I think my MPP LV2424 may be defective - Help needed

[FoundationsEdge]

I purchased the Complete Off-Grid Solar Kit - MPP LV2424 2,400W/120V / 24VDC [2.56Kwh - 4.8Kwh Battery Bank] + 800 Watts Solar | Off-Grid, Mobile, Backup [HBK-2] × 1.

I am extremely frustrated with this system as Shop Solar kits support has been extremely slow to help me and unable to really explain to me what the issues are. I am wondering if anyone can help me understand what settings are best for a solar application only. I did install a plug to provide AC as a backup source for charging the batteries but that was only as a backup. The desired use is solar only. In addition, whether I have AC connected as a backup source for charging or not I run into the same problem. I will provide my logs. The core issues. The batteries in the unit are constantly being run down to the point where the alarms trigger and will eventually drain to the point where the inverter shuts down. I've been through a number of different troubleshooting scenarios, and they all end the same. To keep it simple. I reduced my load down to a thermoelectric humidor and my inverter itself. (Normally I am trying to run about 600 watts of supported load). in the attached logs;

Starting on 6/24 at 17:48 the batteries are at 100% capacity. PV in is at 182 watts. I'm using about 36 Watts of power.

By 6/24 at 18:19 PV in is at 34.8 and I'm using 24 watts. But by this point battery capacity has dropped to 68%

At 18:47 I remove my test load which was a small thermo-electric humidor. The only load at this point is the inverter itself. 12 watts of consumption. with 48.3 PV IN.

At 20:40 I shut the system down out of frustration because of all the alarms and clicking. The battery was at 56% capacity.

Does it make sense that the battery is used SO FAST with such a small load of 12-24 watts? The batteries I am using are 2 Renogy Deep Cycle AGM Battery 12-Volt 200Ah. At 12 volts 200 Ah, that should be 2400 watt hours. Assuming my maximum wattage out was a consistent 36 watts 2400 / 36 = 66.66 hours of battery. Yet the batteries went from 100% capacity to 56% capacity (according to WatchPower) in just 3 hours I used somehow 1200 watt hours? I'm thoroughly confused.

It just seems like the system is operating incorrectly. It seems to me like the batteries are not charging when / how they should be, and are draining way too fast. I have no idea where to start on this and the support over at Shop Solar kits has been really bad. This same thing happens if I have my AC charging from house current available as well. The same thing happened with the batteries they shipped me which were LifePO4 1280 watt hour batteries. I figured with the house current there is no way the system should hit the point of alarming over a low battery and clicking at me as it loudly changes modes. But again I don't want to rely on house current for this (I desire PV only)... More information that may be helpful. Logs are attached. batteries are connected in series to provide the required 24 volts to start the inverter. 4 Solar panels are connected in series as well. Is this normal behavior? What settings are recommended in the Inverter for Solar only? Very appreciative of any help here. For the money I spent on this system, I sincerely hope I am doing something wrong on my end or it is a defective inverter or something. As it is right now, this system appears useless to me when the sun goes down. If you look further back in the logs you will see where the batteries dip as low as 38%, and at that time you will also see that I had the house current connected in to help things out. That just "seems" wrong. When the system goes from line mode to battery mode (why?) the batteries go from 100% to 84% in 1 minute to 66% to 52 and then 46 in 4 minutes. And very little charging. Okay, enough ranting. I'm hoping someone can help me figure out how to look at this one.

 

[12VoltInstalls]

Do you have the manual ?

s this normal behavior?

No

What settings are recommended in the Inverter for Solar only?

SBU Solar/Battery/Utility

Does it make sense that the battery is used SO FAST with such a small load of 12-24 watts?

Someone please correct me but the standby consumption is ~120W? So ~150W total 6A constant at 24V

First, 800W of solar is what I run with walmartha flooded ~100Ah batteries. 8 of them.
An optimist that understands lead batteries would say that’s 400Ah of usable storage. A realist (me) says that’s ~300Ah+ and is barely a day/overnight of storage for my usage. I didn’t go for two or three days because long, dragged-out periods of discharge with commodity lead batteries don’t work out and if I hurt the batteries I wanted to minimize my loss.
So my point is you have nothing for batteries. The 6A draw will flatten them faster than the math says.

24VDC [2.56Kwh - 4.8Kwh Battery Bank]

Your lead batteries were 200Ah at 24V usable. You’re cramped for storage with the idle consumption

What condition was the sunlight when you were making 65-100W?

First you need to figure out why your solar input is low other than not enough panels. Are they positioned correctly?

 

[Prince Of Darkness]

I know nothing of the LV 2424 ...

But there are a couple short videos on youtube one from Will Prowse, and another by Lithium Solar. I would post a Link, but that may not be permitted -- am neiw here.

One review noted that the idle power of the 2424, was about 53 watts.

Looked, briefly, at the OP's data. It looks like there is essentially NO charging of the batts. The time seemed to be about 6:20, (PM, IIRC). There may be shade/heavy shade at that time, perhaps. Any shading really kills PV production.

It is quite likely, that there are some settings that need to be changed, or, perhaps, some wiring issues.

What are the specs on the PVs, and, how are your PVs configured?

Little time now, but Good Luck, Vic

 

[acdoctor]

So you are a bit all over the place and it’s a little hard to tell exactly what you have. With all the +. - brackets and the like. Also batteries may be LFP or AGM or both. My suggestion is to study the specific battery documents for bulk, absorption and float value . Then become familiar with the inverter settings and input the battery recommend values to start. This will insure the battery is getting charged properly.
Also AGM is fancy lead acid. The usable AH is about half of the name plate Ah. If you discharge total AH about 20 times you can throw them away.
Remember you need to fully recharge the batteries during the sun up hours and support load at the same time. If you are producing 600 watts and consuming 550 watts you aren’t charging batteries.
Also battery monitor has to be calibrated to the batteries.
Solar requires learning all of your equipment and how they interact. I think you are incorrect on the idle consumption as well. My 3000W growatt is about 65 watts. 65wattsx24hours= 1560 watt hours.
Ideally aligned panels is 800watts solar x 5 hours =4000 watt hours.
4000w - 1560w = 2440w / 24 volts = 101AH usable capacity.

 

[FoundationsEdge]

Do you have the manual ?


No

SBU Solar/Battery/Utility

Someone please correct me but the standby consumption is ~120W? So ~150W total 6A constant at 24V

First, 800W of solar is what I run with walmartha flooded ~100Ah batteries. 8 of them.
An optimist that understands lead batteries would say that’s 400Ah of usable storage. A realist (me) says that’s ~300Ah+ and is barely a day/overnight of storage for my usage. I didn’t go for two or three days because long, dragged-out periods of discharge with commodity lead batteries don’t work out and if I hurt the batteries I wanted to minimize my loss.
So my point is you have nothing for batteries. The 6A draw will flatten them faster than the math says.

Your lead batteries were 200Ah at 24V usable. You’re cramped for storage with the idle consumption

What condition was the sunlight when you were making 65-100W?

First you need to figure out why your solar input is low other than not enough panels. Are they positioned correctly?

First of all thanks for the reply. I was afraid of this. The light has been good during the day. The solar input was low (the installer said) because the panels are connected in series vs in parallel. The installer wanted to connect them in parallel but the company via a support call recommended to connect them in series. I'm no electrician, so the math you are using goes over my head unless I really noodle it more. If these two batteries can't run a small thermo electric humidor for more than a few hours solar isn't for me. That's my takeaway. Even if I were to get more solar pumping in, the issue seems to be I expect more from the batteries than they realistically are capable of. I chalk this one up to not doing the research and taking someone's recommendation. Of course I was told this system would be plenty for a small shed solar solution.

So let me ask the question in a way I might understand it. How much battery would be required to sustain 500 watts for a 12 hour period since manufacturers guidelines can't be used....

 

[FoundationsEdge]

I know nothing of the LV 2424 ...

But there are a couple short videos on youtube one from Will Prowse, and another by Lithium Solar. I would post a Link, but that may not be permitted -- am neiw here.

One review noted that the idle power of the 2424, was about 53 watts.

Looked, briefly, at the OP's data. It looks like there is essentially NO charging of the batts. The time seemed to be about 6:20, (PM, IIRC). There may be shade/heavy shade at that time, perhaps. Any shading really kills PV production.

It is quite likely, that there are some settings that need to be changed, or, perhaps, some wiring issues.

What are the specs on the PVs, and, how are your PVs configured?

Little time now, but Good Luck, Vic

4 x 200 Watt Monocrystalline Solar Panels 12V - 25-Year Power Output Warranty connected in series.

They get good sun no shade for about 5 hours. If they were connected in parallel I would get more from them.

Also there is the information I added about having AC also being available to feed the battery charging (not just solar although that is my desired configuration). I seems like I'm expecting too much from this system...

 

[FoundationsEdge]

So you are a bit all over the place and it’s a little hard to tell exactly what you have. With all the +. - brackets and the like. Also batteries may be LFP or AGM or both. My suggestion is to study the specific battery documents for bulk, absorption and float value . Then become familiar with the inverter settings and input the battery recommend values to start. This will insure the battery is getting charged properly.
Also AGM is fancy lead acid. The usable AH is about half of the name plate Ah. If you discharge total AH about 20 times you can throw them away.
Remember you need to fully recharge the batteries during the sun up hours and support load at the same time. If you are producing 600 watts and consuming 550 watts you aren’t charging batteries.
Also battery monitor has to be calibrated to the batteries.
Solar requires learning all of your equipment and how they interact. I think you are incorrect on the idle consumption as well. My 3000W growatt is about 65 watts. 65wattsx24hours= 1560 watt hours.
Ideally aligned panels is 800watts solar x 5 hours =4000 watt hours.
4000w - 1560w = 2440w / 24 volts = 101AH usable capacity.

If you are producing 600 watts and consuming 550 watts you aren’t charging batteries.

This makes sense. It is what I am seeing. Just like the literature out there people bounce between amp hours and watt hours, and it makes it difficult to realistically know what to expect from batteries. My main question was about the batteries draining so fast. Yes it likely got buried in the info I was posting. I don't know what else to post on the batteries. They are 12V 200Ah/20HR valve regulated sealed lead acid batteries.

Assuming a 500 watt load, how long would you expect these to last without damaging them?

 

[cotrailhead]

I run the lv2424 and can help but you’re going to have to be willing to work through some questions that are fundamental to the questions that you are asking. I’m going to ask one at a time because I don’t have the patience to search back through long confusing threads. I believe you mentioned that you have 4 12 volt 200 watt solar panels wired in series. This needs to be confirmed. If you can, take a picture of the data printed on the back of the panel and post it. If you can’t take a picture, we need to know two things. Specifically I’d like to know the volts open circuit (voc) and the short circuit current OR the max power current

 

[cotrailhead]

So I think I found your kit on shop solar. I would still like you to confirm the voltage and current of the panels ( or a picture) if possible but I do see where the stats are provided on the webpage. If those stats are accurate, then you did the right thing by wiring the panels in series. If they were wired in parallel they would not create the voltage necessary for the lv2424 to do any charging. It would be very nice to confirm they are in fact wired in series. The positive from one panel should be connected to the negative of the next panel. An easy way to confirm this is by looking at your lv2424 display. When the sun is directly on your panels, use the up or down arrow until you see where the input voltage is displayed. Report back with that number and we can move on to next steps.

 

[cotrailhead]

500 watts for 12 hours is 6kw. Your lifepo4 battery at most has about 2.4 kw. Your 2 agms are also about 2.4 kw usable storage. With eithe the agms or the lifepo4 your at less than half the capacity to run 500 watts for 12 hours.

 

[12VoltInstalls]

The solar input was low (the installer said) because the panels are connected in series vs in parallel.

Hogwash. An idiot

you did the right thing by wiring the panels in series.

Follow his instructions that say to measure VOC of the string. Like I said, the first thing is to figure out is the very low solar input. 800W still isn’t enough panels imho but you aren’t getting anything near what I’d expect from them.

 

[acdoctor]

If you are producing 600 watts and consuming 550 watts you aren’t charging batteries.

This makes sense. It is what I am seeing. Just like the literature out there people bounce between amp hours and watt hours, and it makes it difficult to realistically know what to expect from batteries. My main question was about the batteries draining so fast. Yes it likely got buried in the info I was posting. I don't know what else to post on the batteries. They are 12V 200Ah/20HR valve regulated sealed lead acid batteries.

Assuming a 500 watt load, how long would you expect these to last without damaging them?

If you have 2 of the above mentioned batteries “12V 200Ah/20HR” in series.
2 12 volt batteries in series is 24 volts and the AH stay the same 24V 200AH.
The “ /20HR “ means if they are slowly and evenly discharged over 20 hours.
The usable portion is 200 AH so 200AH / 20hours = 10amps
If you demand a higher discharge from the batteries the AH capacity changes to a smaller number. This is not a linear thing though.
If you demand 20amps continuous doesn’t reduce the capacity to 50AH usable its somewhat worse than that. There should be a publication available for your specific battery that shows capacity at different discharge rates.
The chemical reaction in deep cycle batteries is slow. You should not plan to discharge them faster than the 20 hour rate.
All of that said
Your battery capability 10amps x 24volts = 240watts
Your requirement. 20.8amps x 24volts = 500watts
You have about half of the battery needed for the load you want to run without calculating your inverter losses. Which I think is about 50 watts.
That 50 watts is coming from somewhere the entire time the inverter is on. Either from panels or batteries.
Your requirement. 20.8amps x 24volts = 500watts + 50watts = 550watts.
550watts / 24volts = 23amps x 20 hours = 460AH
460AH at 24volts would be the correct size battery.
That is the correct way is to calculate the load then the battery requirements then the panel requirement to recharge the battery while carrying the load.

 

[FoundationsEdge]

So I think I found your kit on shop solar. I would still like you to confirm the voltage and current of the panels ( or a picture) if possible but I do see where the stats are provided on the webpage. If those stats are accurate, then you did the right thing by wiring the panels in series. If they were wired in parallel they would not create the voltage necessary for the lv2424 to do any charging. It would be very nice to confirm they are in fact wired in series. The positive from one panel should be connected to the negative of the next panel. An easy way to confirm this is by looking at your lv2424 display. When the sun is directly on your panels, use the up or down arrow until you see where the input voltage is displayed. Report back with that number and we can move on to next steps.

Yes those stats are accurate. I no longer have access to the panels as they are installed on the roof. Going to my order number, and looking up the exact system. I can confirm they are wired in series. I brought the adapters for the installer to connect in parallel and they have NOT been installed yet. So I am certain they are in series. Physically I know that they are connected as you say the positive of one panel connected to the negative of the next in the line.

Maximum Power(Pmax)	200W
Maximum Power Voltage(Vmp)	20.4V
Maximum Power Current(Imp)	9.80A
Open Circuit Voltage(Voc)	24.3V
Short Circuit Current(Isc)	10.2A
Maximum System Voltage(Vmax)	1000VDC
Temperature Range	-40°C ~ 90°C
Dimensions	58.7 x 26.8 x 1.4 in
Weight	26.5 lbs
Warranty	25 Years

Please let me know if I haven't answered any of your questions. The system isn't on right now but I can go ahead and fire it up to get more.

 

[cotrailhead]

Good deal. Now. When I’m looking at my lv2424 display and I hit the down button 2-3 times it displays the input voltage on the left side of the display. When your solar panels are getting good sun, I would like to know what your input voltage is.

 

[zack6736]

I too have the MPP Solar LV2424, 10-200 watt panels and two LiFePSO4 200AH batteries, also purchased from shop solar kits. I am experiencing the same issues. I'm a newbie and in over my head at this point. Since I installed and fired up my system I've been having to run it in bypass mode in order to keep my pond going, so basically just pissed away $5400 at this point. Support???? HA HA Ha!! I'll be watching this post closely!

 

[FoundationsEdge]

I really appreciate all the help and expertise here in this forum. SINCERELY. Unfortunately, I've given up my quest for a solar solution and decided to return the system. For what I'm looking to do it just isn't economical. For an off-grid solution, the industry really needs to stop the drivel and be up front with people on sizing and pre-planning on the batteries and subsequent loads. Just tell people realistic usage for given loads of their batteries and it would save people a lot of trouble. In retrospect it all makes sense. I have a nice UPS for my computer. Powers it for about 15 minutes in a power outage. Gives me time to shut it down properly. The manual tells me this. It isn't meant to sustain your power but to allow you to react. If these systems are meant to power real world workloads for 10-12 hours at a time when the sun goes down, just tell people, you'll need a lot of really big batteries. Can the "casual usage" terminology and give the data people need.

 

[zack6736]

I too am new to solar. I have found my batteries may not do what I expected as well. I have two 200AH LiFePo4 in series. I got alot of bugs ironed out on my LV2424 yesterday. I still need to tweek the settings. I'm sorry you're giving up on solar, I have come to realize it's an expensive hobby. I bought it to power my 10,000 gallon koi pond which has two pumps, two UV lights, two air pumps and a 1050 watt 10amp waste water pump to keep the pump pit from flooding and move my waste water out to my plants. The solar has become part of the 'hobby'.

 

[labeeman]

I have a system that I DIYed it has so far 25KW of battery and 7KW of solar, 800 watts is too little for anything over a couple of hundred watts as you can only expect 80% of your solar times 5 on good days.

 

[FoundationsEdge]

I too am new to solar. I have found my batteries may not do what I expected as well. I have two 200AH LiFePo4 in series. I got alot of bugs ironed out on my LV2424 yesterday. I still need to tweek the settings. I'm sorry you're giving up on solar, I have come to realize it's an expensive hobby. I bought it to power my 10,000 gallon koi pond which has two pumps, two UV lights, two air pumps and a 1050 watt 10amp waste water pump to keep the pump pit from flooding and move my waste water out to my plants. The solar has become part of the 'hobby'.

Out of curiosity... right now when the sun goes down, how long does that system stay running on those two batteries?

 

[zack6736]

I was pulling right at 550 watts, unplugged from utility and forced the inverter to use the batteries, it ran for 10-11 hours, then the batteries were drained to the point I had to charge each one up so I could power the LV2424 back on. It was part of my learning process. I really expected the batteries to last longer than that. I do not want that happening again, so need to change the settings on the inverter but I need to post a new post listing current conditions and ask for recommendations.