XW MPPT-150 60A Solar Charge Controller/Regulartor

Team

I have (2) XW/Scheider solar controller, these are 4 wire feed. I noticed amperage readings are not acurate or even close to the reals. I have read here a similar situation but dont get the correct answer.

For example:

I have a 48 battery bank and 2.1KW solar array plus a XW 6048 inverter in a power panel setup

PV amperage being read by a DC clamp meter. It reads 29A before and after the solar regulator ( In a 78Voc system )

XW solar controller/regulartor read like 2.9A. The shunt circuit in XW controller could be bad or is bad wiring and the -PV needs to me married with -Batt?

Something is wrong here

Thanks

Comments

  • BB.BB. Super Moderators, Administrators Posts: 31,171 admin
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Hmmm... In general, the present crop of Xantrex production line seemed to have pretty accurate reporting of voltage current.

    You are correct, the newer XW MPPT controllers (at least the 150 VDC version) is a four wire device. You have to have the + and - leads attached to the respective MPPT controller. You cannot (for example) common bus the - PV Array leads together. The XW measures the array current on the negative lead and if you common bus the negative array leads, it will mess up the controller's measurements/MPPT calculations.

    Many (most?) other brands of MPPT and PWM controllers can common bus the PV Array negative leads directly to the battery bank. As I understand.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SkiDoo55SkiDoo55 Solar Expert Posts: 414 ✭✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Question what is the arrangement of your solar array. Panel spec? Panels in each string, number of strings. Number of strings on each charge controller. As shown in manual + & - from array should be in respective input connector. Output +& - should not be connected to the input connections. Charge controllers should not be connected to a common array for MPPT to function correctly.
    GT3.8 w/4600W Trina 230W, TX5000 w/5000W ET-250W, XW4024 w/1500W ET-250W, 4 L16, 5500W Gen. (never had to use) Yet!!
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Hi Bill.

    These (2) [email protected] are brand new, one is Xantrex and the other is Schneider. They are in excellent conditions, not abused I recently upgrade my setup, I was using a SW4024 with the XW-MPPT-150, a 78Voc but down to 24V. the current was noticeable in the display, but now with the new set up with 48V inverter and battery bank the display amperage reading feels out of scale somehow.

    Here is my current setup:

    48V GNB Absolyte II AGM battery bank 1495Ah
    (1) XW6048 inverter
    (1) XW power panel
    (1) [email protected] Xantrex " faulty current (A) readings , not real "
    (1) 2.1KW solar array , 78Voc
    (1) [email protected] Schneider ( future 2.1K solar array upgrade ) behaving like the Xantrex

    All the wiring from the PV arrays, -PV & +PV ends in one [email protected] Xantrex, then -Batt & +Batt accordingly. Not common negative bus. It does reads current but very low as well the wattage shown, but there is real current flowing through the cable as expected. I tried the Schneider model new from box, did the same. Looks like they don't like a 48V battery bank.


    Raul
    Puerto Rico
  • SkiDoo55SkiDoo55 Solar Expert Posts: 414 ✭✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Do you have voltage in and out with the current readings. What is the display showing Volts/Amps for in/out. Sounds like a wiring, low voltage from PV Array issue if 2 separate controllers are doing the same thing. May consider resetting to factory defaults and re-initializing the controller and check all of the settings are correct. I know that should not effect amps reading. Check your amp clamp on known current draw. Seems strange to have same current in and out at the same time and be one decimal place off? On difference charge controllers. Simple things can cause lots of troubles.

    Array configuration will help in seeing if that is an issue for 48 VDC operation. Panel model also.
    GT3.8 w/4600W Trina 230W, TX5000 w/5000W ET-250W, XW4024 w/1500W ET-250W, 4 L16, 5500W Gen. (never had to use) Yet!!
  • BB.BB. Super Moderators, Administrators Posts: 31,171 admin
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Raul,
    Hi Bill.

    These (2) [email protected] are brand new, one is Xantrex and the other is Schneider. They are in excellent conditions, not abused I recently upgrade my setup, I was using a SW4024 with the XW-MPPT-150, a 78Voc but down to 24V. the current was noticeable in the display, but now with the new set up with 48V inverter and battery bank the display amperage reading feels out of scale somehow.
    ...
    48V GNB Absolyte II AGM battery bank 1495Ah
    (1) 2.1KW solar array , 78Voc

    78 Voc is a bit low for a 48 VDC battery bank... Your Vmp-array should be at leat 72 volts which would make Voc~88 volts.

    Your Vmp-array at standard temperature/test conditions would be around 63 VDC, and in hot weather would be closer to 54 volts. The Charge controller and wiring would eat another couple volts, so the charging voltage available to the battery would be close to 52 volts--Which would be ~float voltage (very rough guesses).

    Ideally, you need to get that solar array voltage up... Depending on how cold it gets in your region, the maximum Vmp-array would be around 100VDC (to high, and Voc-cold would be too high and could damage the controller).

    If the controllers work OK on a 24 volt battery bank--Then I would guess everything else is OK.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.BB. Super Moderators, Administrators Posts: 31,171 admin
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    I have to go right now, but you should be looking at a range of 5% to 13% or so for charging current for that bank.

    The minimum charging current/array for a cycling battery bank would be:
    • 1,495 AH * 5% = 74.75 Amps minimum
    • 1,495 amps * 59 volts charging * 1/0.77 panel+controller deratings * 0.05 rate of charge = 5,728 Watt array minimum

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor
    SkiDoo55 wrote: »
    Question what is the arrangement of your solar array. Panel spec? Panels in each string, number of strings. Number of strings on each charge controller. As shown in manual + & - from array should be in respective input connector. Output +& - should not be connected to the input connections. Charge controllers should not be connected to a common array for MPPT to function correctly.


    SkiDoo55:
    Right now:

    (1) array 2.1KW

    (3) strings of 4 Sharp NT-175U1 panels combined in series/parallel per 2 modules per string to obtain 88.8 Voc, or 70.8 Vpm with 11.9 Ipm per string.


    PV wire are combined in parallel a Midnite MNPV3 then a DC disconnect per NEC, then straight to Xantrex [email protected] charger regulator. -PV, +PV respectively, then -Batt, +Batt as it should be.

    Controller shows a very very low amperage reading compared with a DC clamp meter.

    Raul
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor
    BB. wrote: »
    Raul,



    78 Voc is a bit low for a 48 VDC battery bank... Your Vmp-array should be at leat 72 volts which would make Voc~88 volts.

    Your Vmp-array at standard temperature/test conditions would be around 63 VDC, and in hot weather would be closer to 54 volts. The Charge controller and wiring would eat another couple volts, so the charging voltage available to the battery would be close to 52 volts--Which would be ~float voltage (very rough guesses).

    Ideally, you need to get that solar array voltage up... Depending on how cold it gets in your region, the maximum Vmp-array would be around 100VDC (to high, and Voc-cold would be too high and could damage the controller).

    If the controllers work OK on a 24 volt battery bank--Then I would guess everything else is OK.

    -Bill


    Right now I have (12) Sharp NT-175U1 solar modules installed as one array. They are wired series then parallel per string. This is Voc of 88.8V, Vmp of 70.8V @ Imp 9.9A per string of 4. I have 3 strings. Are you with me? Ok...

    Maybe I mistaken the Voc or Vmp values. Indeed is Voc 88.8v and Vmp 70.8. Do you think is low? The big headache I have is ( only have (2) [email protected], one of them is not connected yet, is for the future 2.1KW upgrade array #2) they only accept a maximun Voc of 140V. If I wired all panel in series I will end with a Voc of 177.6V, not good for MPPT-150

    Then I might have to wired (3) panel in series for Voc of 133.2V/per string and do (4) strings then.... I will end with Voc of 133.2V @ Imp of 19.8A using (12) Sharp 175WU1 right?


    I'm not net metered yet , the inverter is on Grid Support mode and backup, it kicks in above 52V for GridSupport.




    I do have (12) new same modules at my garage to be installed over the weeked, this is the 2nd array.
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor
    BB. wrote: »
    I have to go right now, but you should be looking at a range of 5% to 13% or so for charging current for that bank.

    The minimum charging current/array for a cycling battery bank would be:
    • 1,495 AH * 5% = 74.75 Amps minimum
    • 1,495 amps * 59 volts charging * 1/0.77 panel+controller deratings * 0.05 rate of charge = 5,728 Watt array minimum

    -Bill

    Excellent info Bill. Will be taken in consideration. What you will do with my setup?

    (24) Sharp 175U1
    (2) XW charger controller
    (1) 6048 inverter
    (1) 1495Ah battery bank, can be configured to 48V or 24V ( 24 x 1.2V/cell @1495Ah )

    My NREL sun irradiation is 5.3hrs average



    I have a power comsuption of 575 KWH/month average

    Raul
  • SkiDoo55SkiDoo55 Solar Expert Posts: 414 ✭✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    For the 12 panels Sharp NT-175U1 sure you don't have them in 4 strings of 3 ea modules? Module spec is VOC @ STC = 44.4 V. Tool gives 148 VDC @ VOC nearing max VDC for controller. Will probably be lower after correcting for your local low temp.

    Would need your high and low temps to further refine.
    GT3.8 w/4600W Trina 230W, TX5000 w/5000W ET-250W, XW4024 w/1500W ET-250W, 4 L16, 5500W Gen. (never had to use) Yet!!
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor
    SkiDoo55 wrote: »
    For the 12 panels Sharp NT-175U1 sure you don't have them in 4 strings of 3 ea modules? Module spec is VOC @ STC = 44.4 V. Tool gives 148 VDC @ VOC nearing max VDC for controller. Will probably be lower after correcting for your local low temp.

    Would need your high and low temps to further refine.


    No.. right now they are not as 4 string of 3 modules for a total of 133.2Voc @ Imp 4.95A /string.

    They are 3 string of 4 modules for a total of 88.8Voc @ Imp 9.9A/ string
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor
    No.. right now they are not as 4 string of 3 modules for a total of 133.2Voc @ Imp 4.95A /string.

    They are 3 string of 4 modules for a total of 88.8Voc @ Imp 9.9A/ string



    Temp here is 76F low, 92F high average/year, this is caribbean temp the whole year
  • SkiDoo55SkiDoo55 Solar Expert Posts: 414 ✭✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Need to reconsider that
    4 modules X 44.4 VOC/STC = @ 177 VDC @ 4.95 amp per string
    3 modules X 44.4 VOC/STC = @ 133 VDC @ 4.95 amp per string your 76deg min temp.

    4 strings @ 4.95 amp per string = 19.8 amp DC
    Vmp at Pmax will be @ 106.2 VDC
    Charger output at Pmax will be @ 38 amp STC rating derate for temperature, 33 amp PTC conditions.
    With 3 modules in series min VMP at max temp will see @ 87 VDC

    Should be able to see what the controller is doing on the "Meters" page on display, voltage&amps in/out to compare.
    GT3.8 w/4600W Trina 230W, TX5000 w/5000W ET-250W, XW4024 w/1500W ET-250W, 4 L16, 5500W Gen. (never had to use) Yet!!
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Ski,

    In my case 3 string of 4 modules for a total of 88.8Voc @ Imp 9.9A/ string, the issue is not the design is the XW amperage meter not showing the real amp reading. BB said the PV voltage is too low, ok but doing some testing with a DC clamp meter before and after the XW charge controller and the current is basically the same techinically speaking.

    Buy my bad, my bad, my bad, how I missed this detail!!! I just checked again and I have the -PV connected to the -Batt bus bar, is not connected to the XW shunt thorough the -PV terminals ( make sense, is like 0 Ohms, is a shunt.

    Keep you posted.

    Thanks all, feels like in home

    Raul
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Problem solved!! The -PV was connected to -Batt bus bar.


    Raul
  • BB.BB. Super Moderators, Administrators Posts: 31,171 admin
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor

    Glad you found the problem... And it was simple to fix.

    Monitor the array voltage. 2*35.4 volt Vmp = 70.8 volts Vmp-array is a bit on the low side but may be OK. If it does not get too hot there, you may be OK with just two panels in series. Too low of Vmp-array will not hurt anything--it will just limit your array's output current/power on very hot days.

    Just watch the total power from your array on hot days--If you get your expected power, then don't worry about it.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • MasterSolarPRMasterSolarPR Registered Users Posts: 15 ✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor
    BB. wrote: »
    Glad you found the problem... And it was simple to fix.

    Monitor the array voltage. 2*35.4 volt Vmp = 70.8 volts Vmp-array is a bit on the low side but may be OK. If it does not get too hot there, you may be OK with just two panels in series. Too low of Vmp-array will not hurt anything--it will just limit your array's output current/power on very hot days.

    Just watch the total power from your array on hot days--If you get your expected power, then don't worry about it.

    -Bill

    Good morning Bill

    Pueto Rico is hot, right now is 90F. All looks fine XW's charge controller is showing acceptable current readings.

    local time: 11:05am Easter time
    PV input : 72.63V
    DC in :13.14A
    DC outV :54.33V
    DC outI : 17.63V
    Inverter Load "GridSupport": 0.707KWH
  • jeffkrusejeffkruse Solar Expert Posts: 205 ✭✭✭
    Re: XW MPPT-150 60A Solar Charge Controller/Regulartor
    Temp here is 76F low, 92F high average/year, this is caribbean temp the whole year

    76? Where do you live? My setup was in San German. I live in Moca. I saw lows of 62 degrees a few times in early morning. I was/am at 550' of elevation.

    Also, unless your in the south sunny side you need to take local weather patterns into effect. I, and some co-workers see only an avgerage of 4.3 sun hours because of afternoon clouds.
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