tristar mppt parallel HELP

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Hi,I'm Walter,a new user.
I own 4 morningstar mppt 60 in parallel, I noticed that in the custom mode and also in fixed absorption mode they don’t go in float even after 180 minutes.
thanks
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,500 admin
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    Re: tristar mppt pallel HELP

    Welcome to the forum Walter,

    Can you tell us the charge controller voltage (and time, if any) settings you are using?

    Also, what is the battery voltage(s) when charging.

    It would also be nice to know more about your system (wattage/configuration of solar panels, battery bank AH rating, etc.).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
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    Re: tristar mppt pallel HELP

    And also let us know what loads are on your system while the controllers are trying to charge the batteries.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    I apologize for my english, I’m italian and i live in Milan. I added in parallel on my battery bank the 4th TS MPPT 60. I had already problems with 3 TS, but now they never go in float, they never read themselves mutually.

    I tried all the possible settings:

    off-off-on 2 - Sealed* 14.15 13.70 14.40 28
    off-on-off 3 - Sealed* 14.30 13.70 14.60 28
    off-on-on 4 - AGM/Flooded 14.40 13.70 15.10 28
    on-on-on 8 - Custom Custom Custom Custom Custom

    the 4 tristar are in parallel on the battery bank 1500A/48V(battey Midac OPzS 2Vx24), I don’t use meterHub because in the past it has struck by lightening one tristar
    The battaery has 6 australian megapulse in series

    Panel around 13kw

    Linked Tristar 12 monocrystal 260 wp
    Linked Tristar 15 policrystal 230 wp
    Linked Tristar 15 policrystal 230wp
    Linked Tristar 12 policrystal 230wp
    Inverter 8kw of goog chinese brand.

    When the set charge of 58V is reached, after 150 minutes from the absorption mode it should pass to FLOAT, but it continues staiyng for all the day in ABSORPTION.
    Can you tell me what’s the problem?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP

    Did I read that right? A 1500 Amp hour 48 Volt battery bank? Are you powering a small country? That's 36kW hours of stored power!

    13 kW array is massive too. Ought to supply about 200+ Amps or around 13% peak current.

    So let's look at that current: how much are you getting from each controller? And how much power (in Amp hours) is actually being drained from the batteries?

    The usual reasons for staying in Absorb all day are: batteries not being fully charged (in this case the potential is there unless the drain on them exceeds what can be put back in a day), Absorb ending specifications set wrong (as in minimum time too long or End Amps too low depending on if the controller has these functions), defective equipment.

    I will hazard a guess that for those batteries you would need to use the 'custom' settings, meaning each controller needs to be programmed with a computer and MS View software. Co-operation between them should be close enough even without the communication hub attached.

    You mention '6 Austalian Megapulse in series'. I'm going to guess that is some kind of battery desulphator. If so, remove them. Desulphators are known to sometimes confuse MPPT controllers. They are not known for being demonstrably effective on battery lifespan.

    Another thing you should do is check the actual Voltage at he battery bank and the controllers to see if there is any disagreement. Remote temperature compensation is a must in this case too, and without the communication hub that will require one sensor per controller. Buying a new hub might be cheaper.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    I’ll try to remove megapulse, but in costum mode I can’t do different settings, it’s impossible, I have already tried it.
    Do you know how to reset the tristar to give them the original settings? Should I use the Msview software?
    Hear you soon, thanks a lot

    Sorry I don't undestand this sentence: "Remote temperature compensation is a must in this case too, and without the communication hub that will require one sensor per controller. Buying a new hub might be cheaper." I already have a hub, should I connect it? The last time it struck with lightening one of my tristar
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP
    walter01 wrote: »
    I’ll try to remove megapulse, but in costum mode I can’t do different settings, it’s impossible, I have already tried it.
    Do you know how to reset the tristar to give them the original settings? Should I use the Msview software?
    Hear you soon, thanks a lot

    This does not make sense. With a TriStar set for custom configuration and connected to a computer running MS View software you should be able to pick your own parameters for battery charge set points.

    If you power down the TriStar (disconnect PV first, then battery) and place the DIP switches in the original configuration it should reset.
    Sorry I don't undestand this sentence: "Remote temperature compensation is a must in this case too, and without the communication hub that will require one sensor per controller. Buying a new hub might be cheaper." I already have a hub, should I connect it? The last time it struck with lightening one of my tristar

    If you have multiple controllers sharing data through a communication hub you would need only one remote temperature sensor to tell them all what temp the batteries are at. Otherwise each controller would need its own sensor to get the corrected Voltage. If you have no remote temperature sensor at all the Voltage is going to be interpreted incorrectly by the controller(s).

    If your hub was fried by lightning is is no good. A new hub may be cheaper than three extra temperature sensors. It sounds as though lightning arrestors on the arrays would be a good idea.

    You should also have the recommending charging parameters for those Midac batteries, as that is the goal here. The info supplied by the company may not meet with the way RE systems work, so some interpretation may be necessary.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    I have a functioning Hub, when I inserted it between two tristar it struck by lightning one of them and I had to re-buy it. Yes it’s true that in COSTUM mode you can give to each tristar a customized setting, but then the data would go in conflict if they are not set with the same parameters.
    Each tristar has already his temperature sensor, I don’t know Hub with a unique sensor from morningstar
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP
    walter01 wrote: »
    I have a functioning Hub, when I inserted it between two tristar it struck by lightning one of them and I had to re-buy it. Yes it’s true that in COSTUM mode you can give to each tristar a customized setting, but then the data would go in conflict if they are not set with the same parameters.
    Each tristar has already his temperature sensor, I don’t know Hub with a unique sensor from morningstar

    You will always set all of the charge controllers the same because they all are connected to the same battery bank. The custom settings allow you to tailor the charging to that battery bank specifically, rather than use any of the preset modes.

    If you have a communication hub you should be using it. There is no hub with its own temperature sensor; it allows all the controllers to share the information supplied by one sensor connected to one controller (the 'master' controller).

    You do still need to check the output current from each controller.
    You also need to check the amount of power being used against the amount of power being produced; if you use more than the panels can produce in a day the batteries will never finish Absorb regardless of settings.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    I have a Victron 602 that is monitoring the battery bank. I’m scared about connecting the MeterHub because I have already used it with two tristar end one of them went in short circuit.
    Now I have set in costum mode the 4 tristar and disconnected the Megapulse.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP

    It seems Midac is reluctant to give out important information about charging; I've just been looking over their site and could not find any such specifications. These appear to be flooded cells, not sealed or AGM, so the default setting of "off-on-on 4 - AGM/Flooded 14.40 13.70 15.10 28" is probably closest. I worry the Absorb Voltage of 14.4 may be too low.

    Now some operational theory.

    You have a 1500 Amp hour (possibly; the specs aren't clear on that either) 48 Volt battery bank.
    If you discharge it 25% that's 375 Amp hours or about 18 kW hours DC.
    Your 13 kW array should be able to produce 40 kW hours DC in a day (based on standard efficiency and 4 hours of good sun).

    So in theory this system should work fine.

    Now some reasons why it may not.

    Daily power consumption exceeding array output. This could be due to very high consumption (50% DOD of the batteries would be 36 kW hours for example) or less-than-ideal insolation of the panels.
    Something not working properly; one or more array(s) not contributing fully, defective charge controller, faulty wiring.

    At this point you need to examine each aspect of the system in turn and see what isn't working up to expectations. The first issue is going to be power consumption vs. power production.
    The second issue will be checking the production to see that each of the four segments are contributing to charging, and they should be fairly equal (about 50 Amps max from each controller). What is more the controllers should agree on charge stage (Bulk/Absorb/Float all at the same time) and Voltage (both battery Voltage readings and charging set points).

    A battery bank that large will need maximum charging current to reach Absorb and finish the Absorb stage before running out of sun. If the sun goes low before Absorb is done you will not see Float; the Voltage will drop to whatever level can be maintained against the loads with the available sun, which may be below the Float Voltage set point.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt pallel HELP

    All the system works perfctly. The problem are the tristar, if I set them to stay 150 minutes in absoption mode and then to pass in float it con not continue to stay in absorption apart from the percentage of the bank. Anyway I have a Victron that monitors the bank (http://www.victronenergy.com/battery-monitors/bmv-600s%20and%20bmv-602s/ ). I think that they go in conflict also if the settings are right. I have the midiac manual (absorption 57,6, float 54, equalizetion > 58 )
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP

    It's good to have manuals. I've just wasted quite a bit of time trying to get the lousy 'yahoo.net' server our host keeps manual on to release the TriStar one. :p

    The battery specs you give do not match any of the TriStar's preset selections. This is why I suggested the custom settings. Choice #5 is closest: on-off-off 14.6 13.5 15.3 28 And also set Switch 7 to off (manual equalization).

    So the problem is you never see 'Float' right? But if you take hydrometer readings you do get a specific gravity that indicates fully charged batteries at the end of Absorb?

    Are you aware that the TriStar will add 30 minutes to the Absorb time if it detects that the battery Voltage has fallen below 50 since the last charge cycle?

    Do you have the battery Voltage sense wires attached? They are not mandatory but may be a help considering the amount of current involved here.

    Your battery monitor has no bearing on the charge controllers, but the controllers will have a bearing on the monitor: it is possible for Absorb to be 'finished' long before the controllers actually exit that stage. This is why I suggested checking the current out of the controllers. If it goes down to around 2-3 percent of capacity (45 Amps or less divided by the number of controllers or 11 Amps each) Absorb is done even if the charge controllers do not recognize it.

    As a note to anyone else reading this, for a system of this size and type the TriStar is not a good controller choice. This system would be better served by MidNite Classic controllers (possibly only three) with the 'follow me' function enabled. That way there would be no discrepancy as to charge stage or Voltage and the MidNite Whizbang integrated monitor would make sure the charging ended at the right time. But I doubt the OP wants to drop $2,000+/- on new equipment at this point.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP

    By the way, for selections #4, 5, 6, and 7 the Absorb time is 180 minutes. That's 3 hours. It is unlikely you will get that much sun anywhere. This is another reason to choose the 'custom' setting.

    It's also one of the reasons I don't like these charge controllers. Their functionality is not the best for what they're meant to do. The Outback and MidNite controllers adjust Absorb time according to a timer (longer Bulk needed = longer Absorb) with minimum and maximum time limit, plus End Amps function and for the MidNite there is also the battery monitor control option.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    Ok for the settings, yes when the Victron gives SOS at 100% the density is 1.240. Is the “Battery voltage sense terminals” ,which is shows at page 6 of the manual, (http://www.morningstarcorp.com/wp-content/uploads/2014/02/TSMPPT_Truncated_GR_10pt_03.pdf ) the sensor? If that is the sensor I haven’t connected it,should I connect the positive with the negative of the battery putting on the right the positive and on the left the negative of the sensor? Where is visualized the tension on the Live Data View of the Tristar?Attachment not found.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP

    The battery sense terminals are connected to small gauge wire and go to the battery terminals. In this way the controller 'bypasses' the heavy current wires to determine what the actual battery Voltage is. The reason for this is that the output wires carrying current will show lower than actual battery Voltage at the controller due to the Voltage drop factor. This is most significant at the beginning of Absorb when you need to start the stage with an accurate Voltage reading and current will still be fairly high.

    Without the sense wires the charge controller may remain in Bulk stage longer than it needs to because the Voltage reading at the controller will be low.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    I can mark where is the positive and the negative terminal, or is indifferent as the temperature sensor
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP
    walter01 wrote: »
    I can mark where is the positive and the negative terminal, or is indifferent as the temperature sensor

    It is not a temperature sensor; it is a Voltage sensor (meter). Polarity matters.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    Yes, I understand, but could you tell me the polarity of the terminal, the positive on the right and the negative on the left, which must be connected to the positive and negative of the battery bank?
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    I'm sorry have I to connect, as in the drawing, positive on the right and negative on the left? I don’t want to reverse the polarity and cause a short circuitAttachment not found.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,500 admin
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    Re: tristar mppt parallel HELP

    Do you have a volt meter handy?

    With the main battery cables connected, you should be able to see the polarity.

    ,
    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt pallel HELP

    if I reverse the polarity of the risk of a short circuit on the tristar
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP

    I just wasted 15 minutes trying to get the diagram to load from that lousy yahoo server.

    Instead, look at this diagram from High Piggott's wind site: http://scoraigwind.co.uk/installing-and-configuring-a-tristar-controller-for-a-wind-system/ (Disregard that it is showing the controller used for diversion load.)

    Note that the positive connections are all to the left and the negative connections are all to the right.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt pallel HELP
    walter01 wrote: »
    if I reverse the polarity of the risk of a short circuit on the tristar


    Negative is "in common" with the other negatives. The short will be through the very fine sensor wire which will burn up. If you're unsure, put a 1 Amp fuse on the wire so it blows before the wire burns.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    Thank you, good idea
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    Difficult to tell the polarity of the voltage sensorAttachment not found.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP

    Check with meter. Negative will be common to the other negative terminals.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    The tester is not polarity because it is the current which is to get to the terminal
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
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    Re: tristar mppt parallel HELP
    walter01 wrote: »
    The tester is not polarity because it is the current which is to get to the terminal

    Nope.
    Connect a Voltmeter positive lead to the known positive battery terminal on the controller. Touch the meter's negative lead to one of the sensor connections. If you get zero Volts that is the positive sensor connector. If you get +48 Volts it is the negative sensor connector.

    The only bad thing you can do is connect the wire from the battery positive to the Voltage sensor negative connector; that will make a short. If you connect negative battery to positive sensor nothing will happen. And of course the only other choice is negative to negative and positive to positive, which is what you want.

    I've just been trying to find a definitive picture or diagram at Morningstar's web site. No help. Useless documentation in several languages, but very short on wiring diagrams of any value.
  • walter01
    walter01 Registered Users Posts: 22
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    Re: tristar mppt parallel HELP

    also wrong polarity should do no harm to tristar
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
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    Re: tristar mppt parallel HELP

    I'll try to take a photo of my tristar MPPT tomorrow. I run mine with a very custom set of parameters, and it will try to fool you if it enters the FLOAT CANCEL mode (triggered by low battery voltage) and sit in ABSORB for the whole day.

    And try connecting up a computer, and read the settings back from the tristar, and then print them, you can easily discover quirks in your program looking at hardcopy with the true voltage settings, vs trying to divide and multiply by 4

    Morningstar Corp. TriStar MPPT Setup Summary NiFeSetting_42cells__v12b.txt
    Printed on 1/5/2014 12:22:39 PM Mode: Solar Charge
    Setpoints (set the System Voltage with DIP switches 2 3):

    Regulation Voltage: 16.70 V (12V), 33.40 V (24V), 66.80 V (48V)
    Temperature Compensation: -0.030 V/degC 12V, -0.060 V/degC 24V, -0.121 V/degC 48v
    Max. Compensation Temp.: 80 deg C
    Min. Compensation Temp.: -40 deg C

    Absorption Time: 38:00 h:m:s
    Absorption Ext. Voltage: 12.23 V (12V), 24.46 V (24V), 48.91 V (48V)
    Absorption Ext. Time: 50:00 h:m:s
    Battery Service Reminder: disabled days

    Float Voltage: 16.15 V (12V), 32.30 V (24V), 64.60 V (48V)
    Float Timeout: 00:10:00 h:m:s
    Float Cancel Voltage: 11.72 V (12V), 23.44 V (24V), 46.89 V (48V)

    Equalize Voltage: disabled V
    HVD: 16.92 V (12V), 33.84 V (24V), 67.68 V (48V)
    HVDR: 16.75 V (12V), 33.50 V (24V), 66.99 V (48V)
    Maximum Regulation Limit: 16.81 V (12V), 33.62 V (24V), 67.24 V (48V)
    Maximum Battery Current: 0.00 A
    Array Voltage Fixed Target: disabled V
    LED G -> G/Y: 16.00 V (12V), 32.00 V (24V), 64.01 V (48V)
    LED G/Y -> Y: 15.00 V (12V), 30.00 V (24V), 60.01 V (48V)
    and so on.
    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 ,