New offgrid skoolie setup, need some help !!!

skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
Hey guys !!! Im just finishing up a skoolie/offgrid bus conversion build.. i just finished installing the battery bank/inverter/controller... ive done a massive amount of research to get to where im at, not just on solar but building a shower, bathroom, kitchen, plumbing, hardwood floors, lighting ect ect MY BRAIN IS OVERLOADED !! I JUST NEED SOME HELP !!

i have 4 6v gc2 215ah batteries ran in series to make (2) 12v then parallel ... i have a 1500w pure sine inverter and (4) 100w renogy 12v panals... the charge controller is a epever 30amp mppt. .....

Everything is wired with 3/0 wire and properly fused ....IM JUST ABOUT TO INSTALL THE PANALS and was going to run them in parallel ??? i turned on the controller today and it says 24v 30amp ??? Im assuming that it means (2) 12v banks =24v ? Im lost as to how i should wire the panals ??? Im also kinda lost as to what i really have here and what float/charge im aiming for with my setup ? Normally i would never ask for help, i would just read more but im burnt out right now !!! THANKS GUYS

Comments

  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
  • PhotowhitPhotowhit Solar Expert Posts: 5,011 ✭✭✭✭
    4 in parallel would normally call for fuses or breakers and MPPT works best with incoming voltage about 2x the charging voltage, so I'd suggest running them, like your batteries 2 in series and 2 strings in parallel. With just 2 strings they can be run with out fuses or breakers, and you could just use branch connectors.

    Not sure why your charge controller says 24 volt. You might check to see what voltage the charge controller is 'seeing'. Normally inexpensive charge controller  require hooking up the battery bank first and 'sense' the correct voltage. Though perhaps there is a jumper to set. Sorry, I think this is your manual...lol

    http://www.epsolarpv.com/en/uploads/news/201512/1449040581526220.pdf
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    I have (2) sets of 4 to 1 branch connectors 4 female to 1 male ... 4 male to 1 female. ... i also have 6 Trojan t105s and a "kid" controller, im just trying to learn on this setup so i wont mind if i ruin the batteries as much.... what are my target values i should program into the controller for charging these batteries im using now ? And what would the numbers be if i ran my panals as your saying ? Im trying to figure that out as we speak but maybe you can help... thank you
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    edited April 2017 #6
    I have the mc4 in wire already fused for 30amp ?? But thats still goog because amps stay the same ? You can kinda see it here, old pic but
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    ..... also, i can run the panals in series because the mppt controller takes care of the mismatched volts to battery setup ?
  • EstragonEstragon Registered Users Posts: 4,101 ✭✭✭✭✭
    With an mppt controller you can wire in series. Running higher voltage does make the controller a bit less efficient, and there will be a voltage limit in the controller specs. 2 strings of 2 panels in series is probably a reasonable balance.

    You should hook the controller up to the batteries first, and to the panels second.

    30a fuse sounds big to me?
    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
  • EstragonEstragon Registered Users Posts: 4,101 ✭✭✭✭✭
    The defaults for flooded in the manual linked to by Photowhit look reasonable. Absorb (boost) is 14.6, but maybe a bit short at two hours. Equalize at 14.8 could be a bit higher?

    The manual appears to be for a positive ground model. Presumably yours is negative ground but otherwise the same.
    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
  • PhotowhitPhotowhit Solar Expert Posts: 5,011 ✭✭✭✭
    If I'm seeing your picture correctly, you have a single 30 amp fuse between the array and the charge controller. Not sure that will do anything at all! It won't protect the panels from back feeding each other, the intent of a combiner box with fuses or breakers.

    I wouldn't worry too much about it, it was a common practice 20 years ago. I don't thin 12 volt panels are likely to burst into flames, unless they are homemade panels.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    > @Photowhit said:
    > If I'm seeing your picture correctly, you have a single 30 amp fuse between the array and the charge controller. Not sure that will do anything at all! It won't protect the panels from back feeding each other, the intent of a combiner box with fuses or breakers.
    > I wouldn't worry too much about it, it was a common practice 20 years ago. I don't thin 12 volt panels are likely to burst into flames, unless they are homemade panels.

    Yeah, my original thinking was to run 4 panals in parallel with a set of 4 to 1 branch connectors and the 30amp breaker was because parallel is multiples of amps ? Thats what i thought at least !! Sounded good !! I dont know, thats why i need help ... im leaning towards the 2 strings series / parallel deal.... how does 13.5 float 14.8 bulk sound ?
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    Thanks everyone for the responses !! i mounted the panals today (controller is a positive ground) so i had to do a switcheroo and cross my fingers that nothing burst into flames !!! I only pluged in one panal and hit the breaker, everything went well so i charged my batteries up and then disconnected it... i guess tomorrow i will do the series /parallel setup... so the new question is [ Q: once i do the setup and have just a positive and negative connection to the controller what breaker will work or can i just leave the 30amp the way it is ??? 13.5 float 14.8 boost ???
  • PhotowhitPhotowhit Solar Expert Posts: 5,011 ✭✭✭✭
    edited April 2017 #13
    With an MPPT type charge controller, 2 in series and 2 strings (of 2) in parallel would work fine and require no fusing. The MPPT type charge controller will use what wattage that is available and convert it to the best voltage and amperage for the battery. If you have 300 watts coming in it will and your batteries are still in bulk charging at say 13.4 volts it will give you about 300 watts ÷ 13.4 volts = 22 amps with a little loss during the conversion.

    13.5 float and 14.8 absorb sound fine, don't know what boost is, if it's what we would normally call equalizing, I would want that higher. I'm not familiar with that term.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, 660 ah 24v ForkLift battery. Off grid for @16 of last 17 years. Assorted other systems, and to many panels in the closet to not do more...lol
  • EstragonEstragon Registered Users Posts: 4,101 ✭✭✭✭✭
    Boost appears to be absorb, with voltage held constant for a period of time. IIRC there was a separate EQ setting.
    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
  • mcgivormcgivor Solar Expert Posts: 3,119 ✭✭✭✭✭
    My belief is that  boost  is a slightly  higher voltage charge, not an equalization per say, just a slightly elevated voltage to bring the batteries into alignment for AGM , some AGM manufacturers recommendations allow for this, and some controllers have a setting to provide such a charge. If the batteries are flooded, which they appear to be, a higher setting  would be appropriate for equalization.  
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • westbranchwestbranch Solar Expert Posts: 5,153 ✭✭✭✭
    The most commonly used for that elevated charge id called  '' a Freshening or Re-Freshening charge'  Some AGM manufacturers call for an EQ charge at a slightly higher V than the Freshening charge but NOT at the levels of an EQ for FLA's... and  that is only recommended after some rather exhaustive Capacity testing....
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    Yeah, boost on my controller seems to be " absorb" the controller seems to be on boost most of the day today.... im confused as to what my batteries are supposed to charge to ? The controller went to 13.2 and just kinda stayed there all day, i probably have some limit set that im not aware of... the battery icon on the controller never made it to "full" , it was always 1 bar away from full (5 bars )... its definitely going to be learning curve, i just hope to start off with proper settings so i dont damage anything. .. as of now i cant leave it unattended, i dont trust that its setup correctly.
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    Does this look like a good start ?? Is there something i should change to be safe until i know what im doing ? Is there anything on the controller that i should never do to my specific batteries ? THANKS GUYS !!!
  • EstragonEstragon Registered Users Posts: 4,101 ✭✭✭✭✭
    The batteries should be getting to 14.6 according to the chart if the CC is set to "flooded" which I think yours are. I would increase boost time to 180 mins for now to make sure you get fully charged. You might be able to put it back down if you find the batteries are getting full before the 3hrs is up.

    The high voltage disconnect might be too high for some loads (eg inverter) at 16v.

    I prefer to do equalizing manually when needed rather than by some arbitrary schedule and would turn off auto-eq. I would also increase eq voltage to around 15.5v, but I monitor battery specific gravity, water level, and temp when doing manual eq.

    The biggest killer of batteries is probably chronic undercharging, so the main things to be sure of while you get used to the new system are to not draw the bank down below about 50%, don't let it sit under 80% for more than a day or two, and recharge to full regularly (like at least 1-2x/wk). A hydrometer is an inexpensive and useful tool to monitor flooded batteries, and I recommend getting and using one.
    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
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    > @Estragon said:
    > The batteries should be getting to 14.6 according to the chart if the CC is set to "flooded" which I think yours are. I would increase boost time to 180 mins for now to make sure you get fully charged. You might be able to put it back down if you find the batteries are getting full before the 3hrs is up.
    >
    > The high voltage disconnect might be too high for some loads (eg inverter) at 16v.
    >
    > I prefer to do equalizing manually when needed rather than by some arbitrary schedule and would turn off auto-eq. I would also increase eq voltage to around 15.5v, but I monitor battery specific gravity, water level, and temp when doing manual eq.
    >
    > The biggest killer of batteries is probably chronic undercharging, so the main things to be sure of while you get used to the new system are to not draw the bank down below about 50%, don't let it sit under 80% for more than a day or two, and recharge to full regularly (like at least 1-2x/wk). A hydrometer is an inexpensive and useful tool to monitor flooded batteries, and I recommend getting and using one.

    This is exactly what im looking for, someone to explain how things work !! Im smart and do a ton of research but feel like im just guessing when it comes to this stuff... you said the "high voltage disconnect " might be too high for an item like the inverter ?? How does that work, what is it, how do the 2 relate to each other ? I have the controller set on "user"so i can change things, the chart i posted are the default settings for "flooded" ... i just need someone to help me go down the list and tell me proper settings for each one... i turned off "eq" and will do that when i feel more confident. .. thank you for the response, im going to make a list of the settings and see what im missing. I appreciate the help, right now all my stuff is turned off until i can get my head around this...
  • EstragonEstragon Registered Users Posts: 4,101 ✭✭✭✭✭
    I think high voltage disconnect works as the name implies... the controller will stop trying to charge at above Xv.

    I don't recall if this controller does
    temperature compensation, it probably does. When batteries are cold it takes a higher voltage to charge because the chemical reaction slows down in the cold. Without a limit, the temp. compensated voltage can get high enough to cause other connected equipment to shut down or possibly even be damaged.

    If that's what the limit is for, it may be a bit high. You would want to check the manual for your inverter and anything else connected to the batteries to see what their voltage limits are. You might also want to check the controller manual to make sure this setting is what I think it is.
    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
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    > @Estragon said:
    > I think high voltage disconnect works as the name implies... the controller will stop trying to charge at above Xv.
    >
    > I don't recall if this controller does
    > temperature compensation, it probably does. When batteries are cold it takes a higher voltage to charge because the chemical reaction slows down in the cold. Without a limit, the temp. compensated voltage can get high enough to cause other connected equipment to shut down or possibly even be damaged.
    >
    > If that's what the limit is for, it may be a bit high. You would want to check the manual for your inverter and anything else connected to the batteries to see what their voltage limits are. You might also want to check the controller manual to make sure this setting is what I think it is.

    Ok, got it.... today i turned the setting to "flooded" and the battery icon seemed to charge properly a d the icon finally hit "full bars" but then my voltage started dropping back down to 13.2 then back up to 13.5 and back down 13.2 ???? This is with NO LOAD at all, not off the controller or the batteries. ... is thats normal ? My controller is always in boost charge, i have never seen it say float yet ???
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    The controller does have temperature compensation, i have the temp wire on the side of the batteries and the controller is set to 3mv/30○c...... i think the reason my bars arent going to full is because im putting 430ah for battery capacity. .. im going to try 215ah today , just to see if that bumps up the bars... im hoping that is why the charger never thinks they are full....
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    The controller does have temperature compensation, i have the temp wire on the side of the batteries and the controller is set to 3mv/30○c...... i think the reason my bars arent going to full is because im putting 430ah for battery capacity. .. im going to try 215ah today , just to see if that bumps up the bars... im hoping that is why the charger never thinks they are full....
  • skoolieoffgridskoolieoffgrid Registered Users Posts: 15 ✭✭
    Yep, that was the issue !!! Changed the battery ah setting and now its full on the controller and went to float !!!
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