Finally hooked up the system, WOW

bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
Well, it's 8:30 am here, first day with our 800 watts of solar working, and the 10 cubic foot 110v refer, 12 cubic foot 110v freezer, and my desktop computer/satellite modem are all on, AND I'm making 204 watts into the batteries.

All I can say is WOW!
Other than that, I'm about speechless.

DH did a great job getting everything hooked up, everything seems to be working just as it should, and I LOVE the Trimetric!

Oh, and now there is 210 watts going into the batteries....
Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.

Comments

  • solarixsolarix Solar Expert Posts: 713 ✭✭
    Re: Finally hooked up the system, WOW

    Al right! Isn't that first reaction to harvesting your own power wonderful? I have considered hiring one of those party catering companies to show up at the turn-on event just to reinforce the happiness our customers feel.
  • BB.BB. Super Moderators, Administrators Posts: 30,052 admin
    Re: Finally hooked up the system, WOW

    Is "DH" "dear husband"?

    By the way, remember that the batteries do need their charging current--so during the day, you should be pumping as much energy into them as possible for you to draw out later at night.

    If you are barely charging during the day, you will not have the reserve power for night-time loads.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
    Re: Finally hooked up the system, WOW

    Solarix, you are right! It DOES feel like party time!

    BB, yes, DH is "internetspeak" for Dear Husband.

    I understand about the charging, both the freezer and refer are on timers so they will alternate running, and I'm about to turn off the computer and go garden for a bit.
    But I need to see what happens amps-wise when I do so, because the FM60 can put out 60 amps, and our batteries should only bulk charge at 40 amps or so, I don't want to charge them at too high a rate. So I may need to leave the computer and a light or two on to keep the amps around 40 into the battery.

    All will be well when we add two more batteries hopefully next month...
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • BB.BB. Super Moderators, Administrators Posts: 30,052 admin
    Re: Finally hooked up the system, WOW
    bbbuddy wrote: »
    But I need to see what happens amps-wise when I do so, because the FM60 can put out 60 amps, and our batteries should only bulk charge at 40 amps or so, I don't want to charge them at too high a rate. So I may need to leave the computer and a light or two on to keep the amps around 40 into the battery.

    Typically, for your system, the peak average solar charging current will be around:
    • 8x100 watts * 0.77 derating * 1/14.5 volts = 42 amps or so
    You have thin film panels which will provide extra power (20% or so) during their first few months before falling back to their rated values.

    I would not recommend "wasting" power to keep the battery charging current low(er). Hot summer days, you will get less current. Cold winter days you will get higher current but less hours of sun.

    Goal #1 is to not let the battery become "deficit charging"--I.e., using a bit more energy per day than you are returning back to the battery.

    The Battery and Charge Controller will work out their differences. Once the batteries are nearly full--then you can use "free energy" while the sun shines (typically water pumping, washing cloths, etc. during the afternoons).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
    Re: Finally hooked up the system, WOW

    ok.
    I thought that because the 800 watts of panel are the most the FM60 takes at 12 volts, and that it is rated to put out 60 amps, that what I would get from about 10am to 2pm would be 60 amps....but being this is the first day, I haven't had a chance to see what happens.
    SO, the FM 60 will not put out 60 amps when fully loaded??
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • BB.BB. Super Moderators, Administrators Posts: 30,052 admin
    Re: Finally hooked up the system, WOW

    Will you get more out of your system with new panels on a cool day--Your peak could easily be > 60 amps:
    • 800 watts * 0.95 charger eff * 1/13.0 volts charging battery = 58.4 amps or more
    As the thin film panels age (around 6 months), as you hit higher summer temperatures, as dust collects on the panels, etc... The peak current will slowly fall.

    The big thing to remember is your hardware will work pretty well no matter how you beat it up (within reason)... The batteries, however, will not. If you do not treat them well, you could kill them in weeks or months (or even days) instead of getting the 5-10 years or so you would like from them.

    It will take you few days to see how your system performs and what your loads are like... And you will probably see your system in "float" in the afternoons and that is the time to start adding your optional loads.

    Remember, the charger is outputting all the available current until the battery system hits ~14.5 volts (or whatever your absorb setting is). At that point, the battery is ~80-90% charged and it is starting to reduce its current draw.

    And, at the same time, the charge controller may be throttling back on its current output to keep the set-point voltage.

    At that point, you can start drawing your "free power" for other needs--as otherwise, that current will be lost (battery will accept less current as it approaches 90-100% state of charge).

    If you are getting your batteries above ~90% state of charge at least a few times a week, and avoiding much time below ~75% state of charge (sulphation region), and avoid going below 50% state of charge very often--You should have a nice long battery life.

    Also, if you have flooded cell batteries--watch the water usage... Too much water usage, you may want to crank back on the Absorb time/voltage. Too little water usage, check your loads and voltage set-points/timers.

    What is the "optimum" amount of water usage--Just a guess but if you refill (not overfill) about every 2nd month on average--You should be doing OK.

    And you may want to change the absorb time between winter and summer (winter >4 hours; summer ~2 hours)...

    At least as a starting point. Others with Outback chargers can probably give you better pointers than I.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
    Re: Finally hooked up the system, WOW

    Hi BB,
    I just went out and reset the charging amps set point up to 60 amps, I had it throttled back to 40 amps, and the output immediately went up to just over 55 amps, but inside the house I had the inverter on, the refer or freezer were probably on, and the amps were at 44 according to the Trimetric, with the computer back on, I'm getting 36 amps into the batteries.
    No way do I want to charge the 395 amp hour batteries at 55 amps...

    The batteries are already at 91% full from a low this am of 68%, so I think it's charging fine, will be in absorb soon I think, and it's only 11am..

    The Outback tech suggested setting absorb time for 3 hours so it could change to float based on amps rather than time, so I did that...the amps to change to float is set at 8amps, which is what Trimetric recommends according to their formula.

    Most days we were getting to 100% full just on the gennie, so I'm going to aim to do that as close as possible with the solar...

    We are bulk charging at 14.8v.
    Thus far in several months with these new batteries I have not had to add any water. We have one of those "automatic" water filler cans that you push down on and the water flows into the batteries IF and only if the water level is below the filler spout, and thus far, no water has gone in. That can is great for me because even with a flashlight I have trouble gauging the actual depth of the water, something to do with my glasses I think...

    Four of the panels are dirty, but I don't want to wash them off while they are hot, will wait until after dark to do so. Tomorrow the output should be even greater when they are all clean.


    I'm just thrilled to have it all working, it's like magic. I "knew" it would work, but to actually be doing it is quite a feeling of triumph mixed with relief mixed with disbelief that those 8 glass thingamabobs REALLY are running my house!!!
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • BB.BB. Super Moderators, Administrators Posts: 30,052 admin
    Re: Finally hooked up the system, WOW

    From where you were last August (2010):
    bbbuddy wrote: »
    Background:
    We have been off grid for 6+ years in northern AZ, and have lived with an old Trace 2012, 4 L-16 batteries, and multiple generators which have supplied the power. Oh, we do have 40 WHOLE WATTS lol of solar that came with our 5th wheel.

    The Trace charger function has now messed up badly twice and ruined the battery bank, it holds maybe 1/9th the amps it should.

    So, while exploring options online, I ran across the sunelec.com $1.20 per watt Dupont solar panels, and jumped on it, along with a Flexmax 60 controller for those 76 volt panels.
    We bought 8 panels, and a neighbor bought 2 but later had second thoughts, so we will get his as well, for a total of 1000 watts.

    Naturally we have to get a new battery bank, and now NEED to upgrade to 24 volts to handle the panel output (76 volts @ 13.34 amps in parallel).

    Our 8cf propane fridge let all the ammonia out earlier and rather than fix/replace for $1200+, we got a 10cf 110v fridge from Lowes for only $340 thus helping to pay for the solar panels.

    So, being that we already had a 10cf freezer to store my DH's occasional elk, etc. we now have about 2200 watts total of cooling (freezer AND fridge) to deal with, my 8+ hour per day internet habit, 240 watts of lights at night, and tv at night.
    I figure about 4200 to 5000 watts per day would keep us fat dumb and happy.

    Laundry and once-a-week well pumping could stay on the gennie.

    Naturally at this point I thought all I had to deal with was mounting the panels, and buying the new inverter and load center, although my DH is a commercial construction electrician-turned-superintendent, so I was thinking maybe we could make do without a commercial load center and wire the components up ourselves...

    So my first question here remains what problem(s) with the Flexmax 60???

    Oh, I will have a ton of future questions, too, lol.
    It does have to be almost magic now that you will have most of the year with Zero genny noise. :D

    What you do not want to do is put large amounts of current into your battery bank for long periods of time... Short time is not going to be an issue..

    The 13% rate is the typical (always check the battery manual for your vendor's recommendations) maximum sustained charging rate recommended for a long battery life--Higher rates could overheat the battery bank--Monitor your battery temperature and makes sure that it does not get too hot.

    13% becomes the, roughly, a cost effective maximum array size... People put 25-30% sized battery chargers on banks all the time--mostly these are grid and generator powered devices (high peak power is typically much cheaper than paying for all that solar glass out there).

    Watch the Specific Gravity and understand the Trimetric and what it is telling you.

    No water for flooded cell batteries could indicate undercharging.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
    Re: Finally hooked up the system, WOW

    Wow, you dug up that old post!
    What it tells me is that it took me a LONG time to learn as much as I could, and it took us a LONG time to do it ourselves, but DH works full time, weather gets in the way, and so does doing it bit by bit as the $$ allows.

    One thing I found is that all the small "bits and pieces" needed to hook it all up properly cost at least as much as the panels, inverter, and charger.
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • SlappySlappy Solar Expert Posts: 251 ✭✭✭✭✭✭
    Re: Finally hooked up the system, WOW

    bbbuddy, congrats on throwing the switch, and letting the sun power you items, it is a great feeling, and that smile will be with you for along time. mine has been running for 2 yrs, and still get the "smile" :D

    But you are right, all those bits and pieces do add up quick!
  • petertearaipetertearai Solar Expert Posts: 416 ✭✭✭✭
    Re: Finally hooked up the system, WOW

    Fantastic . Looking at your system i would not worry about over amping the batts.as I don't think they would have a high charging current for too long.
    Assuming you have a temp sensor on your fm60 it will automatically shut down the current at 50 deg c.( yes 50 deg is not good but at least there is some protection there.)
    As for the absorb time, I have set mine to 3 hours but also set an end amps so if the end amps gets reached before 3 hours the fm80 will go into float.
    Yes I enjoy the power from the sun, After my last big upgrade of panels and electric fridge I had to send text messages the friends "News flash sun keeps beer cold"
    2225 wattts pv . Outback 2kw  fxr pure sine inverter . fm80 charge controller . victron battery monitor . 24 volts 450 ah surette batterys . off grid  holiday home 
  • bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
    Re: Finally hooked up the system, WOW
    As for the absorb time, I have set mine to 3 hours but also set an end amps so if the end amps gets reached before 3 hours the fm80 will go into float.

    Yes, that is what I did, end amps are set to 8 amps...
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • BB.BB. Super Moderators, Administrators Posts: 30,052 admin
    Re: Finally hooked up the system, WOW

    One issue with "end amps" is if you have other loads during daylight hours--Your loads will "trick" the end amps detection and keep the controller in absorb longer than you would have planned.

    The absorb timer may be a better solution here. On the other hand, if you have large operating loads during daylight hours--most of the energy is going to the loads instead of charging the battery bank--so it is easy to trick the timer too.

    Monitoring your battery with the battery monitor will tell you how well your battery bank is recharging (and using a hydrometer to measure specific gravity if flooded cell) is important to see if "on average" you are still getting the battery over >90% state of charge a least a couple times a week.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
    Re: Finally hooked up the system, WOW

    We have never charged the batteries to less than 95%, but MOST days we have gone to 100%, and yesterday, our first day on solar, we were in float by 2:30; perhaps earlier, but that was when I checked the FM 60....
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Finally hooked up the system, WOW

    congrats on your system being operational. please don't worry about going to about a 14% rate of charge as going over 13% a bit may only mean more maintenance more often for a fla type battery. it won't be very dramatic and 13% is somewhat arbitrary. don't forget that as was pointed out that outputs may fall off a bit from the pvs in time and when using loads it would also drop the input charging current lower. i am not suggesting leaving loads on to lower it, but the higher current will help insure it will get charged even during some loads. if we were talking 20% or 30% charge rates then there would be cause for concern for fla batteries. if they are heating up then put a bit of space between the batteries to allow natural circulation.
  • bbbuddybbbuddy Solar Expert Posts: 125 ✭✭✭
    Re: Finally hooked up the system, WOW

    Update:
    Our system is working great, we made 5.1 kwh yesterday.

    I quit using the timers for the 110v refer and freezer, they are both on full time now until we go to bed, and still we go into float early, and don't go down to even 70 percent on the batteries at night, except for once when I was "testing" them and went down to 68%

    Yesterday I ran my bread machine and made bread using all the extra watts. I timed it so it would do the cooking after we went into float and had all the extra watts available, batteries stayed at 100%.

    Couldn't be happier! AND couldn't have done it without all the great info I got from reading this forum and searching the old posts!

    THANKS TO ALL OF YOU!
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
Sign In or Register to comment.