Panel configuration recommendations for 6.5kw LV6548 and CanadianSolar (320w)

[jeffreyhuffman]

Hi,
I've purchasing a solar inverter reviewed on this site. I've also acquired 30 CS panels. Specs for both below are documented in the images below. Current storage consideration is four to eight 200ah, 12v Renogy batteries, but I have not purchased those yet. I don't have enough experience to configure the panels optimally. I would appreciate any expert insight or recommendations.




The system will support a completely off-grid, vacation-property deployment. Location is rural northern California, in Calaveras County, on a mountain side ascending moderately westward, but open and clear to the east and south.

Follow-up question is, what is the furthest distance I can reasonably plant the PV array from the solar inverter with this system. I'm more than willing to spend a few hundreds of dollars to upgrade wire, but obviously prefer not to spend thousands of dollars. The contextual variable is geography: Further distance equals higher on the hill equals increased access to late day sun. (A couple of hundred feet would be a big win, especially in the winter months.)

Thanks in advance for any help.
Cheers.

 

[markansas]

Hi,
I've purchasing a solar inverter reviewed on this site. I've also acquired 30 CS panels. Specs for both below are documented in the images below. Current storage consideration is four to eight 200ah, 12v Renogy batteries, but I have not purchased those yet. I don't have enough experience to configure the panels optimally. I would appreciate any expert insight or recommendations.


View attachment 73399View attachment 73400

The system will support a completely off-grid, vacation-property deployment. Location is rural northern California, in Calaveras County, on a mountain side ascending moderately westward, but open and clear to the east and south.

Follow-up question is, what is the furthest distance I can reasonably plant the PV array from the solar inverter with this system. I'm more than willing to spend a few hundreds of dollars to upgrade wire, but obviously prefer not to spend thousands of dollars. The contextual variable is geography: Further distance equals higher on the hill equals increased access to late day sun. (A couple of hundred feet would be a big win, especially in the winter months.)

Thanks in advance for any help.
Cheers.

if i could change things the battery is one of them i would go with and will later do so..

48V 100AH LiFePower4 Battery by EG4​

it is 1499 plus shipping and the reason why is the life cycle is great.. 10 15 years if ya dont treat it hard and its and this i really like its all in one package.. battery mang. the hook up to the inverter .. its almost plug and play just add more as you can.. mark

 

[Lt.Dan]

Optimally would be 2x seperate 6s2p arrays with those panels, but thats only 24 panels. You will have 6 left over that you can't use. I have a very similar setup that has just over 200ft run of 10ga PV wire with no problems. Idk how much farther I would want to go than that though.

 

[sunshine_eggo]

Optimally would be 2x seperate 6s2p arrays with those panels, but thats only 24 panels. You will have 6 left over that you can't use. I have a very similar setup that has just over 200ft run of 10ga PV wire with no problems. Idk how much farther I would want to go than that though.

The only concern I have about 2P on this unit is you may be over the 18A limit from time to time. I've always held the belief a little won't hurt, but several on the forum indicate this is a hard limit.

IMHO, these charge controllers are not well designed. 4000W claimed on a 250Voc/18A limit? That only allows for 250 * 18 = 4500W, and that doesn't allow for Vmp or cold temp voltage effects.

 

[Lt.Dan]

The only concern I have about 2P on this unit is you may be over the 18A limit from time to time. I've always held the belief a little won't hurt, but several on the forum indicate this is a hard limit.

IMHO, these charge controllers are not well designed. 4000W claimed on a 250Voc/18A limit? That only allows for 250 * 18 = 4500W, and that doesn't allow for Vmp or cold temp voltage effects.

These have been confirmed to be able to be overpanneled up to 24a without damage. They will clip at 18a though. No worries of that. I do it everyday.

The LV6548 has 2x inputs, with a 250VOC and 18a ISC, with a max of 4000w each.

A 6s of his panels will make 240v, leaving 10v for colt temp fluctuations. 6s2p making 3840w. Perfectly beneath the limits of this inverter

 

[jeffreyhuffman]

if i could change things the battery is one of them i would go with and will later do so..

48V 100AH LiFePower4 Battery by EG4​

it is 1499 plus shipping and the reason why is the life cycle is great.. 10 15 years if ya dont treat it hard and its and this i really like its all in one package.. battery mang. the hook up to the inverter .. its almost plug and play just add more as you can.. mark

Thanks Mark.

How do I compare the utility of a single 48v/100AH battery with four 12V/200AH batteries in series?

 

[jeffreyhuffman]

These have been confirmed to be able to be overpanneled up to 24a without damage. They will clip at 18a though. No worries of that. I do it everyday.

The LV6548 has 2x inputs, with a 250VOC and 18a ISC, with a max of 4000w each.

A 6s of his panels will make 240v, leaving 10v for colt temp fluctuations. 6s2p making 3840w. Perfectly beneath the limits of this inverter

Thanks very much Lt. Dan and Sunshine_eggo. Great information and very insightful.

 

[sunshine_eggo]

These have been confirmed to be able to be overpanneled up to 24a without damage. They will clip at 18a though. No worries of that. I do it everyday.

The LV6548 has 2x inputs, with a 250VOC and 18a ISC, with a max of 4000w each.

A 6s of his panels will make 240v, leaving 10v for colt temp fluctuations. 6s2p making 3840w. Perfectly beneath the limits of this inverter

Glad to hear that 18A isn't a hard limit; however, only 10V margin at the top means it can never get colder than about 50°F for his panel's temp coeff, -0.29%.

 

[markansas]

Thanks Mark.

How do I compare the utility of a single 48v/100AH battery with four 12V/200AH batteries in series?

if i am right if you used 4 12v 200ah it would be 48v at 200ah.. so that is bigger .. me just thinking all in one for those 4 batterys to work you need to tie the pos to pos and let them sit awhile to balance out then string them into a 48 volt string might need battery man. system also. me i am just lazy i guess and do understand i might miss something like use a resistor to pre charge the cap in the inverter and the all in one has that pre charger built in. its those little things that can cost more in the long run. bigger better tho

 

[jeffreyhuffman]

Glad to hear that 18A isn't a hard limit; however, only 10V margin at the top means it can never get colder than about 50°F for his panel's temp coeff, -0.29%.

Thanks again!

Confirming in a diagram....


The property is in the Sierra foothills but it's high desert, and winters are very mild. The sun can be brutal, even on "cold" days. The temperature probably drops below freezing over night a couple of times a year, but I haven't ever seen snow (in over 10 years). It's below 50, though, when the sun isn't shining.

 

[jeffreyhuffman]

if i am right if you used 4 12v 200ah it would be 48v at 200ah.. so that is bigger .. me just thinking all in one for those 4 batterys to work you need to tie the pos to pos and let them sit awhile to balance out then string them into a 48 volt string might need battery man. system also. me i am just lazy i guess and do understand i might miss something like use a resistor to pre charge the cap in the inverter and the all in one has that pre charger built in. its those little things that can cost more in the long run. bigger better tho

Yes, got it. Very helpful. Thanks, Man!

 

[sunshine_eggo]

Thanks again!

Confirming in a diagram....
View attachment 73406

The property is in the Sierra foothills but it's high desert, and winters are very mild. The sun can be brutal, even on "cold" days. The temperature probably drops below freezing over night a couple of times a year, but I haven't ever seen snow (in over 10 years). It's below 50, though, when the sun isn't shining.

Then you need to go 5S2P. In a normal temperature cycle, the coldest time in any 24 hour period is right before dawn. Whether the sun is shining or not doesn't matter. At sunrise, there's not enough energy to heat the air significantly, but there's enough light to get full panel voltage well before the panels heat up.

This isn't an intellectual discussion. If you get that cold, you will violate the 250Voc limit, and you may damage the MPPT. You need to stick with 5S.

if i am right if you used 4 12v 200ah it would be 48v at 200ah.. so that is bigger .. me just thinking all in one for those 4 batterys to work you need to tie the pos to pos and let them sit awhile to balance out then string them into a 48 volt string might need battery man. system also. me i am just lazy i guess and do understand i might miss something like use a resistor to pre charge the cap in the inverter and the all in one has that pre charger built in. its those little things that can cost more in the long run. bigger better tho

No. You need to charge them to full individually, or as a single parallel 12V battery. Preferably, both, in that order.

Sitting in parallel only equalizes voltage. It does very little to equalize the actual state of charge, which is what really matters.

 

[markansas]

Thanks again!

Confirming in a diagram....
View attachment 73406

The property is in the Sierra foothills but it's high desert, and winters are very mild. The sun can be brutal, even on "cold" days. The temperature probably drops below freezing over night a couple of times a year, but I haven't ever seen snow (in over 10 years). It's below 50, though, when the sun isn't shining.

sorry i think this is one of those little things i worry about it looks right dont worry about the current as much just dont over voltage the input of the inverter. sure someone will remind me if i am wrong
and if i remember right one set of panels can face morning sun to get you started and the other face the afternoon sun to end your day..
unless ya have tracking..

 

[markansas]

Then you need to go 5S2P. In a normal temperature cycle, the coldest time in any 24 hour period is right before dawn. Whether the sun is shining or not doesn't matter. At sunrise, there's not enough energy to heat the air significantly, but there's enough light to get full panel voltage well before the panels heat up.

This isn't an intellectual discussion. If you get that cold, you will violate the 250Voc limit, and you may damage the MPPT. You need to stick with 5S.



No. You need to charge them to full individually, or as a single parallel 12V battery. Preferably, both, in that order.

Sitting in parallel only equalizes voltage. It does very little to equalize the actual state of charge, which is what really matters.

thanks see all in one for me.. grin its those little things

 

[sunshine_eggo]

Thanks Mark.

How do I compare the utility of a single 48v/100AH battery with four 12V/200AH batteries in series?

A single 48V is also balanced at the cell level. 4X 12V means the cells are only balanced within each 12V unit.

But as was pointed out, the 4X 12V scenario has 4X the capacity.

Also, worth noting that BATTLEBORN recommends that you break down series batteries made from 12V and charge them individually once a MONTH.

That's a down side.

Another option to address that is 12V "balancers" that monitor the voltage of each 12V and actively pass current from high to low. IMHO, the presence of an active balancer removes all downsides associated with 12V in series.

 

[markansas]

and that is my point all the little things i might forget to do .. i am 65 in 10 years i will not want to do much more than use it not repair it. so many things to think on.. however i am not the op here and being old and bored glad to bounce ideas off others.. mark

 

[sunshine_eggo]

and that is my point all the little things i might forget to do .. i am 65 in 10 years i will not want to do much more than use it not repair it. so many things to think on.. however i am not the op here and being old and bored glad to bounce ideas off others.. mark

My dad just retired at 75. Now that he's retired, he has more time to spend working on classic Triumphs for side money. Don't sell yourself short.

No harm in engaging in a discussion for your own benefit.

Just don't take over the thread... start your own at that point.

 

[Lt.Dan]

Yes, I hadn't put into account for the temperature coefficient because we rarely see even remotely cold temps where im at.

 

[jeffreyhuffman]

Yes, I hadn't put into account for the temperature coefficient because we rarely see even remotely cold temps where im at.

Digging a bit more, I found that the manual recommends a configuration based on Vmp rather than Voc. (I saw that this topic was also discussed a bit in another thread.) This clip from the manual recommends 6s2p configuration for a slightly more powerful panal than mine. (See second and third rows from the bottom.)

 

[jeffreyhuffman]

A bit of an eye chart covered in Ragu, but I would definitely welcome any feedback.