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Growatt 24V SPF 3000TL LVM off-grid

Yea, I believe the recommendation is #2 AWG for the 24V 3000. Using the right cable size, and tight connections is super critical for these inverters.
 
Yea, I believe the recommendation is #2 AWG for the 24V 3000. Using the right cable size, and tight connections is super critical for these inverters.
It is. (or 2x 6 awg) regardless It's a good answer and more to the point put me back on track. I was simply overzealously testing my new toy :) The intended use is in the RV since I was planning a 2200ish watt max and bought enough battery for that ... so the battery is 100a max continuous it's an impossible test, wiring aside, if the shop vac is pulling anything over 2400 ( it clearly is ) the BMS will cut it off anyway. So I am getting the correct response from the inverter. I am not really interested in investing more $$ in battery + cabling since my 2000 watt gen set does just fine but we were looking for some QUIET power, boondock use, and some solar/inverter practice for doing the house -- it looks like it will have no problems with that.
 
I haven't put my 24V 3k through anything very difficult yet. Over all I am quite pleased with it. It runs the 5k BTU window unit in the solar shed without issue. That's probably the largest surge load I have put on it. When Hurricane Ida came through it ran the full size fridge just fine. I didn't see the compressor running much but it was drawing about 500watts the same as the window unit.

Quite happy with it for the cost. The only downside so far is that high idle on the inverter. When the inverter is off and the MPPT controller is still on I have noticed that it draws between 10 and 20 watts until it gives up and says the sun is down. And then we see the 2 watts advertised idle draw. I am running the ShineWIFI-S USB dongle for monitoring. Sure there's a little power draw there as well.

Joe-
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I'm really enjoying my 24v 3000tl unit as well, and yes I'm using it completely off-grid.

I've seen surges of almost 5000 watts using my mitre saw, and the documentation claims to support surges up to 6000 watts.

Soooo quiet.. such a nice upgrade from my 12v Magnum inverter (ie the buzzer!!)
 
A good first tryout for me camping at a no utility site over the weekend. the EPG4 24v 200AmpHr battery did well , Hooked up to a Victron 70amp 24->12 converter and the 24V 3000 inverter. I did a 2 solar panel test in series 70-80v and pulled a peak of 640 watts and was happy with that. It also ran an electric heater at 600 watts all night and pulled the battery down to 26% , I set the charging amps to 50 and used my igen 2500 @ 1500 watts letting the small tank run to empty left the battery at 96%, about 3.5 hours - nice. My trailer had a known bad charging unit so no more killing 12v batteries all the time - yeah! and the kill switch is built right into the battery I disconnected the older trailers 120->12v supply completely .
 
The story is coming to an end. I switched from Growatt to VE and I am happy. For those interested:


I loved the Growatt system, but could not resolve the power fluctuations and the flickering. The VE system runs flawlessly. I want to install another small stand alone system to handle my furnace and blower. I really hope to install a Growatt for it. I will be testing the furnace with my VE system in the meantime.
 
Hey All, brand new to the forum here. I was searching around but maybe you could point me in the right direction. I just bought the Growatt 24V SPF 3000TL LVM and (despite the red flags) a BigBattery.com 24V MULE – LiFePO4 – 120Ah – 3kWh battery. My questions are, do people wire in a breaker between the battery and the inverter with this setup? If so how big should it be? 200A?

Also, BigBattery.com ships with battery cables that are 6 gauge, but I thought they would be like 4 or even 2 gauge? Should I make new ones with bigger gauge wires or should ones that it comes with suffice?

Thanks for any help you can provide, and if you have any other tips I would love to hear them.
 
I believe that battery comes with a built-in fuse, and an Anderson connector (acceptable disconnecting means). Wire size would depend on length and amperage. Not sure what the output is of the mule.
 
According to the data sheet info from BigBattery.com's (partial data sheet below), 130 Amps under load? Max charge current is is 100 Amps? The length between the inverter and battery will be around 3 to 6 feet. There IS a built in 300A fuse built in. I THOUGHT I would need 1 or 2 gauge wire and a 175 amp breaker between them, but as a total newb I was hoping for a little direction. Thinking about it more now, it seems like that breaker would be too small with a built in 300A fuse IN the battery though. My understanding was that the 300 fuse was to protect the battery, but that wouldn't protect the wires from overheating or catching fire.

The response I got from BigBattery wasn't very helpful. The response was "we have never had problem with our battery cables". No matter the question, about breakers, gauge, spark prevention... I got the same canned response. Hence, I am here...

Again, Thank you so much for any help you can provide!

24V MULE – LiFePO4 – 120Ah – 3kWh
kWh Capacity:3kWh
Ah Capacity:120Ah
Cell Configuration:8S
Max Continuous Discharge Current Amps:130
Max Continuous Power Watts:3328
Max Discharge Peak Current Amps:350 (6 Seconds)
Max Charge Current Amps:100
 
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Personally, I would use 2 gauge and a 125a breaker.
But, someone else will probably be along soon, to crunch the numbers.
 
I use a fuse and a disconnect - no breaker. When I was building my system finding a rated breaker was a challange. however since then there are some inexpensive alternatives that would work.
 
I use a fuse and a disconnect - no breaker. When I was building my system finding a rated breaker was a challange. however since then there are some inexpensive alternatives that would work.

What size fuse did you use? The only size breaker close to 125A is 120A that I can find that is a surface mount style.
 
Well.... RTFM I guess, I DO really appreciate all the input and it aligns nicely with what I finally got to reading in the manual. Just putting all that I found out here incase anyone else is looking for it. Obviously, this is for one unit and people should follow this instructions for multiple units in parallel.

Wiring Specification
SPF 3000TL LVM-24P​
  • 1*2AWG
  • 2*6AWG
Recommended AC input and output cable size for each inverter:
SPF 3000TL LVM​
  • 8 AWG
Install the breaker at the battery and AC input side. This will ensure the inverter can be securely disconnected during maintenance and fully protected from over current of battery or AC input.

Recommended breaker specification of battery for each inverter:
SPF 3000TL LVM-24P - 1 unit
  • 150A/32VDC
  • I choose 125A per the recommendations from this groups and Ian from Watts 24/7 based on MY battery's Max Continuous Discharge Current
Recommended breaker specification of AC input with single phase:
  • 50A breaker for only 1 unit, each inverter should have a breaker at its AC input.
Thanks again for all the help!
 
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OK OK OK

So I have everything setup but for SOME reason and maybe somebody can help me here I have a constant 15A load on the battery even though it's not connected to anything other than the inverter itself. When it is charging it shows no load but otherwise it is there. So the battery just keeps draining and recharging (from grid, there are no panels yet), see graph below. Can anyone explain this?

Even when i turn the inverter off the 15A load on the battery exists. BUT WHEN I unplug the Growatt SPF 3000TL LVM-24P the draw drops to 0 Amps on the battery's display and it no longer drains. I called bigbattery.com and they walked me through some diagnostics and the battery is just fine...

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the long stable line is when the inverter was unplugged from the battery so i could test to see if the voltage would drop.
PXL_20220415_183839264.jpgPXL_20220415_183622620.jpg
 
That's too high, to be inverter idle draw alone.
I would check with a clamp meter. Maybe, the reading is wrong.
 
Yeah, I agree... but i can see it discharging in front of my eyes so i don't think the reading is wrong I mean look at this graph from solar assistant too... (the raspberry pi is connected to grid power not the inverter)

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I can also see these Green and Red LEDs blinking constantly on the circut boards, not sure what those are doing but you'd think they wouldn't constantly blink. To be clear... they are not the charge and fault LEDs above the screen.
 
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