The final piece for my system.. panels.. 12v or 24v..??

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  • Dill
    Dill Solar Expert Posts: 170 ✭✭
    #32
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    thanks for the clarification...good luck!
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #33
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Thanks..

    I am poised to grab 2 tommorrow (when they are scheduled to be available) and then 3 more on Thursday if my funds from PP get to my bank account quick enough (which I am hoping).. I may be able to squeak 6 panels out of my funds if everything magically aligns..

    If anyone beats me to the last 3 that I need, set them aside for me.. LoL...
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #34
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Um.. dumb question..??

    I'm guessing if I put all the panels up.. say 500-800 watts of PV and only have 120 ah battery (to start with).. and have 6 separate breakers in the combiner box..

    I could just turn off some of the breakers feeding the controller as not to constantly FLOAT my battery, especially if I have no loads running..

    Do any of you folks do this type of thing?? turning off panels not needed... or shutting down all but 1 when you leave your offgrid cabins/homes..??
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #35
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    I leave all the panels connected over Winter, and disconnect the inverter.
    The charge controller should regulate the charge the battery needs. Higher current will charge faster, but there is such a thing as too much current (despite what some people may have told you). Fully programmable ones have the ability to limit current. Others will push all the current available (up to their max) as the battery needs. 800 Watts of panel could push more than 60 Amps on a 12 Volt system, and that's far too much for 120 Amp hours. Even half that would be high. You can disconnect the "extra" panels if you want; they won't suffer.
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #36
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Thanks Cariboocoot.. I'll have to experiment with the setup when the time comes..

    Hopefully things work out so I can get 725 (558 @ 77% eff) or the 870 watts (669 @ 77% eff) worth of panel..

    That way when the time comes, and I have like 400ah of 'bank' I can easily do my 5K Air Conditioner thing of 52 amps/hour and break even with the panels coming in and maybe not use a lick off the batteries during 'peak' sun hours.. :cool:

    The panels are rated at 18.7 VMP and 7.75 IMP.. 6 in parallel would be 46.5 amps.. (The are 22.3 VOC and 8.37 ISC.)
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  • Dill
    Dill Solar Expert Posts: 170 ✭✭
    #37
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Al, FYI, you need to clear out your PM box, it's full.
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #38
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    After much adoo and small discussions..

    I grabbed 3 of the 145 DMSolar panels off Amazon for $140 each shipped on Tuesday.. Amazon shipped all 3 Wed..
    These are Sold By DM, but Fulfilled By Amazon (for peace of mind)..

    If you order make sure your mark the free super saver 5-8 days option.. ;)

    This morning I woke up and the ppal cleared to my bank so I ordered 3 more of them for a total of 870 watts for $840.. :cool:

    The specs are:

    STC 145
    VMP 18.7
    IMP 7.75
    ISC 8.37
    VOC 22.3

    I plan on doing a video review of the panel mid next week when the get here..
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  • nsaspook
    nsaspook Solar Expert Posts: 396 ✭✭✭
    #39
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    You just busted my budget. I'm ordering a few myself.
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #40
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    I hear you.. they upped the price overnight to $160 shipped now.. $1.10/watt.. not as good as $0.97/watt but still pretty good IMHO..

    My first 3 are due Wed.. the next are shipping soon..
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #41
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Well I will be starting at 5 panels and 725 watts.. which still isn't shabby..

    Amazon gave me FREE 1 day shipping on the 1 panel (be here Monday).. and FREE 2 day shipping on the last panel (ordered late yesterday) to offset the $20 increase and the botched order disaster.. I'm sure shipping via Fedex a 26# solar panel probably cost way more than that $20.. LoL.. even the 2nd day service isn't cheap either..

    Amazon also gave me a $25 credit.. so I bought a Killawatt meter for $25.64 and free shipping.. and they covered the entire $25.64.. so I get a free killawatt meter so i can test my intended items for usage on the system.. and maybe get a grip on true numbers..

    I took the saved $140 (from not getting panel #6) and bought the MS meter front for the TS45 controller I got.. was only $90 shipped.. overall I feel ok with my choices..

    Last thing I will need is the Xantrex SW2000 Sine Inverter and 5 * 30' cables to wire the panels to the combiner box.. That will be late next month.. no funds for a few weeks..

    Will do a solar panel review and system update when things move along..
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #42
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    I got rid of the big ANL fuse holder (I hated the blockiness).. cut a new 3/0 wire off the wad my in-law has laying here.. ordering the BlueSea Fuse Block #5191 ($20) and a 250 amp fuse ($14) that goes right onto the terminal studs.. it will make it look neater and looks less likely to FAIL..

    PositiveWireUpdate.jpg

    blue_sea_5191_fuse_block_7893big.jpg

    I did keep the old wire as a spare with the ANL still mounted and the lugs intact..
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #43
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Panel #1 came in via Fed Ex overnite.. (was free upgrade for the order fiasco).

    145wattP1.jpg

    I have a thread running here on just the panels..

    The panels have a nice 1 3/8" frame on them.. pretty sturdy at 26 lbs..

    I have another 1 tommorrow (again Fed Ex overnite) and then 3 on Wed via UPS Ground..

    Wish I had an MC4 wire to try one.. figures I'd buy the panels and no wire (for 2 more weeks).. duh..
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  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    #44
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    I'll send you some MC4 'pig tails' if you want them.

    I purchased some 50' wires on Ebay that had soldered connectors on UL wires, so I cut off the 49' and will add the correct connectors and save the soldered connectors with 6-8" to do testing. Just PM me your address.

    That said, you can use the probes and test off the MC4 connectors.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #45
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Thanks Photowhit.. that would be great.. the panels has 3' of wires with MC4 connectors on them.. but 2 small wires with MC4's for testing the panels and mocking up to the TS45 would be great.. then I can see what I would possibly get in terms of AH, wattage, and such..
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  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    #46
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    As to what you will actually get from the panels your better off using the IMP ratings and figure @90% max. Your VMP will not be of great concern since your using an PWM CC, any reading you get will be an open curuit reading and of little value. It is nice have these just to help trouble shoot things, checking for continuity, or very different readings might point to panel issues.

    As to the panel label being different from the on line specs, that isn't too unusual, they typically match cells and the panel figure will vary, I think for the most part each batch of panels I've gotten have been the same(or vary close) but I'm not sure any have matched the advertised specs.

    I'll likely not get to town until Thursday, but I should be able to send them out then.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #47
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Changed my combiner box wiring to 6 AWG from the 8 AWG I had going to the charge controller..

    0.76% drop (with 6 AWG) is better than 1.21% drop (with 8 AWG).. (when carrying 45 amps)..

    combinernew6.jpg


    @ Photwhit..

    I got 6.32 amps at the panel this morning in sun (not at proper angle however).. it was climbing slowly..

    I did come up to 21.4 volts (again at the lead end of 3' of cable)

    The numbers on the panel are 18 VMP and 8.05 IMP..

    So you saying use 7.245 (90% of the 8.05) for the IMP and multiply by 18 for my panel wattage at the controller 15' away??

    That would be 130 watts.. which isn't bad IMHO.. the mfg claims a 17% eff.. but I checked the solar cell mfg site and it says 16.4% eff.. which would be about 121.22 watts (unless I figured that number incorrectly)..
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #48
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    I ordered a TriStar meter front on EB.. and I guess the seller ran out (or screwed up) and sent me the REMOTE meter (new in sealed box) for the same $90 shipped.. not complaining..

    METERTS45.JPG
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  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    #49
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Yes I think I would like that!!! And I wouldn,t complain either. solarvic
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #50
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    3 more panels just arrived.. checked voltage (VOC).. at 21.5-21.6.. back says 21.6 for VOC..

    3PkPanels.jpg

    215VOCPanels.jpg

    1 more coming via Fed Ex (from yesterday).. then I will be at 5 and 725 watts of PV..
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #51
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Just an Update.. Well I got 1 panel hooked up for testing.. (if you haven't noticed my other threads)..

    20.6 DC Voltage reading seems to be the normal readiing on the actual charge controller terminals.. :cool:

    This was with 5' of MC4 wire and from the 3' panel lead wires (total 8') and another 18" of 6 AWG from the combiner box to my TS-45 (PWM) controller..

    I was getting 110-112W and 7.6 Amps thru to the battery on initial testing 2 days ago...

    Heres a shot today with overcast in NJ.. 14.4V 7.0 A 101W and 99% PWM..

    101w7amp.jpg

    The meter I noticed shows 15.7 V under the solar voltage diagnostics tab.. (I suspect that has to do with the LOAD required for the battery..)

    2nd test MC4 wire hopefully tommorrow or Wed.. and I can test 2 panels on the system and see how the numbers go..

    Stay tuned..
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #52
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Well I dragged back another 145w panel to the house from storage..

    The battery started today at 9.6VDC (according to the meter).. (just enough to start the MS Controller)..

    Today at 11:30 am with lots of clouds and just 55 watts on the front.. Its 78' F outside..

    I skipped thru to the Solar Voltage (under diagnostics) and get this as input on the meter: 17.6V :cool:

    176VoltSolar.jpg

    Waiting for 12:30 to 1pm and try and do a 2 panel video for Y'all..
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,439 admin
    #53
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Note that 9.6 volts is "Dead Battery" and usually will mean that this battery is no longer any good. Will need replacement when you "go on-line".

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #54
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Yes.. I had mentioned prior about the + terminal being blackened.. and totally DOA'ish..

    What I learned today.

    PWM makes getting a reading a PITB..

    I had good solar voltage according to the meter.. but it kept it at 4.1-4.5 amps with 2 panels ON..

    That is definatley regulating the panels down to what it needs (14.4v) and thats it..

    IM000021.JPG

    Solar Voltage had peaks of 18.XX volts

    IM000023.JPG
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #55
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    I checked the panels each..

    Got 20.7 at the entrance to the combiner when breaker was OFF for each panel..

    Got 19.2 at the entrance to the combiner when BOTH breakers were ON for each panel..

    Got 17.1 at the entrance to the combiner when ONE breaker was ON..

    At the terminals inside the charge controller I got

    17.0 Volts with 1 panel on

    19.1 Volts with 2 panels on

    The amperage went DOWN 2/10's of an amp when I would switch off one panel or the other..

    So confusing..

    Its got to be SHOWING me only what the battery must need and not really the output on the screen..

    Even at 17.X V I figure at 4.1 amps I'm getting only 70 watts per panel and maybe thats because of the weather with the clouds..

    I dunno.. I know each panel works from last weekends testing..
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,439 admin
    #56
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Clouds, shadows (when sunny), and a DOA battery will all serve to limit output power...

    If the battery voltage is at 14.x volt setting of the controller, then it will start cutting back on current from the solar array.

    And DOA batteries frequently have fairly high resistance/poor chemical conversion, so they reach "absorb voltage" fairly quickly--If they did not, then they would probably be taking a charge (assuming no shorted cells).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #57
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    Re: The final piece for my system.. panels.. 12v or 24v..??
    ywhic wrote: »
    Got 20.7 at the entrance to the combiner when breaker was OFF for each panel..
    Got 19.2 at the entrance to the combiner when BOTH breakers were ON for each panel..
    Got 17.1 at the entrance to the combiner when ONE breaker was ON..

    At the terminals inside the charge controller I got
    17.0 Volts with 1 panel on
    19.1 Volts with 2 panels on
    The amperage went DOWN 2/10's of an amp when I would switch off one panel or the other..

    So confusing..

    There's nothing confusing or surprising about this: it is exactly what would happen.

    Neither panel connected: reading Voc 20.7 from panels.
    Both panels connected: Voltage is pulled down by load to 19.2
    One panel connected: Voltage is pulled down by load to 17.1 (less power from one panel to keep Voltage up).
    Amperage goes down when either panel is disconnected for the same reason: less power available from panels to keep the current high.

    You absolutely can not expect to see any real performance figures based on feeding two imperfectly aligned panels into a dead/sulphated battery.

    For your own peace of mind, wait until you have it all together before trying to judge its performance. I walk past my controller 50 times a day, and at no two of those times will the input or output numbers be the same. I don't worry about it at all, because over the course of the day it works: the batteries charge.

    Or at least they would if it would stop raining. (Starts thinking about micro-hydro downspouts again. :p )
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #58
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Thanks.. thats what I figured.. I'm getting a 4+ amp reading from either panel individually and the voltage seems great on both..

    Just doing a further review for anyone watching this thread..

    It says 7.9 AH on the meter so I'm gathering that part is working.. LoL..

    A better TEST battery will be needed I suppose..

    But I think I am done playing.. time to go get a JOB..
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  • Dill
    Dill Solar Expert Posts: 170 ✭✭
    #59
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    Re: The final piece for my system.. panels.. 12v or 24v..??
    Cariboocoot wrote: »
    There's nothing confusing or surprising about this: it is exactly what would happen.
    I walk past my controller 50 times a day, and at no two of those times will the input or output numbers be the same. I don't worry about it at all, because over the course of the day it works: the batteries charge.

    ditto, and I'm lucky if I do a 'function check' every couple of months. I leave my battery monitor on the % batt display, and if it hits 70% then I pay attention. Otherwise, I just keep on a-walkin!
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #60
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    Re: The final piece for my system.. panels.. 12v or 24v..??

    Yes the battery must be totally shot..

    I shut off the panels after 3 hours and it says 13.5V and 0 amps..

    When the juice from the panels is on it creeps upto 4.12 Amps.. LoL..

    Knida hard to get a 'read' on a junk battery..

    Video..

    [video=youtube_share;GHS-3Yt53Qw]http://youtu.be/GHS-3Yt53Qw[/video]
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  • ywhic
    ywhic Solar Expert Posts: 621 ✭✭
    #61
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    Re: The final piece for my system.. panels.. 12v or 24v..??
    Cariboocoot wrote: »
    Amperage goes down when either panel is disconnected for the same reason: less power available from panels to keep the current high.

    Actually with 2 panels I was at 4.3 AMP reading.. then with 1 panel only it dropped for a second then came back up to the same 4.4 amps??

    I had 53% PWM with 2 panels ON.. then with just 1 panel ON it went to 87% PWM..

    The watts and amps shown really didn't change except for a minute and then re-leveled..

    Why did the PWM % number go UP to 87% (from 53%) when I turned OFF 1 panel??
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