The solar chargers are small, how does everyone deal with this?

[drps10]

I am in the beginning stages and building on paper my setup. I will be going with Victron 48v. I am designing about a 4-5kw solar array and I want to do series as much as possible. My run will be around 250' from my setup thus me keeping it in series as much as possible for smaller wire (accommodating for voltage drop). Victron has their 250/100 and their big guy smartsolar 450/100. If I were to keep it all in series, Neither one of those will be large enough for my array. Do I just have to big the expensive bullet and buy multiple controllers? Then I have to have multiple runs of wire (or going high amps would be the same price) . Do I do a combinations of series and parallel and try to stay under the requirements? At one point in my math, I would have 3S4P and need 3awg wire for the 250' run or maybe Aluminum wire. Just to stay under the 250/100. Or I could spend $1300 and get the SmartSolar and play around with the configuration.

Seems there has to be a better way! I've seen some large system arrays and I can't imagine everyone having to buy a new charge controller when they want to add more panels.

 

[timselectric]

For clarification a Victron 250/100 means 250v max input with a charging output of 100a to the battery.

 

[sunshine_eggo]

I am in the beginning stages and building on paper my setup. I will be going with Victron 48v. I am designing about a 4-5kw solar array and I want to do series as much as possible. My run will be around 250' from my setup thus me keeping it in series as much as possible for smaller wire (accommodating for voltage drop). Victron has their 250/100 and their big guy smartsolar 450/100. If I were to keep it all in series, Neither one of those will be large enough for my array. Do I just have to big the expensive bullet and buy multiple controllers? Then I have to have multiple runs of wire (or going high amps would be the same price) . Do I do a combinations of series and parallel and try to stay under the requirements? At one point in my math, I would have 3S4P and need 3awg wire for the 250' run or maybe Aluminum wire. Just to stay under the 250/100. Or I could spend $1300 and get the SmartSolar and play around with the configuration.

Seems there has to be a better way! I've seen some large system arrays and I can't imagine everyone having to buy a new charge controller when they want to add more panels.

250' run is special case. Most don't need this, and most equipment does not support it.

There are some 600v MPPT. IIRC Schneider has one.

Maintaining a 3% voltage drop isn't mandatory. Knowing that the voltage drop corresponds directly to power loss.

Since each of the 100A controllers have a ~6kW peak output, I used that for this exercise. 180Vmp (6S3P 37Voc panels - about 330w) and 33A of current on the 250/100:

Voltage Drop Calculator

This free voltage drop calculator estimates the voltage drop of an electrical circuit based on the wire size, distance, and anticipated load current.

www.calculator.net

Single pair of 8awg yields 5.76% voltage drop.

10S2P on the 450/100:

Voltage Drop Calculator

This free voltage drop calculator estimates the voltage drop of an electrical circuit based on the wire size, distance, and anticipated load current.

www.calculator.net

Single pair of 8awg yields 2.30% voltage drop.

The question becomes, how much do you want to spend on the cable run, and is it worth the benefit?

 

[SamDeleted]

100amps @ 48v = 4,800w (4.8kw)


I think the victron 450v/100amp should be suitable for your needs ,




For instance, if you had 12x425w panels (5.1kw array) you could split them in half and two strings, run them in 6s2p

Even if they were on the higher end voltage wise eg 50voc , 6 panels in series=300voc , well below the 450v max



The only thing you need to watch out for is the max PV input amps of your chosen MPPT, these 425w panels are 10.25amps each , so 2 parallel the whole array would output 20.5amps


That 20.5amps could be over the rating of the mppt . I don't know others might be able to help

 

[SamDeleted]

There are some 600v MPPT. IIRC Schneider has one

Morningstar TS-MPPT-60-600V Charge Controller - SunWize | Power Independence

the TriStar TS-MPPT-60-600V-48 controller does much more than efficiently charge batteries; it provides remote communications, data logging, adjustability and metering. The TriStar MPPT 600V controller is the only 600-volt PV controller to offer open communication protocols and true...

www.sunwize.com

They don't come cheap !

 

[drps10]

You guys are awesome and fast!! I did see the Morningstar but I didn't look up the price yet.

I didn't really think of the voltage drop like that! I am use to dealing with maintaining the voltage on long runs to an A/C or Heat Pump or something. If I'm willing to sacrifice price for voltage drop then that is on me!

250' run is special case. Most don't need this, and most equipment does not support it.

How does some equipment not support this? What do i need to look out for?

 

[sunshine_eggo]

Morningstar TS-MPPT-60-600V Charge Controller - SunWize | Power Independence

the TriStar TS-MPPT-60-600V-48 controller does much more than efficiently charge batteries; it provides remote communications, data logging, adjustability and metering. The TriStar MPPT 600V controller is the only 600-volt PV controller to offer open communication protocols and true...

www.sunwize.com

They don't come cheap !

I knew there was another, but I couldn't think of that one...

 

[sunshine_eggo]

How does some equipment not support this? What do i need to look out for?

I just meant that since most runs aren't that long, most MPPT aren't capable of very high operating voltage.

While I computed it with a single input, it's also worth noting that the 450/100 is two separate 50A MPPT, so you'd need to run two separate pairs of conductors.

 

[drps10]

I just meant that since most runs aren't that long, most MPPT aren't capable of very high operating voltage.

While I computed it with a single input, it's also worth noting that the 450/100 is two separate 50A MPPT, so you'd need to run two separate pairs of conductors.

Thank you. this would also help in future proof of another array vs another controller

 

[Supervstech]

Most DIY stuff stays 500V and below for ease of handling.
450V gives you a lot of options.
The EG4 6548 has a 500V pv input if that helps.
Several other problems with that unit though.

 

[drps10]

Most DIY stuff stays 500V and below for ease of handling.
450V gives you a lot of options.
The EG4 6548 has a 500V pv input if that helps.
Several other problems with that unit though.

i have considered that unit along with MPP too, but I like the options to build it how I need, the low inverter usage, and the built proof the Victron System is!

 

[Supervstech]

i have considered that unit along with MPP too, but I like the options to build it how I need, the low inverter usage, and the built proof the Victron System is!

Yeah...
When I outgrow my outback and Magnum stuff I will get victron I think...
Unless some amazing low loss super tech comes out by then.

 

[drps10]

Without creating a new thread, maybe there is a fast and easy answer to this question. I am still looking at Solar Panels and have not decided on anything yet (companies, Watt size, etc..)

Do higher Voc numbers mean better or worse panel? Does it just correlate with the Watt it will produce and the overall size will dictate the Voc? I've seen some with higher numbers than others and I just don't know what to look at just yet with panels.

 

[timselectric]

You really need to pick your SCC first. And match your panels to it.

 

[sunshine_eggo]

Without creating a new thread, maybe there is a fast and easy answer to this question. I am still looking at Solar Panels and have not decided on anything yet (companies, Watt size, etc..)

Do higher Voc numbers mean better or worse panel? Does it just correlate with the Watt it will produce and the overall size will dictate the Voc? I've seen some with higher numbers than others and I just don't know what to look at just yet with panels.

Vmp * Imp = rated Watts

Cell count affects Vmp/Voc.

Vmp is about 0.5V per cell.

Vmp is about 80-83% of Voc

36 (12V), 60 and 72 (24V) cell panels are the most common. You might see 120 and 144 cell panels, those are usually half cell panels were you get 2X 60 or 72 panels in parallel in the same panel.

Manufacturing methods and such can influence all of the above.

Selecting the proper panel typically entails considering size, weight, Voc/Vmp and Isc/Imp for a given application.

I used a 37Voc/30Vmp, 11A Imp (330W) 60 cell panel for my calculations.

 

[Shimmy]

You really need to pick your SCC first. And match your panels to it.

You think so? I'd say it is best to work in both directions at once: 1) look at panel options and note Voc, kW, dimensions and cost; and 2) look at SCCs and see what the operating MPPT voltage range (and overload) is. See what combinations of panels and SCCs meet your needs. When you just look in one direction then you blind yourself to better options.

IMO, anything over 200' run really should have a higher string Vmp than 200V, which is going to end up with a Voc with temperature adjustments safely over 250V. The 60-cell panels are better suited for a 250V MPPT, as you can put 5 in series.

 

[drps10]

I just meant that since most runs aren't that long, most MPPT aren't capable of very high operating voltage.

While I computed it with a single input, it's also worth noting that the 450/100 is two separate 50A MPPT, so you'd need to run two separate pairs of conductors.

I'm still new and learning! Where did you find that each tracker is 50a? The data sheet shows the Short Circuit of the 450/100 is 20a per tracker. What happens if I go over that? Can the amps go over like over-panelling?

The system that I just quickly put together is:
10x 425w Solar Panels wired in a 5s2p configuration will result in those 4250 Watts being delivered to the charge controller at 314V when the temperature drops to the low temperature as previously defined.


Important Numbers:

• Solar Array Wattage: 4250W
• Temperature Compensated Array Voltage: 314V
• Controller Output Amperage: 74A
• Array Short Circuit Amperage: 21.48A

 

[timselectric]

You think so?

Actually, nope. I take that back. lol
You need to work out different combinations of all components. Until you have what would work best for you.

 

[sunshine_eggo]

I'm still new and learning! Where did you find that each tracker is 50a? The data sheet shows the Short Circuit of the 450/100 is 20a per tracker. What happens if I go over that? Can the amps go over like over-panelling?

The system that I just quickly put together is:
10x 425w Solar Panels wired in a 5s2p configuration will result in those 4250 Watts being delivered to the charge controller at 314V when the temperature drops to the low temperature as previously defined.


Important Numbers:

• Solar Array Wattage: 4250W
• Temperature Compensated Array Voltage: 314V
• Controller Output Amperage: 74A
• Array Short Circuit Amperage: 21.48A

100A is total OUTPUT on two trackers, 50A each. The 4000W/tracker implies they can each output more than 50A, but the total must be limited to 100A. In this case, 4000W/57.6V = 69A max on one tracker with the second limited to 31A. Easier to just say 50A EA

18A is the max Imp INPUT from the panels.
20A is the max Isc INPUT from the panels.

Thus, my theoretical 11A panels in 2P would not be usable as they would bust the 20A input limit.

These kinds of limits are more typical on high voltage MPPT. This means it's even more restrictive on panel configuration and selection. By comparison, the 250/100 can handle 70A on the input allowing for more parallel strings with more over-paneling options.

 

[G00SE]

Midnite has the Barcelona which is 600v and 200a so it supports close to 11000w of panels
They also have the hawks bay in both 120a as well as 80a (both 600v)
Schneider has the 600/100 units (would need two to equal the Barcelona)
Seems the Victron has some quirks in threads I’ve read but also seems like a pretty healthy charge controller as well