(6) 100 watt panels with 40a MPPT charge controller in 3S2P?

[H31ST]

Hey everybody, I'm new to this forum and hoping I can find the help I need. I have (6) 100 watt Renogy panels with Voc 21.6v, Isc 6.24a that I am hooking up to a Renogy 40a MPPT charge controller, (2) 200ah 12v Renogy deep cycle AGM batteries, and a Kinverch 5000 watt inverter. From what I have researched I think the best option is a 3S2P configuration, however I want to ensure that I am doing it the 'best' and safest way before I begin, as this is my first 'major' solar project. Is 3S2P the best configuration or would a 2S3P or 6S be better? also if I am correct with the 3S2P configuration, would I need fuses? and where would they be placed?

I am confident that the installation wont be an issue, however I do not have all that much experience with electrical so I want to ensure that my plan is solid before I proceed further.

Any guidance or advice is appreciated. Thanks for any replies in advance.

 

[Bud Martin]

Do the real world experiment with them to see which one gives you the best result as long as the Total Voc does not exceed the max PV input Voltage spec of the solar charge controller, the Voc will rise when it gets cold so you have to factor that in also.
If you parallel more than two strings of panel together then you will need to have fuse for each string, it is a good idea to have din mount PV fuse holder for each string since it will make it easier to troubleshoot the problem.

 

[mikefitz]

6s will exceed the controller maximum input voltage, (100 volts). Typical OC volts of a 100 watt panel is 22 volts. 3s2p will be OK.
You only need panel fuses for 3 strings or more .
A fuse / breaker ar the battery end of controller feed cable.
You will need substantial cables for a 5000 watt inverter.
Hope its a 24 volt system . 400 Ah of AGM battery is a bit light for a 5000 watt inverter at full power.

Mike

 

[wmgeorge]

I also have the same panels.... 3S2P works fine on the 40 amp MPPT controller. I have 3 100 aH batteries on a low freq 2000 watt Invertor.

 

[H31ST]

6s will exceed the controller maximum input voltage, (100 volts). Typical OC volts of a 100 watt panel is 22 volts. 3s2p will be OK.
You only need panel fuses for 3 strings or more .
A fuse / breaker ar the battery end of controller feed cable.
You will need substantial cables for a 5000 watt inverter.
Hope its a 24 volt system . 400 Ah of AGM battery is a bit light for a 5000 watt inverter at full power.

Mike

would you recommend wiring my two 12v 200ah batteries in series than using a 24v to 12v converter? The only reason I got the 5000 watt inverter is so I can expand the system a decent amount, whether that be on my current RV, or if I decided to take it off and install it on a house. I realize I would then need a new charge controller but I was told before I bought the 5000 watt inverter that it would be fine with a 12v system. What would happen if I were to use my current inverter on a 3S2P configuration with my 400ah of batteries? or should I just get one more battery for now and a 12v system would be fine?

Thanks for the response

 

[H31ST]

I also have the same panels.... 3S2P works fine on the 40 amp MPPT controller. I have 3 100 aH batteries on a low freq 2000 watt Invertor.

Awesome!!! thanks for the reply. Do you think a 5000 watt inverter is too much? will it take away from how long I will be able to use power before the batteries are drained? I am very new to solar but hope to learn as much as I can and ultimately have a very efficient clean energy supply. I bought the 5000 watt inverter so I could expand the system in the future? If I need to get a new one I will, however I would rather get an additional 200ah or 100ah battery and be able to store more power, than to spend money on a new inverter and have less charge,

 

[wmgeorge]

Awesome!!! thanks for the reply. Do you think a 5000 watt inverter is too much? will it take away from how long I will be able to use power before the batteries are drained? I am very new to solar but hope to learn as much as I can and ultimately have a very efficient clean energy supply. I bought the 5000 watt inverter so I could expand the system in the future? If I need to get a new one I will, however I would rather get an additional 200ah or 100ah battery and be able to store more power, than to spend money on a new inverter and have less charge,

On 12 volts is way over kill, I only have a low freq 2000 watt on mine and going to a 3000 watt would really be pushing the limits on ampere draw from the batteries. I only have 3 100 aH LFP batteries and perhaps adding a 4th but not now. If you never plan on using more than 2000-3000 watts your ok with the 5.

 

[H31ST]

On 12 volts is way over kill, I only have a low freq 2000 watt on mine and going to a 3000 watt would really be pushing the limits on ampere draw from the batteries. I only have 3 100 aH LFP batteries and perhaps adding a 4 but not now. If you never plan on using more than 2000-3000 watts your ok with the 5.

I listed my 5000 watt inverter for sale so I can hopefully buy a 3000 Watt pure sine to maximize my runtime. what is the max amount of ah for batteries can I have on a 3000 watt?

 

[mikefitz]

Your 5000 watt inverter will be OK at lower power outputs but will be less efficient by a few % and have a higher standby power than a lower power unit.

Rough rule of thumb is the battery and cables should be able to provide a current 1/10 of inverter watts at 12 volt and 1/20 at 24 volts.

Thus a 12v 5000 watt inverter at full power is 500 amps that all connections and cables should be designed for.

The inverter will need to be selected for the expected load, don't just pluck values out of the air. A quality inverter will be more reliable than an Amazon special.

Do consider appropate protective circuits on the inverter AC output if it's a permanent install with multiple appliances. AC 120/230 volts can kill,
.

Mike

 

[wmgeorge]

Expect to pay $600 - $1500 plus for a good low freq 3000 watt inverter. The 12 volt supply voltage is a draw back on larger inverters 3000 watts would be about 250 amps not including all the losses.

 

[H31ST]

Okay, then what watt inverter do you personally think would be the most efficient and to maximize my runtime if I were to have 400ah of battery, or if I upgraded to 600ah. I know it goes based off usage and a lot of other variables, but from your experience what would be the 'best' to use if I were to keep 2 batteries, or upgrade to 3.

Again thank you for all the advice, and sorry for the many questions. I just want to ensure I am getting the most out of my system.