180watt evergreen/c60 controller

In total ignorance, yet reading a lot, I bought 4 of these panels and the xantrex c60 to charge 8 Trojan T105's, for a home system. Now, I read on the product page that these panels are, "NOT for a 12 or 24 volt battery charging system, unless wired in SERIES, (?) andusing an MPPT charge controller."

Did I blow my money on the C60?

Comments

  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: 180watt evergreen/c60 controller

    A quick response, without reading the specs on either the panels or the controller, but 180wattsx4=720 watts or 60 amps @ 12vdc. There is no room to take into account any increase due to either low battery or colder panels, therefore I think the controller is too small.

    (As I said, I don't know the specs on the controller. Is it 60amps 12vcd and 30 @ 24? or is it 60 amps at either? If it is 60 on either, you could series/parallel you panels to put out 24 vdc (nominal) into the 8 batteries wired in series/parallel for 24vdc.

    Icarus
  • System2
    System2 Posts: 6,290 admin
    Re: 180watt evergreen/c60 controller

    The C60 book says 60 amps continuous, at 12v. setting, and 55vdc maximum PV array open ciruit voltage. I thought that was the cushion for wattage?

    The panels say, 15 amp inline fuse/panel, and output of 25.9 v and 6.95 a at peak power. So, I didn't think I had a wattage problem.

    What bugged me was the statement "wired in SERIES", which confounded me. I wanted 12volts, and it looked to me like all was okay. I expect the charger to waste the excess voltage, above battery needs, or, some part of it. It's a 3 stage charger, with bulk, absorption, and float stages, voltage programmable for those.

    Do I understand correctly that, my C60 will function, but waste more PV power than an MPPT unit, and, not capture and optimize for the peak output and low battery conditions? I don't mind losing some efficiency here, but I don't want to fry anything when I hook it up.
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: 180watt evergreen/c60 controller

    Yeah, those PV modules and that charge controller aren’t particularly compatible for 12 V or 24 V (both nominal) applications. The STC Vmp spec for 12 V battery systems is ~17 V, and for 24 V systems it’s ~34 V. Here are the STC specs for the 180’s:

    Voc: 32.6 V
    Vmp: 25.9 V
    Isc: 7.78 A
    Imp: 6.95 A

    You can wire all four PV modules in series and connect the array to the controller to charge the batteries wired for 12 V (pairs of two batteries in series; four pairs in parallel). The batteries will keep the array voltage from exceeding ~14.8 V whn the controller is in bulk mode, and the controller will keep the battery voltage from exceeding the absorb- and float mode targets.

    See this Trojan battery link for important information on charging and maintaining your batteries: http://www.trojanbattery.com/Tech-Support/BatteryMaintenance.aspx

    The problem with the approach above is that each module’s nominal power rating will drop from 180 W to ~120 W. Typical end-of bulk stage power at mid-day on a clear and sunny day will be ~14.8 V x 6.96 A = ~103 W, or ~412 W for the entire array.

    An MPPT controller will raise the effective array power from ~412 W to ~575 W in the summer, and a bit higher in the winter.

    Sorry about the bad news; I hope this helps.
    Jim / crewzer
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 180watt evergreen/c60 controller

    Those are "18V" panels ...

    You will have no issues with using the C60 but you will only get 14V*7A ~ 100 watt from each panel or about 400watt from the 4 of them in parrallel.

    If this is a concern, then get an mppt controller, blue sky/ bz for low cost or Xantrex XW/Outback MX for high end. These controllers will let the panels run at there rated 25V / 7amp and turn that into 14volt / 12amp or what ever the battery regulation requires.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: 180watt evergreen/c60 controller
    patience wrote: »
    Did I blow my money on the C60?

    possibly. What's the voltage on the panels ? As long as you stay below the kill voltage of the c60 (its a pretty sturdy unit) you should barely be OK. Just Mis-align the panels a little bit, and you now have 150 watt panels. Only when batteries are really low, will they accept full power, and then only for 30 minutes or so, and it starts tapering off.

    In real life, you would get about 75% of panel nameplate wattage. Coupled with the losses in a non-MPPT controller, the C60 should live.

    I know nothing about the evergreens.

    Any chance the dealer will exchange/refund some parts ?
    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 ,

  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: 180watt evergreen/c60 controller

    OOPS!

    I was reading the spec for the C-40 not the c-60.

    I also didn't realize that the evergreen panels were 18vdc nominal either!

    As always there are people here way smarter than I. I would try to trade it off on a mppt type controller, but I would shy away from the BZ. (Read the thread about BZ controllers!)

    Icarus
  • System2
    System2 Posts: 6,290 admin
    Re: 180watt evergreen/c60 controller

    Wow. I'm humbled. And thanks for the help! I'm probably stuck with the C60 for now, but at least I can use it and get something out of it.

    I don't know enough to ask a sensible question, so bear with the newbie, please. I do understand Ohm's Law, but don't know battery characteristics, so , what if I series 2 panels, and parallel 2 groups of two, to get 65.2voc? That exceeds the 55voc rating on the C60, but Crewzer pointed out that the battery bank will limit the voltage? The C60 has a "crowbar" protection circuit, but I don't really want to lean on that. Just searching for optimization of what I have. If you guys say no, so be it, I'll be glad to live with the de-rating, with the panels all in parallel, and keep it safe.
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 180watt evergreen/c60 controller

    Your only option with the C60 is to have the 4 panels in parrallel and charge your batterys all in parrallel ( 12V battery bank )
  • System2
    System2 Posts: 6,290 admin
    Re: 180watt evergreen/c60 controller

    Thanks a bunch! I'll do that. I really appreciate your help. It's been a challenge trying to get info for me.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 180watt evergreen/c60 controller
    Those are "18V" panels ...

    You will have no issues with using the C60 but you will only get 14V*7A ~ 100 watt from each panel or about 400watt from the 4 of them in parrallel.

    If this is a concern, then get an mppt controller, blue sky/ bz for low cost or Xantrex XW/Outback MX for high end. These controllers will let the panels run at there rated 25V / 7amp and turn that into 14volt / 12amp or what ever the battery regulation requires.

    i have add here that the bluesky stuff will downconvert linearly ie, 24 to 12, 26 to 13, 22 to 11, etc. so if the pv is low for 24v it will downconvert low for 12v. also note that bluesky isn't all that cheap anymore. if you go mppt go with the types like the xw60 or mx60 or even that apollo model.
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 180watt evergreen/c60 controller

    I haven't a Bluesky on hand, but my understanding is they are generic buck converters and not 2 to 1 fixed ratio. Also to be an mppt controller they would HAVE to be adjustable, I'm told they are analog with a percentage of VOC to get the mppt point. The spec sheet might be read as they are 24V to 12V, but I had assumed that was to give a generic view of what the controller was designed for.

    If I get one to play with I'll update this to be more specific
  • hillbilly
    hillbilly Solar Expert Posts: 334 ✭✭
    Re: 180watt evergreen/c60 controller

    In reading this I couldn't help but wonder about the extra "cost" of using the C60 charger, vs. plunking down some extra $ on an MPPT charger. Using the roughest of math (my specialty) it seems to me that you could esentially buy a few hundred extra PV watts for less than $2 a watt by purchasing an upgraded charge controller. Your 4 modules at 14.8v * 6.95amps = about 412 watts: a loss of over 300 watts (STC rated watts, not accounting for real world efficiencies, battery charging losses, etc...). NAWS has the MX 60 and the newer Xantrex both for around $500 right now... 300watt panel for $500 seems to be pretty good deal to me, instead of having all that expensive PV just wasted...
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: 180watt evergreen/c60 controller

    Not only that, but, you can off the xantrex on ebay for somewhere close what you pay for it.

    Icarus
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 180watt evergreen/c60 controller
    I haven't a Bluesky on hand, but my understanding is they are generic buck converters and not 2 to 1 fixed ratio. Also to be an mppt controller they would HAVE to be adjustable, I'm told they are analog with a percentage of VOC to get the mppt point. The spec sheet might be read as they are 24V to 12V, but I had assumed that was to give a generic view of what the controller was designed for.

    If I get one to play with I'll update this to be more specific

    very good henry as this is how i interpretted from them. if it is different than i believe it to be, please do say as i have an sb50. i am not running odd voltages from my pvs or downconverting, but it would be good to know i can.
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 180watt evergreen/c60 controller

    Neil,

    I checked out a SB3024i, its a PIC controlled buck switcher and not fixed like you might have thought. I ran a 36V array into a 12V battery and it works as you would expect an mppt controller to work. They also have changed the mppt from what I have been told it was, it appears to be lots of mini-sweeps, like every 10 seconds, not a percentage of VOC, then again this is a somewhat newer model so your SB50 might be different.

    Solidly built, comformal coated, totally different league than the BZ. Efficiency was a bit low ( 92% ) but its got a good sized heatsink so no real issue

    Also tried again BZ, this time NIB. Plain and simple don't ever consider one of these .. tincan packaging, mppt is horrible, no heatsink and obvious design flaws that will cause short life. At best, its a 15-20 amp box, on a good day.

    SG
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: 180watt evergreen/c60 controller

    Question for Solar Guppy answered... delete rest of post.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: 180watt evergreen/c60 controller

    Ladadee ladadaa ... to much sun today :roll:
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: 180watt evergreen/c60 controller

    that still puts doubt on my sb50. if you find out let me know or sometime in the future i may ask them straight away if you can't come across an sb50. could even be a change from past models to present as outback did throw them much competition after i had bought my sb50.
  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    Re: 180watt evergreen/c60 controller

    If you are running a 12 volt system, you don't HAVE to put the panels in series with an MPPT controller, that is mainly to reduce wire losses.

    Essentially, with one of the digital MPPT controllers, you get around 95-98% of full power from the panels. 720 watts at 12 volts is just about the max for one of the 60 amp ones.

    Running as is, with a C60, you will get around 45% less - more than 6.95 amps but less than the short circuit amps (ISC).

    But basically you are losing nearly half your power.