Will this non match array work?

[solarvic]

Distance, 250 ft. from solar to solar charger. I don,t have enough of any 1 panel to achieve the voltage I need. What I have= 8 Shuco model S 180 SPU-4, 2 mitsubishi  PV-UD175mf5. Can,t find any more of them. I was told Mitsubishi made those shuco panels and they look identical to each oither and the specs or real close.I can get 4 of the kyocera KD185GX-LPU  panels if I don,t procrastinate too long as I heard they are bieing discontinued also. They are the closest I can find . I want to use 4 schuco 180, 1 mitsubishi 175 and 2 of the kyocera 185 in 2 separate strings for a Classic 300.
specs.
schuco  stc180w voc 30.4v vmp 24.2v  imp 7.45A  coldest day voc 36v warm 20.7   
mitsubi stc175w voc 30.2v vmp 23.9v  imp 7.32A  coldest day voc 35.8 v warm 20.4
kyocera stc185w voc 29.5v vmp 23.6v  imp 7.84A  coldest day voc 35.2 v warm 20.1
These stats are from a reputable inverters string chart. I also will be using #2 al urd wire from solar arrays to controler or a buss next to controler.. Are the specs close enough that the classic controler will track this setup and does it have the capacity to charge a 24vdc battery setup? Crazy or Bob I hope you have the answer.        :)solarvic

[niel]

vic,
when dealing with series strings you want the current to be close. the voltage does not come into play for being the same until putting it in parallel with another string. (also assuming the strings stay within the controller specs) what kind of imp figures are you talking about with all of the pvs? is each string going to use its own set of #2 wires or do you intend both strings to be combined and then sent over a single pair of #2 wires for + and -? once more info is presented then it can be determined if the #2 wire will suffice for certain at that run distance or what may be better to use. i can say preliminarilly that it most likely will work well even for both strings into a single pair of #2 wires going by the 7.84imp amps of the kc185s as it should be under a 1% v drop.

[Halfcrazy]

Solarvic

The Voltage of that array will be right in the window according to your record cold VOC temps. The real Problem is that the Classic250 is good for around 1800 watts of pv into a 24 volt battery and you have around 2500 watts. A single Classic150 could handle that but would require you to reconfigure the array.

Tell us how long the wire run one way is from the panels to the Classic and we can make some suggestions.

Half

[solarvic]

Niel and Half Krazy  250 ft. is the total one way distance from the junction box at panels to where the charge controlers would be located. I have a 500 ft roll of URD #2 aluminum wire. I was planing on combining my strings at the panel location and running i set of the #2 aluminum urd  wires to the charge controlers. So far I only have the 8 skuko panels @ 180 w each and 2 of the mitsubisha 175 panels. That is total of 10 panels which would give me close to the 1800 watt the classic 250 could handle.  I figured if I used the original proposed 12 panels that my VMP would be close between high 15 to 16 amp VMP Also I do have 2 100 ft lengths of #2 thhn copper wire I could use. I bought all this wire and solar panels before I retired and need to make do with what I have. Another alternitive for wire is I have 2 reels of 500 ft each #8 copper thhn wire I could use with 2 runs of 250 ft to the charge controlers. I wanted to use the aluminum wire as I probably won,t have any other use for it. I kind of wanted to save my 100 ft  pcs of #2 copper for my dc generator. 

[niel]

vic,
i overlooked the al reference so be aware that i was basing my findings using copper wires as aluminum wires will have more resistance and a higher voltage drop. i did not design my calculator on the use of al wire as i'm not too fond of it, but there are other calculators out there too. i did figure it for a higher voltage on the vmp initially than it is, but it is still about 1% with a 500ft total length of #2 copper wire. aluminum wire will be worse, but it will still be less than 2%. vmp total should be 168.7v with voc over 210v. i figured this at 15.68a which is probably a tad higher than you will see and is the result of 2 strings. of course you don't want to exceed the controller's power handling limits so i would imagine you will reduce the voltage which will worsen the voltage drop some more. are you sure you can't do this for a 48v battery bank as then you could use all of the pvs?

[solarvic]

Niel, Arizona wind and solar has a real nice voltage drop calculator. It does al and copper.  I think The classic 150 would work on 3 strings of 4 panels, but the panels types are different in each string. At 95f the vmp is 82.2 Volt.  voltage drop3.85% =3.16vdc @ 245 ft. Which I can live with. We don,t see 95f here very much here in upprt PA.  STC vmp would be 95VMP with 3.37% voltage drop3.18. My configurazion  2 string =3 180watt schuco  1 string  2  180 watt schuco
               1 185w kyocera                        2  175 watt mitsubishi  These 3 strings have the same VMP of 82.2 v at warmest temp of 95 F.   STC at 77f 96.2VDC and 2160w for all 12 panels. highest VOC @ -26f 144volt. I think this would charge somewhere about 75 amp for a 24 volt system. under ideal conditions. Since I am already retired I am going to stay with the 24 volt system. Inverters have never been used and probably will last as long as I do. Havn,t decided on what to use for batterys yet for sure till I price them. Was thinking of a fork truck battery depending on the cost. More leaning on a set of 4 L 16 crown or US battery. The last time I talked with them they didn,t want the old ones. Crown said they would Give A $3.00 trade in.  ;Dsolarvic