more hot water than they can use, but don't install large enough holding tanks and pumps. There is a balance that needs to be achieved.
 
Yes.
It would only blow off steam when the power was out.
And yes it is important to have a dump zone. To keep the panels from overheating. And a hole host of other things required to make a system safe and reliable, pressure relief valves, air bleads, proper sized pump('s), expansion tank, and heat exchanger.
And of course a controller to operate the pump('s),
A back up power supply may help.

Or in my case just a more reliable off grid setup.

My earlier point was, yes thermo panels work.
But Pv may be more cost effective and less trouble.
 
Yes.
It would only blow off steam when the power was out.
And yes it is important to have a dump zone. To keep the panels from overheating. And a hole host of other things required to make a system safe and reliable, pressure relief valves, air bleads, proper sized pump('s), expansion tank, and heat exchanger.
And of course a controller to operate the pump('s),
A back up power supply may help.

Or in my case just a more reliable off grid setup.

My earlier point was, yes thermo panels work.
But Pv may be more cost effective and less trouble.
Yikes! I agree with Zwy, it is likely you are not moving enough fluid. Are the panels stagnating? I had seriously considered going with closed loop, because I have a lot of experience (professionally) with pumping technology. But decided it just wasn't worth the risk. Also, we have had hellacious hail storms here, and I don't trust evacuated tubes to survive 1" hail.

You need a good controller hooked to a variable speed pump, a good sized storage tank, and big enough expansion tank. I have a really interesting Tekmar injection pumping controller sitting on the shelf, have always wondered if it could be utilized to control flow through a sealed plate system.

I do agree with you on the conclusion...it is probably simpler and more reliable to go with PV.
 
Yikes! I agree with Zwy, it is likely you are not moving enough fluid. Are the panels stagnating? I had seriously considered going with closed loop, because I have a lot of experience (professionally) with pumping technology. But decided it just wasn't worth the risk. Also, we have had hellacious hail storms here, and I don't trust evacuated tubes to survive 1" hail.

You need a good controller hooked to a variable speed pump, a good sized storage tank, and big enough expansion tank. I have a really interesting Tekmar injection pumping controller sitting on the shelf, have always wondered if it could be utilized to control flow through a sealed plate system.

I do agree with you on the conclusion...it is probably simpler and more reliable to go with PV.
Yes like I said it was a problem when the power was out.
 
Yes like I said it was a problem when the power was out.
I ran across this video last night and thought, hey, that expansion tank design with an overflow would be perfect.

Pressure cap release pressure should be slightly lower than the pressure relief valve on the system. Overflow would contain excess and pull it back into the system as system cooled down. The radiator type expansion tank would need to be mounted low to prevent steam from reaching it and venting glycol steam to atmosphere.

This would be a better system than one that uses a boiler type expansion tank with a bladder.
 
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