Please help see if this system is okay

2

Comments

  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    @solarking the Gorilla fan suggestion is GREAT and it seems they only use 28w vs 65 or 75 ceiling fans. I will buy one right away to check how it performs and if people are happy with it why not I may replace all 7 of the current fans and bring down like 200watts 
  • solarking
    solarking Registered Users Posts: 67 ✭✭
    edited May 2017 #33
    Nila said:
    solarking said:
    Nila said:
    They are seemingly buying from China , however they do provide support + the warranty ,

    705$ inverter works out to 1100 when it is in your hand if you add customs + shipping and has no real support /warranty.

    I considered buying it from AliExpress but then decided against as if I have to return ship due to any issues , the time / money lost is already more than the difference.


    $705(INR45,526.00) is not aliexpress price
    http://www.amazon.in/Solar-Inverter-5KVA-High-Frequency/dp/B072P1VL1W



    @Solarking do you know where can I get some decent combiner box with the DC Fuse so I can parallel the strings from panel?
    Instead of using heavy gauge wire and an outdoor combiner box, you could use low gauge wire for each series string and combine it using dc MCB and on the other side of the mcb use heavy gauge wire which goes to MPPT.
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    solarking said:
    Nila said:
    solarking said:
    Nila said:
    They are seemingly buying from China , however they do provide support + the warranty ,

    705$ inverter works out to 1100 when it is in your hand if you add customs + shipping and has no real support /warranty.

    I considered buying it from AliExpress but then decided against as if I have to return ship due to any issues , the time / money lost is already more than the difference.


    $705(INR45,526.00) is not aliexpress price
    http://www.amazon.in/Solar-Inverter-5KVA-High-Frequency/dp/B072P1VL1W



    @Solarking do you know where can I get some decent combiner box with the DC Fuse so I can parallel the strings from panel?
    Instead of using heavy gauge wire and an outdoor combiner box, you could use low gauge wire for each series string and combine it using dc MCB before connecting to the PV input and on the other side of the mcb use heavy gauge wire.
    @solarking Man you are full of useful information, Should have let you design my system from the start - haha
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    @solarking  the DC MCB that will combine the outputs or should we manually use a bus bar or whatever to combine the other end before taking out the heavy gauge?

    Do you have a product link that you can share?
  • solarking
    solarking Registered Users Posts: 67 ✭✭
    Nila said:
    @solarking  the DC MCB that will combine the outputs or should we manually use a bus bar or whatever to combine the other end before taking out the heavy gauge?

    Do you have a product link that you can share?
    No bus bar needed just screw the wires in the mcb in and connect a heavy guage wire on the mcb out. If you are going to buy the Flinslim inverter the DC MCB is available with them. I have seen it on their ebay store but it was a long while ago. You are a Godfather in this field I am just a noob.
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    So you mean MCB has interconnections on one end of the POLE looking at the pics here it seems like the 3/4 pole mcbs just act as 4 separate ones I will continue to look into the spec sheets if i can find.

    Flin seems to be reselling the  FEEO they are actively selling direct on amazon so thats good
    http://www.feeo-solar.com/dc-circuit-breaker/dc-mcb/


  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    Looks like you are right .


  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    @Solarking ,

    Still looking at the available panels and most likely I would go with something like this
    • Pmax: 250 W, Voltage Vmax(V): 30.9 V, Current Imax (A): 8.09 A  
    • Each string will have 3 of those 
    So the Max current is 8A, and I would have like 3 strings (now & maybe 1 more in future) to parallel now still unsure how to connect those with the DC MCB & which one to choose i.e 3p or 4p ,etc.

    Which DC MDB Amperage rating should I look for in this setup?


  • solarking
    solarking Registered Users Posts: 67 ✭✭
    edited May 2017 #40
    Nila said:
    @Solarking ,

    Still looking at the available panels and most likely I would go with something like this
    • Pmax: 250 W, Voltage Vmax(V): 30.9 V, Current Imax (A): 8.09 A  
    • Each string will have 3 of those 
    So the Max current is 8A, and I would have like 3 strings (now & maybe 1 more in future) to parallel now still unsure how to connect those with the DC MCB & which one to choose i.e 3p or 4p ,etc.

    Which DC MDB Amperage rating should I look for in this setup?


    You will need 2 mcb one for the pv input and 1 in between  controller and  battery. Use 2pole  63a dc mcb or the one recommended by flinslim, it is available online or at any electrical shop. You can buy schneider dc breakers.
    http://www.amazon.in/GM-DC63-Double-Type-C-White/dp/B01G8NRCEY/
    http://www.amazon.in/Schneider-Solar-A9N61539-TWO-POLE/dp/B01780VA7G

    I know you are an experienced person in this field why would you ask basic questions.
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    HI @solarking

    Sorry to be a pain, to be honest I am more of an IT guy and Solar used to be one of our business a few years ago but I no longer do that.
    Now this is more of a hobby / interest and not really a job.

    Reason I am confused here is that usually I go with combiner box where I will have a DC Fuse for each Positive end of the string and the combiner will have this busbar that connects all the strings to one and then I will have a wire from there to the charge controller.

    So was confused on how to replace this setup with DC MCB 

    If I go with MCB, I will have two terminals available to screw the wires , will I have to connect ALL 3 wires from the panels (+) to one terminal of the MCB & all 3 wires from the (-) to the other & take the higher gauge wires from the other end to the controller.

  • solarking
    solarking Registered Users Posts: 67 ✭✭
    edited May 2017 #42
    Nila said:
    HI @solarking

    Sorry to be a pain, to be honest I am more of an IT guy and Solar used to be one of our business a few years ago but I no longer do that.
    Now this is more of a hobby / interest and not really a job.

    Reason I am confused here is that usually I go with combiner box where I will have a DC Fuse for each Positive end of the string and the combiner will have this busbar that connects all the strings to one and then I will have a wire from there to the charge controller.

    So was confused on how to replace this setup with DC MCB 

    If I go with MCB, I will have two terminals available to screw the wires , will I have to connect ALL 3 wires from the panels (+) to one terminal of the MCB & all 3 wires from the (-) to the other & take the higher gauge wires from the other end to the controller.

      I didn't intend to offend you, I was just curious. I am from Sivakasi.
    You don't need a fuse/mcb for each panel in the series string but you have to confirm this from senior members.
    Yes you have to connect the 3 positive from each series string to one pole and 3 negative to the other pole, on mcb out you have to connect 10sqmm which will be the PV input. On the inverter manual  right size dc mcb is mentioned I have read it long time back but you can try that.

  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    I m pretty sure that is a bad idea & you may need a FUSE or MCB for each string but I will wait for someone to confirm.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Generally, with modern solar panels, if you have two or one series strings, you do not need a combiner box with fuss/breakers. As an example, the Isc rating of 8 amps and a series fuse rating of 15 amps.

    You have two strings, and short one out (broken panel, mouse chewed through wiring which shorted to ground)--Isc from the one good string feeding a shorted string with a fuse rating of 15 amps will never trip the fuse.

    Now same thing with 3 strings. You have 2x8a=16 amps feeding a shorted panel with a 15 amp fuse/breaker. Now the over current protective device will trip (eventually, barely). Just on the "ragged edge" of needing protect fuse/breaker with 3 parallel connected strings.

    There are advantages to installing circuit breakers even with one and two string arrays--It is nice to use the breaker as an on/off switch for debugging and shutting down power when working on your system.

    Note that "touch safe" fuse holders cannot be used as switches--they can arc and catch fire if the fuse i popped out when under load.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    Hi BB

    That makes perfect sense.,

    So for a 3 or 4 strings array that has voc of (37*3) & 8 Amps and at this power rating do you think it is okay to just use a MCB and screw three of these strings to one end and have it both 'parallel/combine' the string and also act as a switch ?

    I dont see this setup protecting againts the shorted string issue but only acts as a switch please correct me if im wrong

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Yes, probably a 15 amp breaker per string.

    The breakers are to protect a single shorted string.

    The breakers are not there to protect against a, for example, shorted main run from combiner box to the charge controller (a shorted array will not supply enough current to trip all the breakers).

    Instead, the main run cable is heavy enough to carry Isc-array without over heating the cable.

    - Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • solarking
    solarking Registered Users Posts: 67 ✭✭
    BB. said:
    Yes, probably a 15 amp breaker per string.

    The breakers are to protect a single shorted string.

    The breakers are not there to protect against a, for example, shorted main run from combiner box to the charge controller (a shorted array will not supply enough current to trip all the breakers).

    Instead, the main run cable is heavy enough to carry Isc-array without over heating the cable.

    - Bill
    For eg. if 2 24v panels is connected in series and 2 such strings are connected in parallel where should we place breaker and what amps breaker will be suitable?
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    For two strings, you don't really need breakers. As Bill explained, they should never trip with two strings.

    They are handy as disconnects though. They would normally go on the positive wire from each series string in the combiner box before the parallel connection.

    Panel specs should list max breaker size, often 15a.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • solarking
    solarking Registered Users Posts: 67 ✭✭
    edited June 2017 #49

    Nila,

    If you are really serious about the grid tie setup, you should choose a stand alone grid tie inverter and use a separate inverter/battery setup coz it will be much more reliable. If you really like playing with your solar setup then offgrid setup will be more fun. Flinsin is a high frequency inverter so you will need some kind of protection for this inverter like isolation transformer or stabilizer. What panel do you intend to use?What is the cheapest price per watt you got as quote?

  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    edited June 2017 #50
    Hi @solarking

    1. I am not serious about grid tie I am only adding 2.25KW panels total on t his setup 

    The availability & possibility of adding a "net meter" is going to be a huge pain in our local grid.

    2. I went with off grid with sukaam inverter earlier and only lost all batteries in the process so I want to keep this hybrid and not drain batteries unnecessarily

    3. When you said protection for the inverter you believe I should add a stabilizer before the inverter? I will look into that as I am serious about safety.

    4. Panels still looking I am getting quotes from 40-45 rupees per watt, in the past I was able to get it for 35 i cant find such pricing now.

    5. I am thinking about a LARGE string inverter GT setup for my office at year end, so may do it that way there possibly upto 8KW 
  • solarking
    solarking Registered Users Posts: 67 ✭✭
    edited June 2017 #51
    Hi @Nila

    Have you checked this site solarkart.ezysolare.com. You can contact the solar manufacturers directly and they will give you much lesser quote , if you are lucky you can get it below 35. Solar is my hobby.
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    edited June 2017 #52
    Thank you and you just saved me like 6-8rs/watt and that's nearly 2250*7 rupees which is a big favor, I am contacting some companies via easysolare so 

    HHV250wp
    15.041650 x 987 x 4210 years
    Sova Solar250wp15.531639 X 982 X 4212 years
    Navitas250wp
    15.481639 X 989 X 4010 YEARS
    PV Powertech250wp
    15.351639 X 989 X 3510 YEARS
    Out of these 4 whom you believe is the best bet for us in south most india.

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    edited June 2017 #53
    Is that a 10 year warranty? That may be what the market supports in your region.

    Watch the panel cell material/construction... I am not a fan of "thin film" panels, or panels made with other than glass face (various clear plastics).

    I believe in general fixed applications, that glass panels with Mono and Poly Crystalline cells are the most reliable/longest lasting. In the US, you will generally get 20-25 year warranties (will the companies be around for 20-25 years--that is an open question).
     
    Panels are getting cheap enough for the consumer to "own the warranty costs". Paying $10 USD per Watt with a 25 year warranty vs $1 USD per Watt and a 10 year warranty--The lower cost panels make more economic sense.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    HI BB, Yeah the costs is so low I do not care about warranties at this point, Just looking for the most big company here so there is less chance of them closing shop before 10 years lol.. and @solarking is just 100miles from me so he probably has an idea.

    Not sure how it compares to the USA though we are talking about 0.5 or 0.6 $ / watt here :) 

    Regarding the combiner box, I asked someone to set that up with 3 DC MCB 10A  , 250VDC rated from Schnider (10$ each) and I will use a bus bar to combine the strings.


  • solarking
    solarking Registered Users Posts: 67 ✭✭
    edited June 2017 #55


    Nila said:
    Thank you and you just saved me like 6-8rs/watt and that's nearly 2250*7 rupees which is a big favor, I am contacting some companies via easysolare so 

    HHV250wp
    15.041650 x 987 x 4210 years
    Sova Solar250wp
    15.531639 X 982 X 4212 years
    Navitas250wp
    15.481639 X 989 X 4010 YEARS
    PV Powertech250wp
    15.351639 X 989 X 3510 YEARS
    Out of these 4 whom you believe is the best bet for us in south most india.

    Hi @Nila

    Based on the mw installed

    hhv 100mw installed
    sova solar 100mw installed
    navitas 75 mw installed
    pv powertech 50mw installed

    I am not sure if it is right to choose based on the mw installed, almost all them appears to be good choose someone who quotes low

    you may also go through the list and shortlist few of them based on  mw installed and send a mail and negotiate. 

     http://mnre.gov.in/file-manager/UserFiles/information-sought-from-all-Solar-Cell-&-Module-manufacturers.pdf
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Yea, we can get to a bit below $0.60 per Watt from our host NAWS:

    https://www.solar-electric.com/residential/solar-panels.html
    Watts/Name-Model/$ per module/Qty 1 pricing/Q20 pricing
    190 Topoint Solar JTM 190-72M$162.50$0.855 $0.78
    265Kyocera KU265-6MCA$167.00$0.63 $0.62
    270 Kyocera KU270-6MCA$195.00$0.722 $0.65
    280 REC 280W All Black TwinPeak2$165.20$0.59 
    285 SolarWorld SW-285 Mono 4.0$310.00$1.088 
    285 SolarWorld SW-285 Mono Black$225.15$0.79 
    290 REC 290W TwinPeak2$162.40$0.56 
    290 REC 290W Black TwinPeak2$162.40$0.56 
    295 SolarWorld SW 295 Mono Black$243.00$0.824 $0.841
    300 SolarWorld SW-300 Mono$291.00$0.97 
    315 LG 315 Watt Mono$367.00$1.165 
    335 REC 335 Watt Poly 72 Cell$204.35$0.61 
    335 LG 335 Watt Mono 72 Cell$361.80$1.08 
    340 Kyocera KU340-8BCA$214.20$0.63 
    345SolarWorld XL 345$307.05$0.89 

    -Bill


    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    @Solarking THANK you again I will prob go with HHV that is good because pricing is more or less same but it is the closest.

    and @BB this is good to know we are paying close to USA rates for the panel because generally for Electronics we will pay a premium of atleast 20% to sometimes 200% due to our customs/shipping costs.

    Looking at the cost of the panels & the grid costs in the USA generally surprises me how people do not go for GT setup as much as they should, the cost can be recovered quicker than say India where the grid costs are low and hence longer time before we can recoup the benefits.



  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    @Nila

    A few years ago there was a bit of a "gold rush" on grid connected solar. Some places (eg Ontario Canada) had very attractive feed-in tariffs (up to $0.80/kwh IIRC) on long term contracts.

    The problem is the grid infrastructure couldn't physically handle more than token amounts of randomly placed solar. Additionally, the added subsidized capacity tended to strand sunk costs in conventional generation.

    The upshot of all this is many jurisdictions have radically reduced incentives, and some actively discourage new small scale grid-tie. I just read today about one that taxes supply from grid, but doesn't rebate on supply to grid. Some have rejigged rate structures so consumption itself makes up a relatively small part of the price, fixed service and delivery making up a significant part

    In my city house, the government fairly recently introduced a (politically motivated) $1/watt subsidy. Even with the subsidy though, it still doesn't make $ sense to do grid tie unless you really torture the assumptions and numbers.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    Thanks @Estragon for that information.

    And others I have ordered the panels now have to look into getting it installed in ten days or so.

    First I will setup just the inverter/batteries to see if it's stable and kicking before going ahead on the solar part.
  • solarking
    solarking Registered Users Posts: 67 ✭✭
    Nila said:
    Thanks @Estragon for that information.

    And others I have ordered the panels now have to look into getting it installed in ten days or so.

    First I will setup just the inverter/batteries to see if it's stable and kicking before going ahead on the solar part.

    How many panels did you order and what is the final quote?
  • Nila
    Nila Solar Expert Posts: 173 ✭✭
    @Solarking,

    I ordered 9x250 and total with freight came upto 75375 INR