off grid, new/bigger system

bbbuddy
bbbuddy Solar Expert Posts: 135 ✭✭✭
BB. wrote: »
A 120 watts of solar panels is a quite small installation...

For the normal 60-80 amp solar charge controllers, the minimum panel recommendation is probably ~400 Watts. Any less than that, and the controller consumes a fair amount of power just operating.

Maybe a ProStar 15 solar charge controller, 48 Volt would be an OK replacement (read manual for details) for the BZ.

Otherwise, the Xantrex and Outback line of charge 60-80 amp charge controllers is the place to start looking (you should ask Outback if they have fixed their firmware(?) issues with the Flexmate series yet).

-Bill


Hi all, new to posting here.
This post is what had me sit right up and start posting here, as I have been reading on and off for a bit, but never saw this issue before.

What "firmware" problem is Bill referring to?

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.
Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: off grid, new/bigger system

    If you are not having problems--I don't think you will... There was a period (from what I recall) where the FM charge controllers were "turning on" at night. There were some work-a-rounds but I guess a firmware fix (or other) would have been required...

    That was quite a while ago--and I have not read anything about it since.

    I am not in the solar biz or connected with Outback in any way--so I don't have any more information at all.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: off grid, new/bigger system

    Think that Bill has the FM problem correct.

    Here is a link to the OB forum, there was quite a lot of traffic there, and some here, I think. This topic has become quiet, so believe that the issue has been resolved :

    http://www.outbackpower.com/forum/viewtopic.php?f=29&t=3142

    There are many FM in the field, and if there was still a problem with them, you would hear about it.

    Good luck with the renewed system, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: off grid, new/bigger system

    From your load list, (fridge and freezer), unless they are very special, they will need nearly every bit of your 2000W of PV. If you have not bought the new inverter yet, consider a 48V system instead of 24v. I suspect you will need to run even more PV, or your generator to keep ahead of the fridge and freezer. I just installed a new energy star fridge/freezer, and logging seems to show it uses about .85KWh a day.
    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 ,

  • bbbuddy
    bbbuddy Solar Expert Posts: 135 ✭✭✭
    Re: off grid, new/bigger system
    mike90045 wrote: »
    From your load list, (fridge and freezer), unless they are very special, they will need nearly every bit of your 2000W of PV. If you have not bought the new inverter yet, consider a 48V system instead of 24v. I suspect you will need to run even more PV, or your generator to keep ahead of the fridge and freezer. I just installed a new energy star fridge/freezer, and logging seems to show it uses about .85KWh a day.

    Thanks for the replies guys, whew! GLad I didn't mke a mistake getting that FM60!

    mike90045 yes, the fridge and freezer WILL be the energy guzzlers. They each use about 1050 watts per day, for a total of 2100. However with solar at $1.20 per watt it didn't make sense to spend that $ on super expensive appliances.

    I would rather add panels as I need them.
    Plus I am in AZ, so get good solar exposure, and we have 40 acres to put panel on, lol!

    The $ in new propane fridge will not be as good a return as putting that into panels.

    We do not have a new inverter yet, but my loads are fairly low, and I have read that staying in the 50-70 percent range for the inverter will yield greatest efficiency, thus I was thinking along the lines of a1524 or 2024 size wise.
    If the lights, computer, tv, freezer, and fridge were all on at once, watts would be about 660 not counting surges.. I don't run anything else; well hardly ever. Phone chargers, etc every few days...

    Why go to a 48 volt system? What would be the logical reason there?
    Thanks!
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • petertearai
    petertearai Solar Expert Posts: 471 ✭✭✭✭
    Re: off grid, new/bigger system

    Interested in make of energy efficient fridge freezer.Im looking at a samsung 239l 2.5 star around 338 kw per year . $560.00 nz cheep compared to gram or vest.
    2225 wattts pv . Outback 2kw  fxr pure sine inverter . fm80 charge controller . Mate 3. victron battery monitor . 24 volts  in 2 volt Shoto lead carbon extreme batterys. off grid  holiday home 
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: off grid, new/bigger system
    bbbuddy wrote: »
    Thanks for the replies guys, whew! GLad I didn't mke a mistake getting that FM60!

    bbbuddy,

    I am certain that the issue with the Outback FM series of Charge Controllers is resolved. The issue dates back to 2008. There have been no reports that I've seen stating that the new Firmware did not resolve the problem.

    You might find that the FM-60 or FM-80 are better for your application than the alternatives. Personally, I would have NO concern in buying an FM CC at this point, with the latest firmware. Outback could not afford to allow this problem to continue without resolution. In my applications, the FM is the best suited of the current crop of CCs. I am trying to wait for the Midnite Classic CC, which may start shipping next month ... whatta I know (?).

    My 5.75 year Outback MX-60s (the predecessor to the FM CCs) have worked quite well, and, OB is legendary in their customer support.

    I have no relationship with OB, other than being a very satisfied customer. Some here may seem a bit biased to other companies, but, a few have had business ties to those other companies, is seems ... YMMV Good Luck, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • trkarl
    trkarl Solar Expert Posts: 33
    Re: off grid, new/bigger system

    I second what Vic said about the Outback cc. My MX60 and FM80 work fine. I had to go through several firmware upgrades on the FM80. I don't have the latest FM firmware but it still works fine. Anything 2.**** in the firmware seems to have solved the problems.
  • bbbuddy
    bbbuddy Solar Expert Posts: 135 ✭✭✭
    Re: off grid, new/bigger system

    OK, well all of you have relieved my mind I always thought the Outbacks had a great reputation, so that is why I was wondering about Bill's post. Now I am very relieved.

    petertearai, I don't understand your post, can you clarify??
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: off grid, new/bigger system
    Why go to a 48 volt system? What would be the logical reason there?

    Less overall losses ( half the amps, easier starting loads )

    ability to have 1 string of batteries (parallel batteries are tricky, more strings in parallel, more ways to go wrong)

    2x the size of solar array feeding the same charge controller
    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 ,

  • petertearai
    petertearai Solar Expert Posts: 471 ✭✭✭✭
    Re: off grid, new/bigger system

    Hi petertearai here.It was a question of mike in your thred as he mentioned installing some new refrigration.
    I instaled a fm 80 a year ago software ending in .8 or 8 ( cant remember) and all well with it. 500 watts of pannel. Off grid weekend use.
    Regards Peter
    2225 wattts pv . Outback 2kw  fxr pure sine inverter . fm80 charge controller . Mate 3. victron battery monitor . 24 volts  in 2 volt Shoto lead carbon extreme batterys. off grid  holiday home 
  • bbbuddy
    bbbuddy Solar Expert Posts: 135 ✭✭✭
    Re: off grid, new/bigger system
    mike90045 wrote: »
    Less overall losses ( half the amps, easier starting loads )

    ability to have 1 string of batteries (parallel batteries are tricky, more strings in parallel, more ways to go wrong)

    2x the size of solar array feeding the same charge controller

    Mike90045, are you saying an inverter like an Outback 4048 would start loads easier than an Outback 4024?
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: off grid, new/bigger system

    The BATTERIES have an easier time. A 24V system needs 300A to start a motor load. The same load on a 48V system, would need 150A (from a 48V bank) If you had 2 banks of parallel batteries to make a 24V system (4, 12V batteries), just taking and re-arranging them into a 48V bank (4, 12V in series), the batteries are able to supply the lower amps much more easily, and you loose less voltage in the interconnect cables. Same system wattage.
    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 ,

  • bbbuddy
    bbbuddy Solar Expert Posts: 135 ✭✭✭
    Re: off grid, new/bigger system

    ok, so the lowest amps possible is what to shoot for?

    What about the inefficiencies in running a 4000 watt inverter when "most" of the time the loads will be maybe 3-400 watts?
    Magnum4024PAE, 2 Midnite Classic 150s, 3100watts solar, 432ah lifepo4 battery.  Off grid since 2004.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: off grid, new/bigger system

    You may be better off running two inverters--a small one for your smaller loads, and a large one for the well pump/shop tools/large appliances that only runs when they need the power.

    Standby and tare losses are real and can eat into a system's energy budget pretty heavily.

    You have to look at the standby and low power losses and see what works best for you.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: off grid, new/bigger system
    bbbuddy wrote: »
    ok, so the lowest amps possible is what to shoot for?

    What about the inefficiencies in running a 4000 watt inverter when "most" of the time the loads will be maybe 3-400 watts?

    The only losses to worry about are the standby and no-load power of bigger inverters - unless you're really drawing very little from them. The inverters themselves are more efficient when running at lower power draw. Attached is the efficiency curve of the 5kW Sunny Island inverter where you can see it's most efficient between 500W - 1500W of load. Although efficiency is very bad (less than 90%) below about 150W.