installing 9 panels

Hi everyone, i purchased 9 sonali panels
36.6 vmp
7.84 imp
36.6 voc
8.3 isc

I was wondering how i should i wire them to a mppt 50? also i currently using a 24 v outback inverter but i will update to 48 v as soon as i can get my 8
L16H batteries out of customs.
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Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: installing 9 panels

    an mppt 50? do you mean a blue sky mppt 50? if so then you've got a problem with going to 48v as the controller can't handle that high of an input voltage the last i saw. if you mean a mppt cc that can handle higher voltages then the pv wiring isn't so difficult. it appears by the vmp that a single pv is able to handle a 24v battery bank. for 48v just put another pv in series for a string of 2. now some of the mppt controllers can even handle 3 of those pvs in series. with 9 of the pvs obtained then something like a midnite classic for example would work well as it would be 3 strings of 3 in series. the fm60 and tristar mppt 45 and 60 model ccs would also work otherwise you may need to add or subtract a pv from your proposed 48v system.
  • YehoshuaAgapao
    YehoshuaAgapao Solar Expert Posts: 280 ✭✭
    Re: installing 9 panels

    The BlueSky SolarBoost MPPT 50 are step-up charge controllers, upconverting lower panel voltages to bettery voltage. They accept maximum 32V (24V battery) and work with 12 or 24V battery banks. Also being a step-up converter, they are only MPPT only if solar voltage is below battery voltage. If solar voltage is above battery voltage, it behaves more like a conventional PWM controller.

    You got 72-cell panels. Not a very good fit for 150V MPPT controllers. 3 to a string will overvoltage in cold weather (particularly at dawn), 2 to a string will frequently undervoltage on a 48-volt battery bank. Midnite solar MPPT controllers are more flexible than the rest, so you are probably better of getting one of those to use with 72-cell panels.

    60-cell polycrystalline panels are perfect in strings of 3. 96-cell for strings of 2. 48-cell strings of 4, 36-cell strings of 5. 54-cell, 72-cell, 80-cell are not very good fits. This is for polycrystalline panels. Monocrystalline is different - more volts per cell.

    Also Xantrex and BlueSky controllers do not support common / shared negatives with other controllers (if you have multiple).
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    sorry i meant a Morningstar TS-MPPT-60.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: installing 9 panels

    in looking back i need a correction from you as i see the vmp and voc as at the same voltage. one of them is wrong. which one?

    also say if you are in anyway subject to cold temps for if you are in a hot area that never gets anywhere near freezing then i don't think the voltages on the voc will stray very much higher than stated voc. if it's very close to the cc max then rethink either the pvs or cc.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: installing 9 panels

    nevermind as i found it and they committed the error.
    http://www.sonalisolar.com/ss-230-240-250-series.php
    most likely by extrapolation the vmp is 30.6v and the voc is 36.6v. this changes things as these are 60 celled pvs and not 72 celled pvs. you will need 2 in series for 24v battery banks rather than 1 and you need to go 3 in series for 48v battery banks. the mppt 60 should do fine for all 9 pvs in a 3x3 arrangement for 48v batteries. now you won't be able to utilize all of the power of all 9 pvs in a 24v battery bank as the 60a limit x 24v = 1440w capacity and your pvs are 240w each x 9 for 2160w. you max the cc for 48v at 60a x 48v = 2880w.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: installing 9 panels
    Also Xantrex and BlueSky controllers do not support common / shared negatives with other controllers (if you have multiple).

    What happens if you mix a Xantrex controller with a Midnite or Outback controller? (Midnite and Outback have common Bat negative and PV negative).

    I can think of a few forum members who have mixed these controllers, I don't recall reading about any problems.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    vtmaps wrote: »
    What happens if you mix a Xantrex controller with a Midnite or Outback controller? (Midnite and Outback have common Bat negative and PV negative).

    I can think of a few forum members who have mixed these controllers, I don't recall reading about any problems.

    --vtMaps

    He means "common both sides" as the Xantrex & Blue Sky do some measuring on the PV negative whereas most controllers don't. Common output is not a problem, but if the negative IN and negative OUT are shorted on these controllers they won't work right.
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    to get the full power out of these panels, should i look into getting another charge controller? Im in Ky right now but will be heading back to Haiti in 2 weeks to start setting it up. also if there a economical/easy way of installing these on a slated steel roof?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    castilloj wrote: »
    to get the full power out of these panels, should i look into getting another charge controller? Im in Ky right now but will be heading back to Haiti in 2 weeks to start setting it up. also if there a economical/easy way of installing these on a slated steel roof?

    Not worth it. Largest controllers available are 80 Amps: 80 * 24 = 1920 Watts and you've got 2160. Using standard derating you'd get 68 Amps @ 24 Volts. The bigger controller would put out more (and for longer as it could be peaked with less than full insolation), but once you update to 48 Volts it won't matter anymore.

    About that: you have eight L16's coming. Of what Amp hour capacity? They tend to run 320-390-ish. With the full array @ 48 Volts you'll have about 34 Amps of current available.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: installing 9 panels
    --vtMaps He means "common both sides" as the Xantrex & Blue Sky do some measuring on the PV negative whereas most controllers don't. Common output is not a problem, but if the negative IN and negative OUT are shorted on these controllers they won't work right.

    OK, I see. So on the Xantrex & Blue Sky controllers the PV input has to be floating. Does that mean no GFP devices on the PV input? Does that mean both PV pos and PV neg should be fused?

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    right now im using 4 L16 335ah and the ones that im still waiting for are the L16H 435ah
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    vtmaps wrote: »
    OK, I see. So on the Xantrex & Blue Sky controllers the PV input has to be floating. Does that mean no GFP devices on the PV input? Does that mean both PV pos and PV neg should be fused?

    --vtMaps

    Good questions.
    GFDCI actually requires the PV to be 'floating' as it checks for current flow between negative and ground and then trips out positive if it is detected. As such a single breaker can be used on the positive line only at least for low Voltage arrays. There is little danger from them in any case.

    I don't think NEC requires double pole common trip on PV, but Canada tends to lag behind on these things anyway. :p

    For these particular controllers the important thing is that (-) in and (-) out not be connected. This would not happen most of the time, but if you had two arrays for two different controllers and brought the arrays to a common box for disconnect it would be very easy and even likely to have the negatives of both arrays connect on a bus bar there. That means the (-) input on, say, a Xantrex would then be in common with the (-) input on, say, an Outback. Since the outputs would be common for both (-) and (+) the Outback would then create a short around the Xantrex's (-) in and (-) out.

    Complicated, isn't it?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    castilloj wrote: »
    right now im using 4 L16 335ah and the ones that im still waiting for are the L16H 435ah


    Ah, so 34 Amps on a 435 Amp hour bank. 7.8% peak charge rate. That is a tad on the low side. Any chance of getting three more of these panels and boosting that current up around 45 Amps?
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    I may be able to , but it may take a long time. but could i use any of my older pw1000 panels to make up the remaining amperage?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    castilloj wrote: »
    I may be able to , but it may take a long time. but could i use any of my older pw1000 panels to make up the remaining amperage?

    That would depend on the specs of those panels. Chances are you couldn't make up a string of them that would exactly match for paralleling to the others, which would leave you with putting them on a separate controller.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: installing 9 panels

    if indeed he has 240w pvs. as i suspect, he would be right at the max operational point for the cc with 3 more pvs, but he should be fine in the mean time with what he has, providing if the pvs produce more than what the loads have drawn out.
  • YehoshuaAgapao
    YehoshuaAgapao Solar Expert Posts: 280 ✭✭
    Re: installing 9 panels
    Ah, so 34 Amps on a 435 Amp hour bank. 7.8% peak charge rate. That is a tad on the low side. Any chance of getting three more of these panels and boosting that current up around 45 Amps?

    12 60-cell polycrystalline panels per string of L16 batteries are a very nice fit and will fully utilize the charge controller without chronic maxxing.

    24 Volt Single Charge Controller Systems
    #PV     StrSize #PVStr  PV Watts    PV KWh/day  BatVolt #MPPT CC    Inverter (Min)      Batteries           #BatStr BattAH  BattKWh PV Charge Rate
    2       2       1       450-520     2.250-2.600 24      1 (20A)     600W Pure Sine      2x Group 31         1       130     3.12    9.35-10.81 hrs - Nominal
    3       3       1       675-780     3.375-3.900 24      1 (30A)     1000W Pure Sine     4x Golf Cart GC2    1       225     5.4     10.79-12.47 hrs - Low-Nominal
    3       3       1       675-780     3.375-3.900 24      1 (30A)     1000W Pure Sine     4x Group 31         2       260     6.24    12.46-14.41 hrs - Low
    4       2       2       900-1040    4.500-5.200 24      1 (45A)     1000W Pure Sine     4x Golf Cart GC2    1       225     5.4     8.09-9.35 hrs - Near Cost Effective Maximum
    6       2 or 3  3 or 2  1350-1560   6.750-7.800 24      1 (60A)     Outback FX/VFX      4x L16              1       400     9.6     9.59-11.08 hrs - Nominal
    6       2 or 3  3 or 2  1350-1560   6.750-7.800 24      1 (60A)     Outback FX/VFX      8x Golf Cart GC2    2       450     10.8    10.79-12.47 hrs - Low-Nominal
    8       2       4       1800-2080   9.00-10.400 24      1 (80A)     Outback FX/VFX      4x L16              1       400     9.6     7.19-8.31 hrs - At Cost Effective Maximum
    8       2       4       1800-2080   9.00-10.400 24      1 (80A)     Outback FX/VFX      8x Golf Cart GC2    2       450     10.8    8.09-9.35 hrs - Near Cost Effective Maximum
    

    48 Volt Single Charge Controller Systems
    #PV     StrSize #PVStr  PV Watts    PV KWh/day  BatVolt #MPPT CC    Inverter (Min)      Batteries           #BatStr BattAH  BattKWh PV Charge Rate
    3       3       1       675-780     3.375-3.900 48      1 (15A)     1000W Pure Sine     4x Group 31         1       130     6.24    12.46-14.41 hrs - Low
    6       3       2       1350-1560   3.375-3.900 48      1 (30A)     Outback FX/VFX      8x Golf Cart GC2    1       225     10.8    10.79-12.47 hrs - Low-Nominal
    6       3       2       1350-1560   6.750-7.800 48      1 (30A)     Outback FX/VFX      8x Group 31         2       260     12.48   12.46-14.41 hrs - Low
    9       3       3       2025-2340   10.125-11.7 48      1 (45A)     Outback FX/VFX      8x Golf Cart GC2    1       225     10.8    7.19-8.31 hrs - At Cost Effective Maximum
    9       3       3       2025-2340   10.125-11.7 48      1 (45A)     Outback FX/VFX      8x Group 31         2       260     12.48   8.31-9.60 hrs - Near Cost Effective Maximum
    12      3       4       2700-3120   13.50-15.60 48      1 (60A)     Outback FX/VFX      8x L16              1       400     19.2    9.59-11.08 hrs - Nominal
    12      3       4       2700-3120   13.50-15.60 48      1 (60A)     Outback FX/VFX      16x Golf Cart GC2   2       450     21.6    10.79-12.47 hrs - Low-Nominal
    15      3       5       3375-3900   16.875-19.5 48      1 (80A)     Outback VFX         8x L16              1       400     19.2    7.67-8.87 hrs - At Cost Effective Maximum
    15      3       5       3375-3900   16.875-19.5 48      1 (80A)     Outback VFX         16x Golf Cart GC2   2       450     21.6    8.63-9.97 hrs - Near Cost Effective Maximum
    
  • arby
    arby Solar Expert Posts: 107 ✭✭
    Re: installing 9 panels
    castilloj wrote: »
    Hi everyone, i purchased 9 sonali panels
    36.6 vmp
    7.84 imp
    36.6 voc
    8.3 isc

    I was wondering how i should i wire them to a mppt 50? also i currently using a 24 v outback inverter but i will update to 48 v as soon as i can get my 8
    L16H batteries out of customs.

    "Maximum Solar Array Size 12 VDC systems 800 Watts / 24 VDC systems 1600 Watts / 48 VDC systems 3200 Watts "

    found here---

    http://www.enviroharvest.ca/outback_controller.htm
    3310 watts panels, Classic 200 controller, 8 Surette S530's, Xantrex 5548 inverter, Honda EX5500 backup Genny.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: installing 9 panels
    arby wrote: »
    "Maximum Solar Array Size 12 VDC systems 800 Watts / 24 VDC systems 1600 Watts / 48 VDC systems 3200 Watts "

    found here---

    http://www.enviroharvest.ca/outback_controller.htm

    i'm not sure just how they come up with figures like that and nobody ever explained it to me as 800w/12v=66.67a on a 60a cc. safer to go by the voltage x the cc current capability or 12v x 60a = 720w.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels

    Which OB controller? The 60 Amp MX60 (which can actually got to 70 Amps), the 60 Amp FM60 or the 80 Amp FM80?

    Besides which you can put more array on than you actually need (within reason) so that the controller can have peak current to work with more often.

    For example:
    60 Amps maximum current * 12 Volts minimum / 0.77 derating factor = 935 Watt array.
  • SandyP
    SandyP Solar Expert Posts: 65 ✭✭
    Re: installing 9 panels
    Besides which you can put more array on than you actually need (within reason) so that the controller can have peak current to work with more often.

    I am wondering, how far is "within reason"?

    On days of higher power usage, we already see our FM60 exceed the 60amp rating (based on the FM60's 'Ap' record) however, I am unsure how long this >60amp event occurs.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    SandyP wrote: »
    I am wondering, how far is "within reason"?

    On days of higher power usage, we already see our FM60 exceed the 60amp rating (based on the FM60's 'Ap' record) however, I am unsure how long this >60amp event occurs.

    "Within reason" would be up to the point where you're just buying a lot of panel for nothing.

    You can program the FM60 to limit current to less than its full potential too. As such you could have twice the typical amount of array to provide charging under poor conditions and keep the charge rate from going too high on sunny days. Most installations will not do this as it is a waste of panel for a large portion of the year; a generator is cheaper.

    With 620 Amp hours of battery you probably should have opted for the FM80 and gone for two more of those 190 Watt panels. As it is, you're doing good!
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    hey guys, i also wondered about wiring these, i was thinking about ordering a 100 ft roll of pv wire and also a crimper to make my own connections, what do you guys think about that? this is my first time dealing with MC4 connectors.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: installing 9 panels

    most of us buy a small mc4 extension and cut it in half and then splice the type and gauge of wire we choose. with small runs you could just use the extensions without cutting and splicing if the wire gauge they use isn't objectionable.
  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: installing 9 panels
    castilloj wrote: »
    hey guys, i also wondered about wiring these, i was thinking about ordering a 100 ft roll of pv wire and also a crimper to make my own connections, what do you guys think about that? this is my first time dealing with MC4 connectors.

    For my system, it was cheaper to buy MC4 extensions and cut them in halves. I needed 8 of them.
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    so if im wiring 9 panels. 3 sets of 3 in series for 24 v system. i should buy 6 25 ft pv connectors, then cut them in half and splice them with 10 awg wire?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    castilloj wrote: »
    so if im wiring 9 panels. 3 sets of 3 in series for 24 v system. i should buy 6 25 ft pv connectors, then cut them in half and splice them with 10 awg wire?

    No, you only need one MC4 extension per string: cut in half it gives you a connector for the positive side and one for the negative side as well. They wouldn't need to be 25 feet either, as you are only after getting the pre-crimped ends to create "pig tails" for connecting to conventional wire.
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    Hi guys, sorry for bringing this thread back. i haven't been able to get 8 batteries. I still only use 4, Should i go ahead and wire the Sonali Panels 2 in series and just not use the 9th?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: installing 9 panels
    castilloj wrote: »
    Hi guys, sorry for bringing this thread back. i haven't been able to get 8 batteries. I still only use 4, Should i go ahead and wire the Sonali Panels 2 in series and just not use the 9th?

    Nice thing about an MPPT charge controller; input Voltage does not have to 'match' output Voltage.

    If you are planning on upping the system Voltage, go ahead and wire it for three strings of three. Slight loss in conversion efficiency now will more than be made up for by not having to rewire the array later.
  • castilloj
    castilloj Solar Expert Posts: 208
    Re: installing 9 panels

    what voltage should i get from one string of 3?