Help me set-up my system correctly please.

AndyIvyAndyIvy Posts: 12Registered Users ✭✭
Hi All, 
I posted a while ago about building a house off the grid and am at the stage where I have my solar system built and in place. 
I would like some help and advice on making sure I have it set-up correctly to hopefully ensure a long life and efficient charging. 

-What settings should I be looking for and set up on my Charge controller? times, voltages at each stage etc  specifically 
-What settings need to be in the rest of the system for making sure I'm not hurting anything?
-What is my best practice for battery care, upkeep, tips, and tricks? 
-General advice pertaining to my particular set-up, that I may overlook. 

  
Here is my set-up. 
Im in Colorado at about 9000ft and have a great southern aspect for the panels 

ME-ARC Remote 

ME-AGS-N Auto Gen Start (not yet hooked up)

ME-BMK Battery Monitor Kit

MS4448PAE Inverter/Charger 

MAGMMP175-30D Breaker 

MNDC125 or 200 DC Disconnect

ME PT-100 Controller

12x 305W Selivo Solar panels. 3.36kw ( 2 top of pole arrays 6 panels on each)

There are 3 strings of 2 panels on each pole

" the voltage Vmp will be 115V, and the current Imp will be 15.96A. worked out by Horsefly here on the forum"  

Battery's Rolls Surrett S550 I have 16 in total they are 6V [email protected]

they are set-up as 2 strings of 8 in series to make 48v and the 2 strings in parallel so 48V [email protected] 20Hr 

Can I give any more info to help you help me?

Thanks 


Comments

  • Dave AngeliniDave Angelini Posts: 3,762Solar Expert ✭✭✭✭
    edited December 2017 #2
    Why did you pick 3 strings of 2 on a 200V CC please? Too close on max input V probably.
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • AndyIvyAndyIvy Posts: 12Registered Users ✭✭
    Dave, I originally wanted to do 4 strings of 3 panels, but that's more then the CC could handle. 
    So reconfigured to 6 strings of 2 panels 

    This is what we worked out from the Panels Specs 

    "If you do 3 strings of 2 panels on each pole, the voltage Vmp will be 115V, and the current Imp will be 15.96A. You can use any wire that has a resistance of 1.351 ohms/kft or lower. According to NEC ch 9 table 8, you'll need #10 wire or larger.

    If you do 2 strings of 3 panels on each pole, the voltage Vmp will be 172.5V, and the current Imp will be 10.64A. You can use any wire that has a resistance of 3.04 ohms/kft or lower. From the same table, you would be fine with #12 wire or larger."

    In real life the 2 strings of 3 panels produced 205V and my controller showed a "High PV input Fault" , if run in that configuration. 
    Reading through the manual this PT-100 CC will not work beyond >187 VDC. So that's why I reconfigured the pannes to be 6 strings of 2 panels. They are producing about 133V which is also higher then we calculated as well. 
  • EstragonEstragon Posts: 2,436Registered Users ✭✭✭✭
    I would start with the voltages recommended by Rolls for absorb and float, and do any recommended commissioning charge. Start a logbook for regular checks of specific gravity, equalizations, and charging regime changes.

    It sometimes takes a month or two of regular cycling to get things dialled in for your specific system and usage patterns. I would also avoid "babying" a new bank. Once you've established you have adequate charging capacity, taking them down to ~50-60% state of charge and promptly (next day) hitting them with good bulk charge regularly supposedly helps better break them in.

    I would check SG often (maybe weekly) at first. That's the best way to establish what, if any, tweaking of charge settings etc might be needed.

    If my arithmetic is right, 3300w of pv gives you ~55a charging, which is a bit low for 850ah bank. If you find it isn't keeping up with loads (especially at this time of year), I would run the generator for a couple of hours in the morning to make sure the bank is fully charged at least a couple times a week.
    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
  • HorseflyHorsefly Posts: 306Registered Users ✭✭✭
    Sorry @AndyIvy - I must have made a mistake when I said that 2 strings of 3 would be OK.  I'll go back and re-look at that.  If you ended up with 3 strings of 2 per pole, it meant you had potentially higher current, so you needed bigger wire. Did you end up using #10 wire from the pole combiner to the CC?

    I looked at the Rolls Surrette manual. It looks like for your 48V configuration you'll need to set up your CC with the following parameters (others here can double check my work, hopefully):
    1. Bulk / Absorption voltage: 60V
    2. Float voltage: 54V
    3. Equalization voltage: between 62.4V and 63.6V
    These voltages need to be temperature compensated. Your CC should have come with a BTS (Battery Temperature Sensor), which should connect to the CC. The sensor itself should be mounted on the terminal of one of your batteries or on the surface of the case. Rolls says the temperature compensation should be set to 5mV /deg C/cell. In your 48V configuration you have 24 2V cells, so your temp compensation should be 120mV.

    Rolls also recommends end amps be set to 2% of the 20AH rating of the battery. For your 856AH bank, that's about 17A. If your CC has a setting for end amps (or "return amps") you can set it. I know my Schneider CC doesn't have a setting for end amps, but instead just goes for 2%.

    There's also some stuff about the max absorption charge time in the manual, but it is computed based on your normal charge current. 

    Off-grid cabin: 6 x Canadian Solar CSK-280M PV panels, Schneider XW-MPPT60-150 Charge Controller, Schneider CSW4024 Inverter/Charger, Schneider SCP, 4 x Vmax XTR12-155 12V, 155AH batteries in a 2x2 24V 310AH bank.
  • EstragonEstragon Posts: 2,436Registered Users ✭✭✭✭
    Those voltages look on the high side of right. IIRC, Rolls does suggest pretty high voltages vs others. You might want to see if temp compensated EQ voltage could be an issue as a really cold bank might get voltage too high for the inverter.
    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 Posts: 1,881Solar Expert ✭✭✭✭
    @AndyIvy Whilst it is useful to have the information details to charge the batteries, it is equally important to include daily loads which have a direct correlation, the amount of PV would be dependent on these figures, including useage wether full or part time use. As noted the array is a little on the small side, unless it is a weekend only use.
      1500W, 6× Schutten 250W Poly panels , Schneider 150 60 CC, Schneider SW 2524 inverter, 8×T105 GC 24V nominal 

  • AndyIvyAndyIvy Posts: 12Registered Users ✭✭
    Guys thank you for taking the time to chime in. 
    "Estragon" 
    Thanks, I will get a log going. This is a new build, I am building the house myself, the system is up and running, however, I'm still months away from having any appliances or real load on the system. So the break-in may be tricky, I would have to maybe disconnect the charging if I need to drop them to 60ish% charge? Any thoughts on that? right now all the inverter is running are some power tools and some led lights within the house. 

    "Horsefly" 
    Your help has been very valuable and much appreciated. 
    The CC and Remote are a little tricky to navigate, not being familiar with them, but I will check Voltages and get them set-up. 
    Yes I have the battery sensor installed. Just a bit of a maze trying to get it all "set-up"

    "mcgivor" 
    Thanks, its going to be a while before I get to see how things are running once I get my appliances in place and hopefully move in. 
    It will be full-time use 2 people.  I oversized the wire back to the house so in the event I need more panels I could add another array.  
    Also burried 2" conduit out to the arrays in case I need to pull something else out there. 
  • Dave AngeliniDave Angelini Posts: 3,762Solar Expert ✭✭✭✭
    No worries about EQ until you move in. At least for now while breaking them in try and get your SG close or just slightly low. Make sure this happens at the time they go to float or adjust the time. Whatever the absorb voltage recommended, set them in the middle for now.
    As said try and cycle them down to 50% with a space heater or large loads. Make sure the strings are very close in SG to each other. Look for outlier SG in the cells. They should be close, but again no worries on getting them to exactly 1.280 or the recommended SG. Your goal is break in the battery bank while making sure that you have good new batteries.

    This is old, simple, and very robust technology so do not worry about it. Enjoy
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • AndyIvyAndyIvy Posts: 12Registered Users ✭✭
    Thanks, Dave, 
    So you guys recommend cycling this bank to about 50% to 60% SOC. 
    Some questions on Breaking them in. 
    -Does this matter if it take's few days to get them down to 50% SOC? or should this be done within one day?
    -How many times should I cycle down to that SOC?  or over what period of time. 
    then thinking ahead, what is a good rule of thumb as to what SOC  I should avoid ever cycling the batteries down to once I'm using the system full time?

    Thanks  

  • EstragonEstragon Posts: 2,436Registered Users ✭✭✭✭
    You would want to get down to 50-60% in a day or two. Avoid having them sit at that level for more than a day or so. Anything under ~75% will allow for a "bulk" charge, during which the batteries accept maximum charging current, which helps "form" the plates to bring the bank up to full capacity. If loads or charging capacity are limited until you move in, it's not a big deal to hold off doing it. I did it once or twice a week for the first 2-3months using the bank. In my case, the system got finished in fall and didn't get used much over the winter, so most of the break-in was the next spring.

    As Dave said, the main thing is to get SGs fairly close between cells, and as close to spec as you can.

    The rule of thumb is 50-60% SOC, but there are really 3 inter-related factors; the SOC, the length of time sitting at low SOC, and the bank temperature. For example, a bank at 50% SOC and 95°f will sulfate much faster than at 35°f.

    I normally fire up the generator at ~60% and charge up to ~80%, unless I'm pretty certain the day will be sunny enough to fully charge with solar alone. At this time of year, the days are too short and sun too low for solar alone in my location. In spring/summer, pv alone would easily charge to full from that level on a sunny day.
    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
  • mike95490mike95490 Posts: 7,703Solar Expert ✭✭✭✭
    Once your PV array is 2 or 3 x battery voltage, higher array voltages cause higher conversion losses in the MPPT controller.  If you have long runs, going to higher PV voltage makes sense.
    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 ,

  • Wbuffetjr1Wbuffetjr1 Posts: 78Registered Users ✭✭
    edited December 2017 #13
    I am always interested to read about high altitude CO systems! I haven't seen anyone mention it yet, but maybe it has already been discussed.  I would imagine your panels will put out more than they are rated for at 9,000'.  I have a 3,100 watt array at 10,000' in CO and highest output I have seen so far was ~4,100 watts. Just hit 3,500 watts yesterday. So POSSIBLY your array isn't as undersized as it may appear on paper? Just a thought from a guy that doesn't know very much! 
  • westbranchwestbranch Posts: 5,041Solar Expert ✭✭✭✭
    edited December 2017 #14
    From what you have told us already the system is telling you  that you need another array to get a proper charge... when you get into more power consuming building activities, you will easily achieve your 65% target.... or more?  ;)
     
    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, Hughes1100 Sat Modem
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • EstragonEstragon Posts: 2,436Registered Users ✭✭✭✭
    At altitude, you get the benefit of thinner air and likely lower temps. In winter, I'm not suprised to hear you're seeing better than STC output. What's it like in summer?
    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
  • Dave AngeliniDave Angelini Posts: 3,762Solar Expert ✭✭✭✭
    edited December 2017 #16
    From what you have told us already the system is telling you  that you need another array to get a proper charge... when you get into more power consuming building activities, you will easily achieve your 65% target.... or more?  ;)
    Seems like the opposite westbranch. He does not live there and has very low loads. He does not need another array at this time for what he is doing. Later, he may also find that if he manages loads he will not need one for some time.

    Pick a good solar day in the early morning, turn on a few 1500 watt heaters and bring the SG down to near 50%. Let the sun fill them up. Do this as much as possible for the next month or two. 

    Very good quality solar panels often exceed STC (by a bunch) at my 3,000 foot elevation in the Sierra so that does not surprise me.

    Steve Higgins from Outback and now Surrette wrote an excellent battery manual that I posted on the forum a few years back. It is the Surrette bible. I gotta go but it is out there. 
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • Wbuffetjr1Wbuffetjr1 Posts: 78Registered Users ✭✭
    edited December 2017 #17
    Estragon said:
    At altitude, you get the benefit of thinner air and likely lower temps. In winter, I'm not suprised to hear you're seeing better than STC output. What's it like in summer?
    Estragon - I can't easily answer that with exact numbers.  I installed my system in late July and left a few days later. I went back thru the logs in late September and saw the 4,100 watts in early September. (I was mainly just looking at high power and float time). I did not get the My Midnite app working until early November so I don't have easy access to the August data at this time. I do know they often exceeded the STC from what I quickly looked at in the log. I will say that thru all the reading I did before I installed my system I never saw a single thing about breaking in the battery bank so I did nothing to break my batteries in.  Not sure how much that affects them in the long run.  Luckily, it's a "cheap" set of GC batteries. 
  • EstragonEstragon Posts: 2,436Registered Users ✭✭✭✭
    The break in will probably happen to some extent in the normal course of cycling the bank anyway. I wouldn't worry about it.

    I love the colour of the sky up high. Always surprised how fast I get sunburned skiing at that altitude.
    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
  • AndyIvyAndyIvy Posts: 12Registered Users ✭✭
    Thanks for the Info guys, much appreciated. 
    I carefully went through the battery bank and checked S Gravit for every cell. (I got 2 Ez-read hydrometers) I check them against each other and they are very close. 
    Right now ALL the cells range from .1250 to .1255 and I took the reading at about 60'F the batteries were in "Float" at the time I checked them. 
    The Controller is not set to specific voltages yet "custom" it is currently just using the Battery monitor kit, and default. 

    That SG reading is a little low for 100%. What do I need to do to get that reading up closer to .1275 ?
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