Deciphering my remotes display (MT50)

redunculousredunculous Registered Users Posts: 22 ✭✭
I cannot seem to find this in the remote Manual but can anyone tell me what the reading is below the battery image? I have an MT50 and it's showing 1.1 under solar panels, 2.9 under battery?

On that note, if 1.1 is my current amp input from the panels it seems quite low for 2 x 100 watt wired in series? Suns out in force here in Florida right now - have I done something wrong?
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Comments

  • littleharbor2littleharbor2 Solar Expert Posts: 1,494 ✭✭✭✭
    edited June 2017 #2
    A photo would help. If your batteries are nearing full they will only accept so much amperage. You take advantage of the unused potential power by running loads in the daytime when the batteries are full or nearly full.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • littleharbor2littleharbor2 Solar Expert Posts: 1,494 ✭✭✭✭
    edited June 2017 #3
    That appears to be right. Higher voltage when converted to lower will increase the amperage. That's the beauty of MPPT controllers. Although the numbers on this meter aren't a very good example as the incoming voltage is basically a 12 volt panel charging a 12 volt battery.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • redunculousredunculous Registered Users Posts: 22 ✭✭
    Here is a picture

    So what I am seeing is the amount the solar is passing to the batteries? Makes more sense, how do I see what they are actually producing, is that possible?

    The part that confused me (well alot of it does right now!) was the low amps I am seeing from the panels (makes sense if its just what is being fed to the batteries) and the amp under the image of the battery (2.9)\

    thanks for the help - really appreciated

     i
  • littleharbor2littleharbor2 Solar Expert Posts: 1,494 ✭✭✭✭
    As you can see the battery is full. It can only accept so much amperage when in this state. When you are down to 60-70% and in bulk charging mode your batteries will take everything your panels can give.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • nickdearing88nickdearing88 Registered Users Posts: 100 ✭✭✭
    I think what the OP was asking is: Can I see how much "potential power" is available? If the batteries/loads were drawing more current, how much would be available for opportunity loads. I don't think there is a way to display this, but I agree it would be awesome for many end-users.
    Current system: 8-100w Renogy panels mono/poly, 2 strings of 4 panels in series - 24v 100Ah AGM Battleborn LiFePO4 batteries - Morningstar MPPT40 CC - 1500W Samlex PSW inverter
  • redunculousredunculous Registered Users Posts: 22 ✭✭
    So what is the amps under the battery image - can't be a load amount as nothing is running that would need that amount.

    Nick - that is what I was wondering it would be good to see my panels capability so I know they are running optimally
  • EstragonEstragon Registered Users Posts: 4,460 ✭✭✭✭✭
    It looks like the controller may be in absorb mode at 14.5v (pretty high for float), so it's putting the power into the battery. You should see something like 4a out of the panels when the controller is in bulk.
    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
  • LumisolLumisol Registered Users Posts: 374 ✭✭✭
    You have 37.2v @1.1amps being converted by the controller and fed into the battery at 14.4v @2.9amps as shown by the numbers and arrows. There is no load (no arrows) and no amps but a voltage of 14.5 v is available for loads.
  • SolraySolray Registered Users Posts: 246 ✭✭✭
    Whether or not you did something wrong cannot be deduced from the display alone. What are the ratings of the panels specifically.
    It sounds low for the panels to be at that level though. How are they mounted? Is there air under them to help cool them? Are all the connections good? What is the voltage at the panels reading?
  • EstragonEstragon Registered Users Posts: 4,460 ✭✭✭✭✭
    OP can tell a lot from the display alone. If he gets 4-5a at ~ 37v out of the panels with good sun in bulk, the panels are doing about what I'd expect.

    Whether that's enough for charging, loads, etc depends on stuff we don't know.
    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
  • littleharbor2littleharbor2 Solar Expert Posts: 1,494 ✭✭✭✭
    Try this, shut down the solar to the controller. Allow your battery to discharge into the 60 -70 % SOC, turn it back on at mid day and see what you are getting for amperage.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • redunculousredunculous Registered Users Posts: 22 ✭✭
    When I tested them I was seeing 40 from each panel - I will be honest I do not know how to actually test them so I was just playing with my voltmeter and that's what popped up

    They are mounted to breathable canvas on top of my boat - if I need to elevate them slightly I believe I can do will do that but I would expect them to be able to breath like that and the air as I sail should be pushed under neath them from the front as thy are held down along the sides only.
  • littleharbor2littleharbor2 Solar Expert Posts: 1,494 ✭✭✭✭
    edited June 2017 #14
    40 volts would be the open circuit voltage of both panels in series. There doesn't seem to be anything wrong here. One thing though. When series wired, any shadow will substantially affect the panels output as they are essentially one panel. Do whatever necessary, including relocating them to avoid shadows. While the shot of your MT-50 is self explanatory showing your battery almost totally full, hence limiting amperage acceptance into your battery you will have similar low amperage output from shadowing.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • EstragonEstragon Registered Users Posts: 4,460 ✭✭✭✭✭
    I wouldn't worry about raising panels off canvas.

    The series connection thing could be an issue on a sailboat though. A shadow from the backstay across part of a panel could significantly reduce production. If it looks like it might be a problem, I'd rewire the panels in parallel to see if the mppt controlller is ok with the voltage in your ambient temps. If not, I'd consider a pwm controller.
    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
  • redunculousredunculous Registered Users Posts: 22 ✭✭
    Thank you all

    Will see how it goes when we are sailing and if we have a shadow issue!
  • EstragonEstragon Registered Users Posts: 4,460 ✭✭✭✭✭
    Fair winds :-)
    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
  • SolraySolray Registered Users Posts: 246 ✭✭✭
    Fair winds and following seas, to be precise. :)
  • redunculousredunculous Registered Users Posts: 22 ✭✭
    Estragon said:
    OP can tell a lot from the display alone. If he gets 4-5a at ~ 37v out of the panels with good sun in bulk, the panels are doing about what I'd expect.

    Whether that's enough for charging, loads, etc depends on stuff we don't know.
    Thanks for the fair winds and following seas comments guys! 

    We are now into our sailing trip (having a blast) and the most I have seen off this install is 5amps

    Is that sounding right for 2 panels wired in series? I for some reason thought I would be seeing a minimum of 8amps (4 off each panel) 
  • westbranchwestbranch Solar Expert Posts: 5,183 ✭✭✭✭
    edited July 2017 #20
    redunc, please fill in a signature line... I can not  find what PVs you have ...
     
    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,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • redunculousredunculous Registered Users Posts: 22 ✭✭
    edited July 2017 #21
    redunc, please fill in a signature lie... I can not  find what PVs you have ...
    I am quite an idiot with the internet it seems, not sure what a signature lie is?

    PV's i"m guessing are solar panels? So sorry if wrong

    We are running

    2 x 100watt semi flexible wired in series 
    EPEVER MPPT Controler
    MT50 remote
  • EstragonEstragon Registered Users Posts: 4,460 ✭✭✭✭✭
    Wiring in series increases voltage, current in amps stays the same.

    Put another way, two panels might put out 5a at 37v = 185w wired on series. The same panels wired in parallel might put out 10a at 18.5v = 185w. It's a bit more complicated because of wire losses vs controller efficiency etc., but that's the concept generally.

    Glad you're having fun out there, and keepin it safe!
    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
  • redunculousredunculous Registered Users Posts: 22 ✭✭
    Thank you for that

    Am I better off putting these in Parallel then? If I can achieve 8-10 amps at peak sun times I am on track for keeping my batteries charged with my usage. The most intensive items that run are our fridge and freezer - which draw around 8amps combined when the thermostats kick in. The rest is minimal and barely touches an amp when we are sat at anchor.
  • redunculousredunculous Registered Users Posts: 22 ✭✭
    edited July 2017 #24
    Perhaps I am slightly confused about it all.

    My battery charger when plugged in to the dock power (110) is pushing out a vast number of amps and the most voltage it puts out is 14.4 for LA batteries (to stir them up etc when required), is there a reason I wouldn't want to wire in parallel to achieve a greater amount of amps so I can balance my amp usage on the boat?

  • redunculousredunculous Registered Users Posts: 22 ✭✭
    edited July 2017 #25
    Crap now I may have just had the lightbulb moment

    If I have them in parallel the most I will ever see volt wise is 12v which is not enough to keep my batteries stable yes? I know I need to charge at a certain voltage as I just said it above. 

    So to get more amps, can I add another 100w and if so do I need to wire it in a certain way? Or do I now have to purchase two so I have them in series and parallel?

    Haha, the lightbulb has now gone out in my head as I just re-read yours and you guestimate 18.5v

    So surely for my needs parallel is the answer?
  • littleharbor2littleharbor2 Solar Expert Posts: 1,494 ✭✭✭✭
    The MPPT controller will boost the amperage as it steps down the voltage. You don't necessarily want your panels wired in parallel.
     

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • mcgivormcgivor Solar Expert Posts: 3,299 ✭✭✭✭✭
    edited July 2017 #27
    Using series  is the better choice, in parallel there may not be enough headroom for the MPPT to operate correctly, generally about double or more than the nominal voltage is required. So adding 2 more panels  in series  parallel would be the best solution, in my opinion.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • EstragonEstragon Registered Users Posts: 4,460 ✭✭✭✭✭
    Having them in parallel will give you twice the current with panel voltage (~18v depending on temperature, not 12v). As mentioned, with an mppt controller, having panels in series likely works out better. With a different type of controller (pwm) having them in parallel might make more sense. In your case, with an mppt controller and shade not a problem, I'd say stick with series.

    When plugged into shore power, you have a functionally unlimited current (roughly 150a on a 15a/120v plug), and your batteries will take what they take. Below about 80% state of charge, that will be around 20% of capacity for flooded. That would be ~ [email protected] with a 200ah bank.

    2x100w panels might put out ~150/14.5v charging=10a into the batteries.

    On my boat, I find the fridge takes a surprising large amount of power. It's an oem icebox retrofitted with a 12vdc compressor and evaporator, which uses around 75-100ah/day, depending on ambient temps, and whether I put a block of ice in to keep cold etc. Taking 100ah out of my 200ah house bank means I'm down to a 50% state of charge, which, with 8-10a solar and no loads, would take all day to get back to about a 90% state of charge, and another couple hours to get to full. With shore power at 40a, it would take 2-3 hours, plus another couple to get to full.

    With no loads or charging sources for a few hours, you can roughly guess your battery state of charge. 12.8ish is full. 12.2ish is around 50%. Anything under about 11.7 means you're running on fumes. My suggestion would be to get a sense of daily consumption and how close you normally get back to a full charge, and go from there.
    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
  • westbranchwestbranch Solar Expert Posts: 5,183 ✭✭✭✭
    edited July 2017 #29
    Redunc...  to clarify, if you have 2 PV panels in PARALLEL you will get the Vmp voltage (on the makers spec plate, usually on the back of a PV panel) and you will get the sum of the Imp (amperage) shown on the panels  (2 x Imp)  if the panels are identical however
    when the  panels are in SERIES you will now get the sum of the 2 Panels Vmp ( 2 x Vmp) but only the Imp of 1 panel....  you can use the same formula for more panels just use the number of panels you have...
    so  In SERIES add Voltage
    and In Parallel add Amps
    The total watts will be the same.
    hth

    oh, that should have been Signature LINE not lie, spell check accepts both as correct spelling... ooops
     
    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,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • redunculousredunculous Registered Users Posts: 22 ✭✭
    I'm starting to feel a bit stupid here so I am sorry for the following question... I thought I had a good amount of knowledge about power but clearly I do not!

    Surely I would be better off pumping 10 amps into my batteries rather than 5, especially if my voltage is over the magical 14.4 and can 'boost' when required? If I am drawing around 8 amps on and off from my fridge and freezer during the day, 10 amps from my solar would keep me most likely ahead of the game (I'm currently sat on the boat in the bahamas so we have tons of sun). As I am only see 5 amps peak I am watching my batteries slowly deplete and have to run a small generator daily.

    Again - please dumb this down for me as I re-read the posts that you guys have written clearly with great knowledge (thank you for the indepth responses) but my brain cannot seem to grasp why I wouldn't want the 10amps over 5 to recharge my batteries

    On a side note, Estragon are you able to insulate your system more? We are waiting on a delivery here of some stuff called Reflectix? Its a wrap around insulation, we are going to do our boxes on sunday when it arrives and see if it drops our amp usage further - we hope it will.
  • westbranchwestbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Yoou need to start thinking in watts in and out of your system... 2 pv's produce 100 W each , so you have 200 watts total, max less inefficiencies... 200W that is all regardless of how many amps the mppt CC is reporting! The mppt plays with the Volts and amps to charge your 12 volt battery at about 14 to 15 volts, so thinking Watts now how does it get those volts? It uses mppt magic to get the volts needed and to do that it decreases the Amps avaiable... ie it is no longer 10 amps it is likley somthing less than 5 due to system inefficiencies.
    Hth
     
    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,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
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