New system hook up question

Hope some of you can help point me in the correct direction. I started out with 2- 1500 watt / 24volt turbines. Thinking wth the winds I get I should get 200 to 400 watts out of the turbines almost all the time. Not happening, I think these turbines are not what they made them out to be. OK, so I decide to add 6 - 200 watt 12 volt Evergreen solar panel to the system.

My system:

Control Panel 440amp 10,000 watt (12, 24, or 48 volt)

Inverters: Power Bright 2300watt / 12 volt (refrigerator & freezer)
Statpower 700 watt / 12 volt (40 watt LED lighting and laptop)

Turbines: 2 - 1500 watt / 24 volt Missouri Wind and Solar (I know I got taken)

Solar Panels: 6 - 200 watt / 12 volt Evergreen

Batteries: 8 - 6 volt 210 ah connected in series/parallel to give me 12 volt 840ah

I have 2 sets of 3 - 200 watt/12 volt panels connected parallel to a 10 gauge running 18 feet from roof to Control Panel.

I have 10 gauge wire 6 feet running from control panel to batteries for charging

I have 2 gauge wire connecting each battery to each other and 2 gauge wire from batteries to 2300 watt inverter (6 feet) and 10 gauge wire from battery to 700 watt inverter (6 feet).

Question is, is this a good setup or does anyone have some suggestion to my setup?

Comments

  • nsaspooknsaspook Posts: 396Solar Expert ✭✭✭
    Re: New system hook up question

    You should look at your wiring interconnect sizes if everything is 12vdc.

    Your 10 gauge interconnect wires are eating up power, even the 2 gauge for battery/inverter connections is under sized for full power.

    http://wiki.xtronics.com/index.php/Wire-Gauge_Ampacity
  • BB.BB. Posts: 27,925Super Moderators, Administrators admin
    Re: New system hook up question

    Also, the 440 Amp Control panel is, I assume, a "dump" load controller for the wind turbine.

    And while that is fine for wind turbines, an actual Solar Charge Controller (probably a MPPT type) would be better in the long term... Both for better charging current and better battery charging overall (dump controllers are very course type charging control and the batteries may not last as long/charge as well).

    Especially with a 12 volt battery bank, you should look at also reducing the cabling length between the inverters, charge controller, and the battery bank.

    Also, you have a 12 volt battery bank and 2xVmp~17.5 volt Evergreen panels in series connected to your 12 volt battery bank via the 440 amp dump controller??? If you are using two Evergreens in series, then you are loosing about 1/2 of their output power.

    Probably not a good idea. I would suggest that you give us the details (series/parallel, which model Evergreen panels and their Imp/Vmp ratings), and how long each of the wire runs is...

    Also, have you worked out your daily Watt*Hour (or Amp*Hour) power needs?

    And have you been monitoring your battery bank state of charge (hydrometer or battery meter)? Do you have backup grid power or genset to keep them properly charged? It is very common for people to accidentally run down a battery bank if they are not watching it closely for State of Charge -- Especially when there are other problems (like your wind system not working correctly) and permanently damaging their battery bank..

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490mike95490 Posts: 7,922Solar Expert ✭✭✭✭
    Re: New system hook up question

    You should have your panels connected through a solar PV charge controller.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • System2System2 Posts: 6,290 admin
    Re: New system hook up question

    If I understand your description, then you have all those panels connected to one 10 ga cable. Each panel should have its own 12 ga or larger cable to the controller; don't gather them together prior to reaching the controller. If all those panels are actually trying to feed the controller through one 10 ga cable, that's a major problem for current flow.

    For our systems, we use a 12 ga cable and separate controller for each 120 watt panel. These all come to a junction block where the current is gathered and put into the battery bank via a 1/0 copper cable. Voltage loss for DC is pretty nasty, and requires lots of big cables to defeat.

    You can use as many controllers as you want, all connected to the same battery bank; our SG-1 is indefinitely expandable with as many panels and batteries as you care to attach.
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: New system hook up question
    If I understand your description, then you have all those panels connected to one 10 ga cable. Each panel should have its own 12 ga or larger cable to the controller; don't gather them together prior to reaching the controller. If all those panels are actually trying to feed the controller through one 10 ga cable, that's a major problem for current flow.

    For our systems, we use a 12 ga cable and separate controller for each 120 watt panel. These all come to a junction block where the current is gathered and put into the battery bank via a 1/0 copper cable. Voltage loss for DC is pretty nasty, and requires lots of big cables to defeat.

    You can use as many controllers as you want, all connected to the same battery bank; our SG-1 is indefinitely expandable with as many panels and batteries as you care to attach.

    :confused:
    Why would you need 12 AWG wire to carry less than 8 Amps maximum? How long are these wire runs?
    I'm glad you're not spending my money.
  • mtfalk64mtfalk64 Posts: 6Registered Users
    Re: New system hook up question

    I do thank you all for your inputs. I know not everyone agree on some things and that is why I was asking.

    Yes the 440amp 10K charge controller is a dump controller too. I was told that this unit would handle both my wind turbine and solar. But I would take the advice more from you all then the sales BS from Missiour Wind and Solar.


    I do have three (3) 200 watt panels connected in parallel which is 12 volt and 600 watts on a 10 gauge wire that runs 18 feet to the controller.

    would it be ok to run 6 gauge wire for the three (3) 200 watt panel in parallel?

    Or are you all saying to just run each 200 watt panel using 12 or 10 gauge for the 18 foot to a separate charge controller. So I would end up with 6 charge controllers and six (6) cable of either 12 or 10 gauge that would be 18 foot long?

    if I get six (6) separate charge controllers then I only need 10a or 20a controllers?

    is there a charge controller for having six (6) 200 watt panel connected to one (1) controller or is everyone say to have six(6) charge controller?

    what is a good charge controller but at a good price? I am on a limited budget.
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: New system hook up question

    I'll just say this: MPPT is your friend for over 400 Watt arrays. Separate 12 gauge wire runs and separate charge controllers per panel is silly.
  • mtfalk64mtfalk64 Posts: 6Registered Users
    Re: New system hook up question

    I will agree that I am not going to buy six (6) separate charge controllers and keep adding a new charge controller every panel that I buy. I would like to know that if I buy a charge controller what amp controller should i be looking at with six (6) 200 watt panels?
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: New system hook up question

    Six 200 Watt panels = 1200 Watts. Factor by efficiency (typically 77% but can be better/worse) and divide by system charging Voltage and you'll get the potential peak Amperage:
    1200 * 0.77 = 924 / 14.2 (12 Volt system) = 65 Amps (big for a 12 Volt system; you're looking at an FM80 here).
    Same panels on a "24 Volt" system = 32.5 Amps. There you could go with a Morningstar Tristar 45 MPPT or any of the 60 Amp MPPT which may allow future expansion (if panels can be had within the same specs as originals).
    At 48 Volts you're down to roughly 16 Amps, and it may not be a worthwhile system design.
    Basically that size array is best suited for 24 Volts.

    The panel specs are probably along the lines of 18 Vmp and 11 Imp. Three in series would give a string of 54 Vmp (+/-) @ 11 Imp. Two of these strings in parallel would run 22 Amps at maximum power. Without doing the actual calculation (you can find the Voltage drop calculator here: http://forum.solar-electric.com/showthread.php?t=29) I'd say for an 18 foot run at that Voltage and current 10 AWG wire should be sufficient.
  • mtfalk64mtfalk64 Posts: 6Registered Users
    Re: New system hook up question

    thanks for the reply. Now is it possible to take the two (2) 12 volt panels in series to get 24v then run it to the MPPT and it will auto put it back to 12 volts to the batteries. Why I am ask you is that is what another person wrote on one of the amazon MPPT units. Here if you have a minute, this is what someone wrote on one of the controllers on amazon, what do you think of this:

    "A 16V, 30 watt panel might give you 33 watts at a particular voltage, or an extra 10% using MPPT. In other installations, wiring your panels in series for higher voltages may be where the maximum power is found. The chip inside the MPPT tracker searches for this peak in your system and operates the solar panel (or array of panels) at it's absolute maximum power, which is sent to the DC/DC converter to charge your batteries.

    We might get 10-30% more power doing this, but the voltage will be all wrong for charging our battery, or our battery array. And that's where the DC/DC converter steps in. As a simple example, say you find that 2 panels in parallel give you 14.5V at 1.9A going through your non-MPPT charge controller, or 27.5W delivered to your batteries. Wired in series using MPPT they give you 37V at 1.25A or ~48W. You would get more power by wiring in series for a higher solar voltage of 37V, which is too high to charge a 12V lead acid storage battery. Now you need a MPPT.

    The MPPT takes the 37V, 1.25A from your panels and gets ~48W, looses 2W in conversion inefficiencies(give or take) for 46W out, and converts it to 13.6V to charge your battery array at 3.38A [45.96W] whereas had you wired the two panels in parallel you would get about 27.5 watts in this illustration. "

    Now since I am new to solar, I have no idea if this really works or this person has no idea what they are talking about.
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: New system hook up question

    Yup.
    Maximum Power Point Tracking.
    It can indeed downconvert higher array Voltages to lower system Voltages. That's why I suggested the 3 panels in series x two such strings. Nominally the array Voltage would be 36, but in reality a "12 Volt" panel has a Voltage at Maximum Power (Vmp) of 17-18 Volts or so. Thus the actual array Voltage would be in the neighborhood of 52-54 Volts whereas the charge Voltage of the battery can be 14.2 (for "12 Volt" systems) or 28.4 (for "24 Volt" systems).

    Conversely, if you were to wire all these "12 Volt" panels in parallel and use a PWM type controller you'd need six fuses - one per panel - and wire sufficient to carry the full output from the array to the charge controller. That would be like 66 Amps @ 18 Volts. A need for much heavier wire to handle the current and greater potential Voltage drop with the lower Voltage. Off the top of my head you'd need about 4 AWG to handle that all in one go. A bad design choice any way you look at it.
  • mtfalk64mtfalk64 Posts: 6Registered Users
    Re: New system hook up question

    I can handle putting 3 panels in series which would allow me to use smaller gauge wire to controller. Now if i did that I could get away with two (2) 45amp mppt controllers or would you say I need two (2) 60 amp mppt controllers? Plus I would only be needing 12 or 10 gauge wire 18 foot long to the controllers with panels in series.
  • nielniel Posts: 10,311Solar Expert ✭✭✭✭
    Re: New system hook up question

    a few things here,
    not all mppt controllers downconvert and some have limits on not only the output current capacity, but especially the upper voltage limit the controller can tolerate and as such will prevent putting some pvs in series or very many of them unless you go with a better and higher priced controller.

    when you get 10% from mppt controllers, THIS IS NOT CREATING MORE POWER THAN THE PV HAS, and that would defy many natural laws of physics, electronics, etc. there is always a loss of power for the record. there are losses involved with standard pwm controllers and an mppt controller recovers some of that power thatwould've normally not been realized.
  • CariboocootCariboocoot Posts: 17,615Banned ✭✭
    Re: New system hook up question

    I must be throwing too much math at you. :p

    If you configure the array as two strings of three panels each and charge a 12 Volt system the maximum current would be approximately 65 Amps. There's only one controller that can handle that: the Outback FM80 (which is good up to 80 Amps). If you use a 60 Amp controller the output current will be limited to 60 Amps, regardless of panel production. Anything over that will be lost.

    As Niel said, even the best MPPT controllers have input limitations. That is why I mentioned the Outback and Tristar. They, along with the Midnight Classic and Xantrex units, can handle an input Voltage of 150 maximum (Midnight has models that can handle more and Xantrex is bringing out a very high Voltage unit).

    If you want to size this set up correctly, look at it this way:
    Daily Watt hour usage will determine the size of the battery bank. The size of the battery bank will tell you what you need in array Watts to recharge it and how big a charge controller is required to handle it.

    Were it me, working backwards from the array I'd either up the system Voltage to 24 or drop a couple of panels for 12. Buying two MPPT controllers is expensive just to squeeze out that last 5-10 Amps.

    But it really depends on your power needs.
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