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davy

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hi solar fans first i have a 12V system with a 2000W renogy inverter and 3x 50A power queen batteries connected in parallel.
i have a victron mppt controller 150/35. here i use a 40 AGU fuse.
for my system i use a 150A mega fuse ( the black box on the photo )
what do u think about this system?I learned a lot from Brad Cagle on youtube,maybe he is here also on this forum.
 

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Yes @BradCagle is on this site as a forum member.

Since you have three batteries wired in parallel, you might want to review the thread in the link below.

 
hi solar fans first i have a 12V system with a 2000W renogy inverter and 3x 50A power queen batteries connected in parallel.
i have a victron mppt controller 150/35. here i use a 40 AGU fuse.
for my system i use a 150A mega fuse ( the black box on the photo )
what do u think about this system?I learned a lot from Brad Cagle on youtube,maybe he is here also on this forum.

Cool little system!

Only thing I would say is your 2000w inverter will be a little more power hungry (when loaded heavy) than your system will be able to provide.
 
Cool little system!

Only thing I would say is your 2000w inverter will be a little more power hungry (when loaded heavy) than your system will be able to provide.
Nice to see u here on this forum brad.Thx for the video's on youtube!The max load that i use on this small system is around 130A so that's why I use 150A fuses.the main mega fuse is 150A.should i put a 150A fuse on the wire to the inverter to?or is this one main fuse enough?thx
 
Nice to see u here on this forum brad.Thx for the video's on youtube!The max load that i use on this small system is around 130A so that's why I use 150A fuses.the main mega fuse is 150A.should i put a 150A fuse on the wire to the inverter to?or is this one main fuse enough?thx

Over-current protection is there for the wire, not the device. I have a Class T fuse between my LiFePO4 battery bank and the main bus bar. Then a MEGA fuse between the main bus bar and the inverter.
 
Nice to see u here on this forum brad.Thx for the video's on youtube!The max load that i use on this small system is around 130A so that's why I use 150A fuses.the main mega fuse is 150A.should i put a 150A fuse on the wire to the inverter to?or is this one main fuse enough?thx

You're welcome, glad you like them :)

On the max load, if you know to keep it under 130A you're fine. You might want to consider as your battery bank drains, and you get close to your low voltage cutoff on your inverter, usually around 10.5v you'll be pulling more current to keep up with the power demand. So basically that 130A could rise quickly at the low end of the battery state of charge. You might drain the system to see what the current looks like when the bank is about to be depleted.

As for the fuse question, just as @HRTKD mention the fuse is to protect the wire from bursting into flames if it's overloaded. The way you have it there is a potential problem. Your MPPT could be providing 35A to that bus bar, and then the battery could be providing 150A
You now potentially have 185A going over the wire that is not fused to your inverter.

So yes, you absolutely should put a 150A fuse on the wire going to the inverter.

Also a note about your wire, are you sure it can handle 150A? Looks like 2awg, but the reality is not all wire is created equal. Some 2awg cant handle 150A, while other 2awg can handle more than 150A per the manufacture. So please make sure you know what the manufacture specs for the wire, if you don't know, then you might want to buy some wire that provides these specs (and you trust the company :) ).

TEMCo welding cable is good stuff, and they give you an amp chart

I've also used the windy nation welding cable
 
Very cool system. What and how many solar panels do you have for the system?
I have 4 solar panels of 110W each connected in series.
Over-current protection is there for the wire, not the device. I have a Class T fuse between my LiFePO4 battery bank and the main bus bar. Then a MEGA fuse between the main bus bar and the inverter.
Do u have a photo of youre system?yes i have read that class T fuse are the best protection.but i have a small 150A system so a mega fuse is fine.they say that on a dutch forum ( im from belguim )
 
You're welcome, glad you like them :)

On the max load, if you know to keep it under 130A you're fine. You might want to consider as your battery bank drains, and you get close to your low voltage cutoff on your inverter, usually around 10.5v you'll be pulling more current to keep up with the power demand. So basically that 130A could rise quickly at the low end of the battery state of charge. You might drain the system to see what the current looks like when the bank is about to be depleted.

As for the fuse question, just as @HRTKD mention the fuse is to protect the wire from bursting into flames if it's overloaded. The way you have it there is a potential problem. Your MPPT could be providing 35A to that bus bar, and then the battery could be providing 150A
You now potentially have 185A going over the wire that is not fused to your inverter.

So yes, you absolutely should put a 150A fuse on the wire going to the inverter.

Also a note about your wire, are you sure it can handle 150A? Looks like 2awg, but the reality is not all wire is created equal. Some 2awg cant handle 150A, while other 2awg can handle more than 150A per the manufacture. So please make sure you know what the manufacture specs for the wire, if you don't know, then you might want to buy some wire that provides these specs (and you trust the company :) ).

TEMCo welding cable is good stuff, and they give you an amp chart

I've also used the windy nation welding cable
honestly, I don't know ahaha...I paid a lot for this 35mm2 cable.the only problem I've encountered was with a cheap ANL fuse,the fuse and holder and the end of the cable that connected to the fuse getting very hot.i have replace it with a mega fuse and no issue no more.thx for the tip i have to buy another fuse and holder so i can instal it on the inverter wire.
 
Do u have a photo of youre system?yes i have read that class T fuse are the best protection.but i have a small 150A system so a mega fuse is fine.they say that on a dutch forum ( im from belguim )

The Class T fuse is at the top right. I kind of fudge it by using a single Class T fuse for both batteries. If I make changes, each battery will get its own fuse.
1700245425713.png
 
The Class T fuse is at the top right. I kind of fudge it by using a single Class T fuse for both batteries. If I make changes, each battery will get its own fuse.
View attachment 178357
That's a nice setup. Still too complicated for me. I'm happy that I could put together a small system like i have.thx for sharing.
 
So I placed a 150A mega fuse on the cable to the inverter and a 40A mega fuse on the cable of the MPPT controller. Thanks everyone for the great help!and brad I'll see you again on youtube;)
 
The Class T fuse is at the top right. I kind of fudge it by using a single Class T fuse for both batteries. If I make changes, each battery will get its own fuse.
About your image, are those copper bars? Did you cut those yourself and buy stock somewhere? What thickness and width did you use?
 
About your image, are those copper bars? Did you cut those yourself and buy stock somewhere? What thickness and width did you use?

Yes, they're copper bars that I made myself from stock. 3/8" thick by 1" wide. I was using a thinner bar that was only 3/4" wide, but it didn't make use of the entire contact surface on a couple of the devices. I bought the bars online from midweststeelsupply.com. I think they were 72" long.
 
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