Hows this system sound? wires and breakers.

micahvmicahv Registered Users Posts: 17
Here is what I got
Kyocera 205W
Morningstar Sunsaver MPPT (specified 25A fuse between CC and Battery)
Morningstar Suresine 300 (100A Bat. to Inverter Fuse, 3A AC output fuse specified)
2 6V Batteries running at 12V 2400Wh( I think)
Midnight Solar MiniDC Disconnect 125A main breaker.

I got it all hooked up in a temporary fashion but have some questions regarding wiring and fuses while trying to adhere to the manuals of said product. Also, just looking for comment...hopefully not to many responses in the tune of...call the fire dept. ASAP...I'm not leaving the AC side powered unattended.

---Grounding---
My DC grounding electrode is 4# stranded copper running from the Grounding Bus bar in my DC disconnect box to a dedicated 8' ground rod. Could have used 6# since my max breaker is 125A.

---Module---
10# running from Panel to 15A breaker in disconnect.
12# insulated wire equipment ground running from panel to ground bus in disconnect.(This is temporary, HD only has 6# bare copper which I thought overkill, 12# should in theory be good?) NEC I think says requires conduit or something...
Right now this module is on the ground.

---Charge Controller---
#10 negative from Module and #10 positive from 15A breaker in disconnect box

8# positive runs to 30A breaker in disconnect which then runs to positive on battery. I called Morningstar and they said 30A breaker is ok to use instead of 25A fuse. .
8# negative runs to negative on battery(negative lug in disconnect box)


---Battery---
18 inch #4 Automotive battery cable (temporary till I get my lugging tool) Postive terminal to 125A breaker in disconnect box.
18 inch #4 Automotive battery cable Neg. terminal to negative lug in disconnect box.
!?!?!I should probably run 2# in free air since my breaker is 125A? I have a 63A breaker which I thought should be adequate and minimize my need for large gauge wire, then use 6 or 4#?

---Inverter---
--DC IN--
6# 18inches negative lug in disconnect to negative in inverter DC in.
6# 18 inches positive from 125A breaker to inverter DC in.
Morningstar also said this is ok, 125A breaker instead of 100A fuse.
4# ground running from inverter to ground bus in disconnect.

!?!?!?This should also be the same as that from the battery.

--AC Out--

????
Right now I just have an unprotected/ungrounded outlet for temporary measure with a CFL plugged in. My plan is to get a simple breaker box to run the 2 AC leads from the invert to. From the AC breaker I will run a ground wire back to my DC Ground Bus? Also, will have a DC breaker, manual specifies 3amps Didn't call morningstar to check if I could use larger. 3A hard to find? I don't think NAWS sells them?

Another question is this grounding electrode is 4# and I have heard/read that grounding electrode should be the largest in the system?!?!? That would be costly, and don't think I have ever seen that done.


I uploaded a picture of my current setup....still trying to get color coding straight.
My grounding conductor I need to add 3 white stripes? positive should be red or have red strip? Also, don't have my lightning arrestor hooked up yet...which brings up one last question, can I just stick the + and - leads from the arrestor just in with the panel leads to the charge controller? Seems a little hokey, probably splicing it in would be best?




Thanks a lot!!!

Comments

  • GreenPowerManiacGreenPowerManiac Solar Expert Posts: 453 ✭✭✭
    Re: Hows this system sound? wires and breakers.

    2- 6volt batteries in series could be anywhere between 50-100Ah

    125A main breaker is overkill on a 205W panel.

    This setup sounds like something for a 2-5kw system. I guess it'll never overload the wires.

    The grounding wire size is not much of an issue unless there is a lot of lightning in your area. #10 bare wire to a grounding rod would suffice.
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  • dwhdwh Solar Expert Posts: 1,341 ✭✭✭
    Re: Hows this system sound? wires and breakers.
    micahv wrote: »
    My grounding conductor I need to add 3 white stripes? positive should be red or have red strip?

    The three white stripes are for AC NEUTRAL...IF the wire is bigger than #6 (i.e., #4 and up).

    AC rule of thumb:

    Ground is bare or green.
    Neutral is white or gray.
    Any other colors are Hot.


    DC rule of thumb:

    Ground is bare or green.
    Negative is black.
    Any other colors are Positive.
  • KamalaKamala Solar Expert Posts: 452 ✭✭
    Re: Hows this system sound? wires and breakers.

    I think the batteries are 6V @ 200AH. Just like mine. Still don't know for what purpose the system is intended. A search for all threads started by the OPr tell me that it is "experimental with plans to go GT."
  • micahvmicahv Registered Users Posts: 17
    Re: Hows this system sound? wires and breakers.

    I got the batteries at Costco for $80, I think they are the same as the Walmart ones. Anyhow my intent of the system for now is to have a few outlets/lights in my house powered solely by this sytem. Total load is around 250-300W is everything is on as it exists today, and usually not everything will be on. I did a load analysis and it will be a little tight in the winter, but I can always plug stuff into another outlet.

    I got one light fixture that has a 60w incandescent using one of those small socket bulbs...haven't even looked to see if CFL is available. There is nothing critical on this circuit, just might be inconvenient to not have light in the bedroom.

    Also, I just got that Midnight Solar Disconnect cause it seem simple at the time and came with the 125A breaker. In hindsight I probably should have just got 3 DC breakers...but then again as system grows this will be more suitable.

    Thanks again.
    Kamala wrote: »
    I think the batteries are 6V @ 200AH. Just like mine. Still don't know for what purpose the system is intended. A search for all threads started by the OPr tell me that it is "experimental with plans to go GT."
  • icarusicarus Solar Expert Posts: 5,433 ✭✭✭✭
    Re: Hows this system sound? wires and breakers.

    CFLs come in all base sizes including candelabra base.

    BTW 300 watts is a pretty big load for such a small system. My quick rule of thumb is to take the name plate rating of the Pv, divide by 2, and then multiply that number by the average number of hours of GOOD sun. (usually ~4)

    So in your case, 205watts/2=102.5 watts X4=410 watt/hours/day. This takes into account all cumulative system efficiencies, Pv/wiring/charge controller/inverter/battery charging eff etc. That 410 would be enough to run your 6 watt bulb for ~6.8 hours. Or 250-300 watt load for less than two hours.

    Tony
  • micahvmicahv Registered Users Posts: 17
    Re: Hows this system sound? wires and breakers.

    250-300W is total, if everything is running all at once. Here is a load analysis I did, also kind of worse case...LR/DR light usually not on except when having a party.

    Item Qty W Hr/ W/Hr/
    day Day
    1 Stereo 1 100 2.5 250
    2 Floor Light 1 13 8 104
    3 LR Ceiling Fan 1 50 2 100
    4 Pourch Light 1 13 8 104
    5 Kitchen Light 2 23 4 184
    6 DR Light 1 26 8 208


    Which gives me about 950 W/Day

    Looking at PV Watts my lowest solar radiation is 4.1(6.39 highest) and AC energy is 19.5KWh/month(0.629/KWh/day) which is low for the above, but usually just kitchen and pourch on most days. Nothing here is critical, get rid of stereo on this circuit would probably free it up a lot...also fan not usually running in winter, so that would be down to 850W/Day...again I"m doing this to get some hands on experience, and would agree this is not a deliverable system since I do expect the lights to dim on occasion :)

    I have another circuit that is running lights, laptop and TV...I need to get my kill-a-watt meter back from my friend to figure out what that TV runs, and this other laptop I got running now I was assuming around 50W power draw. Again nothing is critical on these circuits and I can even just plug stuff into another circuit if I need to.

    If I could detangle the wiring mess in my house I would like to get just two outlets in one room running off my system...which I will probably still try and do in the future, but for now I'm just hoping to get something running.

    Thanks for the feedback!
    icarus wrote: »
    CFLs come in all base sizes including candelabra base.

    BTW 300 watts is a pretty big load for such a small system. My quick rule of thumb is to take the name plate rating of the Pv, divide by 2, and then multiply that number by the average number of hours of GOOD sun. (usually ~4)

    So in your case, 205watts/2=102.5 watts X4=410 watt/hours/day. This takes into account all cumulative system efficiencies, Pv/wiring/charge controller/inverter/battery charging eff etc. That 410 would be enough to run your 6 watt bulb for ~6.8 hours. Or 250-300 watt load for less than two hours.

    Tony
  • BB.BB. Super Moderators, Administrators Posts: 32,026 admin
    Re: Hows this system sound? wires and breakers.

    Roughly, an Off Grid system with battery and inverter is 50% efficient (based on solar panel STC / Marketing ratings).

    850 Watts*Hours per day / (4.1 hours of sun * 0.50) = 220 watts minimum of solar panels

    Grid Tied systems run around 77% efficient (batteries and extra inverters waste quite a bit of power).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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