Morningstar TS-45-MPPT Temp sensor oddity

Wanderman
Wanderman Solar Expert Posts: 180 ✭✭✭
in Off Grid Solar & Battery Systems #1
Hey all.

Finally have all three 2nd generation semi-flexible panels adhered to the roof. When all three fuses are in place and I am generating around 300 watts in low sun, outside temp is 72 degrees the temperature sensor on the TS-45-MPPT is showing 129 degrees!

Is this correct...sounds way off. The batteries were NOT boiling, I checked.

Batteries are in a drawer, bit the top is open to the air and well vented.

Comments?

Rich
www.thewanderman.com
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Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #2
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    Put a remote reading thermometer in the same location and see how they compare. Never hurts to check one instrument against another. Although you can end up with six different readings from five different instruments. Especially if one is an oboe.
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #3
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    OK. Checked with a non-contact thermometer. The Morningstar temp sensor is about right (attached to a neg lug on one of the two batteries)
    I had to add a bit (<1/4") of distilled water to the batteries and they were outgassing (not a boil...but bubbling away gently)

    Trojan 27TMX batteries (x2)

    Charging at 15.8 Amps and an outside Temp of 78 deg I was seeing 125 deg on the controller readout, which matched the temp at the lug.

    Both batteries were very close ~8 deg difference, in temperature.

    Is this too High? Is the resistance in the batteries too high and they are dying???

    Do I have the Morningstar set incorrectly (doubtful, since I haven't changed it since the testing R&D that worked fine for over a year)

    My new 2nd generation semi flexible panels are putting out more watts, around 510 in full sun...I was seeing 220 when testing just now...low sun, partly cloudy.

    Is this too high a temp or just normal ops?

    Is there anything I can test, that I haven't?

    Thanks!

    Rich
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  • PNjunction
    PNjunction Solar Expert Posts: 762 ✭✭✭
    #4
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    Have you checked the wiring itself for high-resistance / poor contact, elevating the temperature at the terminals?

    I find a handheld IR thermometer with laser pointer invaluable for this. With the laser point, It makes it easy to check the exterior temp of individual cells in a battery, from top to bottom, and also point along terminal lugs or down the wiring itself to look for hotspots.
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #5
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    I used a handheld. The terminals look OK.. I will clean them later on, but I'd love to know what the temps SHOULD be...before I go crazy!

    Rich
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #6
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    Also, I have three duplex cables (plus/Minus) running 1 from each panel to a separate fuse then on to the controller. They are standard glass bus fuses. Seems that they get HOT...one more than the other two (likely more power from that one) is there anything I can do to mitigate this. I am using 15 Amp fuses now..blew a 10 amp one on one of the new panels.

    Rich
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #7
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    How much current are you pushing through what size wire?
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #8
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    From each panel around 10-15 amps max through 6 gauge. duplex. Max wire run is 14 ft. (loop) I am still figuring out the max'es for these panels individually. From the controller to the battery, is 00 gauge.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #9
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    6 AWG should not be getting hot from 15 Amps. It shouldn't even notice it.
    Fuses will get hot because they are by necessity a 'current bottleneck'. By "standard glass bus fuses" you mean the little tubes rated for 32 Volts maximum?

    I think we need more detail on the panels and wiring. A single panel producing 15 Amps would be a rarity; nearly all of them are <10 Amps. If you have each panel on its own 6 AWG that would be overkill. The combined current of any three typical panels would not be a stretch for that size wire.
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #10
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    How did we get on to a discussion about the panels? Panel to controller is fine. The glass fuses do get a bit hot...not a big deal.

    The real issue is the battery getting upwards of 125 degrees. That was at ~20amp charge from the TS-45-MPPT.

    What should the charging temps be at ambient air temps of 78 deg F or so?

    Thanks,

    Rich
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #11
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    Wanderman wrote: »
    How did we get on to a discussion about the panels? Panel to controller is fine. The glass fuses do get a bit hot...not a big deal.

    The real issue is the battery getting upwards of 125 degrees. That was at ~20amp charge from the TS-45-MPPT.

    What should the charging temps be at ambient air temps of 78 deg F or so?

    Thanks,

    Rich

    You mentioned the panel wires and fuses were also getting hot.

    Frankly 129F is not unusual for a battery in an 'active' state (i.e. flowing current either in or out). The temperature should drop off as the current does, with some lag as it takes a while for the mass to cool down as well as warm up. How hot they get depends on how much current is applied for how long. So how much maximum current do you see and how long does it last?

    One of the important things to look for in any system is change. If the current or operating temperature is different than when it started out and all was working fine then something has gone wrong. If you have no info for "working fine" then you have nothing to compare it with. But you can keep an eye on it from now on and see if anything else happens (shortened charge time/load time for example).
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #12
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    OK, just pulled both batteries and cleaned everything. Some corrosion...not anything major. Took around an hour. When reassembled, battery temp according to the TS-45-MPPT sensor was at 87 deg F. I will monitor the temps today as it is pretty sunny and already 75 deg F ambient.

    Of COURSE I lost a split ring washer for one of the terminals. Murphy WAS an optimist!

    Rich
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #13
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    That is pretty darn high (125F) lead acid battery temperature.

    What was the case of the battery reading (i.e., was this a "hot lug" due to poor electrical connections or due to heating of the entire battery bank).

    If it is just a "hot lug", then cleaning/wiring with heavier cables can help (people have melted battery posts with poor electrical connections and/or too high of current).

    If the batteries themselves are this hot--Then you are hitting them with too much current (over ~13% rate of charge for 4-8 hours, or >20-25% rate of charge for shorter periods of time) during normal charging. Batteries should not heat very much when less than 80% State of Charge. When over 90% SOC, more and more of the charging current/energy is being directly converted into waste heat (and hydrogen/oxygen gas).

    Or your equalization/charge termination conditions are too high (at equalization, even a 2.5 to 5% rate of charge can overheat a battery if done for hours on end).

    I would be getting very nervous if you are >110F consistently during charging (equalization, just stop when >110F and let cool before re-starting equalization).

    If the batteries are in a box (or insulated box), you need to get some good air circulation through there... During equalization (charging >~90% SOC), some ~40% of the current is going into heating of the batteries.

    -Bill

    Also, to add, you nominal battery temperature is around 20-25C and you are running at ~52C, for every 10C above 25C, you are cutting the battery life short by a factor of 2. Running 30C higher:

    1/2 * 1/2 * 1/2 = 1/8th battery life

    Try to figure out how to get the batteries cooler (closer to room temperature)--They should last much longer.

    Plus, if you are have too high of charging voltage (too much equalization, etc.), you will also cause early battery death from positive grid corrosion (Oxygen gas forms on the positive plate during gassing and will eventually cause corrosion on/in the positive plate).

    -BB
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #14
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    OK. Sun is now mostly down and I am inot the "NIGHT" mode on the morningstar. The regular converter charger takes over at this point to keep the batteries on maintenance mode. Its a Progressive Dynamics PD4600 series with 4 stage charging. Right now it's sending 13 Amps!! to the battery.

    It seems to me, somewhere I have something going on that is making the charge controllers (Solar and Shore) believe these batteries need more amps.

    Any ideas??

    Thanks,

    Rich
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #15
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    Chargers do not send Amps to batteries: batteries draw Amps from chargers. Low SOC or internal short will draw more Amps. If you have high current demand and high temperature of a battery for a long time (ought to recharge in a day if designed correctly) I would suspect a shorted cell. Keep in mind that such can still read 'proper' Voltage as the 2V 'missing' from one cell is made up across the others, which doesn't do them any good.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #16
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    I just checked your battery specs: 105 Amp hours, 12 Volt. So in parallel that's 210 Amp hours.

    If you've got 300 Watts of solar then you could potentially put 20 Amps to them, which is fine. Even 15 Amps is good.

    How low are they being discharged? 210 Amp hours isn't much capacity (a bit more than 1 kW hour), perhaps they are being pulled below 50% SOC?

    They are also flooded cells. Your hydrometer is your best friend. Use it. Find out if they are being fully charged and more important if the cells are equal in SG.
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #17
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    The batteries are not really being used at the moment. They always have some external power source, whether it's solar (500 watts total not 300 I was just seeing around 300 this afternoon) so they haven't been drawn down at all over the past few months. Certainly not past 50%. That is why it is odd they are drawing so much current. It should simply be maintaining them. I have equalization turned off, so that's not it.

    I will check the SG's tomorrow.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #18
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    And what is the voltage/temperature of the batteries...

    If they are running at 50C on a 6 cell/12 volt battery bank

    -0.005 Volts per cell * 6 cells * (50C-25C ref) = -0.75 volts charging from "room temp set point"

    If 14.75 volts is your desired set point, then the temperature adjusted set point should be 14.00 volts. If you have hot running batteries and no remote temperature sensor (AC charger)--That could be an issue.

    -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 ✭✭✭
    #19
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    BB. wrote: »
    And what is the voltage/temperature of the batteries...

    If they are running at 50C on a 6 cell/12 volt battery bank

    -0.005 Volts per cell * 6 cells * (50C-25C ref) = -0.75 volts charging from "room temp set point"

    If 14.75 volts is your desired set point, then the temperature adjusted set point should be 14.00 volts. If you have hot running batteries and no remote temperature sensor (AC charger)--That could be an issue.

    -Bill

    Uh, Bill; look at the title of the thread.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #20
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    Wanderman wrote: »
    How did we get on to a discussion about the panels? Panel to controller is fine. The glass fuses do get a bit hot...not a big deal.

    The real issue is the battery getting upwards of 125 degrees. That was at ~20amp charge from the TS-45-MPPT.

    What should the charging temps be at ambient air temps of 78 deg F or so?

    125F ~ 52C

    I think I am on track.... But I have been wrong before (but not since yesterday :p).

    -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 ✭✭✭
    #21
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    BB. wrote: »
    125F ~ 52C

    I think I am on track.... But I have been wrong before (but not since yesterday :p).

    -bill

    Close enough for government work. :D
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #22
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    It's night now. No sun. 120V converter/charger is still charging, though it has backed down to 10 amps. Bat temp according to the morningstar sensor is 114 deg F. Will check in the AM.

    Could be the full cleaning has exposed some undercharging fault and the system is getting the batteries up to "full" charge. We'll see if it tapers in the AM.

    I have a sneaking suspicion that I will need to find 2 new batteries. I really didn't want to pay ~200 each right now, but what can I do. I will likely try and find either SCS225s or 31XHS Trojans and give my self a wee bit more power (130ah/20hr rate)

    Lithium Phosphate is still too costly for me to put in. Ah well.

    Suggestions are always welcome!

    Rich
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #23
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    Suggestion: two 6 Volt 220 Amp hour GC2's in series. Cheap (especially if you can get 'warehouse' brand), no parallel wiring worries, slightly more capacity than the 210 you've got now.
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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #24
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    I looked at 6 Volt batteries, but ike the redundant 12v sources. In the middle of no where if one dies...I still have 12V.

    Also the size of the battery "drawer" limits me significantly.

    It's 14" x 18" x 10" maybe a little bit less. Maximizing the amps is paramount. Though max used EVER was 80aH overnight. Usually I am at 45aH or so.

    Rich
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  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    #25
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    Wanderman wrote: »
    I looked at 6 Volt batteries, but ike the redundant 12v sources. In the middle of no where if one dies...I still have 12V.

    Same odds, you have 2 batteries. What changes is that batteries in parallel are more likely to fail early, then series batteries. All depends on the wireing scheme, if it allows the batteries to share power at the uOhm level
    Also the size of the battery "drawer" limits me significantly....
    gotta do what you gotta do.
    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 ,

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  • Wanderman
    Wanderman Solar Expert Posts: 180 ✭✭✭
    #26
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    OK...one of the batteries is toast. Almost literally. The odd burgundy case is now a few shades darker from the heat. It's now removed. I have rewired so the other battery is now the ONLY battery. It immediately went down to around 3 amps maintenance charge on the sensors and it appears the heat is slowly going down. I will check again later tonight.

    So, essentially, both batteries need to be replaced. I am going to look for TROJAN 12 VOLT FLA SCS225 or 31XHS (some variant with a top screw terminal. A bit more power, not much extra cost and they will fit the 14"x18"x10" space. Any idea if one is better than the other?

    Anyone know where to get these at a reasonable price in or around NY ( 12428 ) so I can pickup and avoid shipping heavy lead around???

    I would LOVE a set of blems as they can be 1/2 the cost.

    I'm toying with the idea of replacing the engine start battery, which can be connected to the main house system with a switch (not a battery isolator) since it's probably OK for that use. Maybe.

    Rich
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #27
    Re: Morningstar TS-45-MPPT Temp sensor oddity

    I am glad you found the bad battery... There are a fair number of fires started by battery systems that draw too much current during charging/floating (shorted cells, wrong set points, bad charge controllers, etc.), "boil" the water away, and then light off (or explode if there is still hydrogen gas around in the cells/area).

    Just an overall warning--When something does not look "right"--Do more investigation/research until you find the answer(s). Otherwise, something can go terribly wrong later.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • scrubjaysnest
    scrubjaysnest Solar Expert Posts: 175 ✭✭✭
    #28
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    Cariboocoot wrote: »
    Suggestion: two 6 Volt 220 Amp hour GC2's in series. Cheap (especially if you can get 'warehouse' brand), no parallel wiring worries, slightly more capacity than the 210 you've got now.
    and to heavy to lift if your an old man like me.
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  • scrubjaysnest
    scrubjaysnest Solar Expert Posts: 175 ✭✭✭
    #29
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    mike95490 wrote: »
    Same odds, you have 2 batteries. What changes is that batteries in parallel are more likely to fail early, then series batteries. All depends on the wireing scheme, if it allows the batteries to share power at the uOhm level

    gotta do what you gotta do.
    My personnel experience is stay with the two 12 volt; lose a cell on a 6 volt your dead in the water in the boonies and many times a replacement is difficult to get besides becoming a 3 to 5 day turn around time. Saw this in Blowing Rock NC. Also the 6 volt can be difficult to lift into place in some RV's. The 12 volt will have slightly lower aH's; mine are 210 vs 225 for a pair T 105's and more common for replacement. I get 5 years typically from 2 12 volt in parallel. For an off grid cabin the 6 volt are fine. Just not my first choice for an RV.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #30
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    scrubjaysnest wrote: »
    and to heavy to lift if your an old man like me.

    I am an old man and they're not too heavy to lift.
    The 6 Volt 220 Amp hour package weighs about the same as a 12 Volt 110 Amp hour package: the weight issue is moot.

    The matter of one battery failing when you're away so you still have one to work with might be valid, though. Strangely I've seen more 12 Volts fail than 6 Volts. Makes me wonder just how robust the 12 Volt deep cycles really are. Perhaps manufacturers take a bit more care about such things when they're building batteries meant to be jostled about in golf carts.
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  • scrubjaysnest
    scrubjaysnest Solar Expert Posts: 175 ✭✭✭
    #31
    Re: Morningstar TS-45-MPPT Temp sensor oddity
    Cariboocoot wrote: »
    I am an old man and they're not too heavy to lift.
    The 6 Volt 220 Amp hour package weighs about the same as a 12 Volt 110 Amp hour package: the weight issue is moot.

    The matter of one battery failing when you're away so you still have one to work with might be valid, though. Strangely I've seen more 12 Volts fail than 6 Volts. Makes me wonder just how robust the 12 Volt deep cycles really are. Perhaps manufacturers take a bit more care about such things when they're building batteries meant to be jostled about in golf carts.
    How robust they are could be a good point as there is plenty of jostling on the roads we travel.
    As for the weight issue I weighed mine yesterday and they were 63.8# each vs a T 105 at about 65#. So the Exides didn't gain me anything there beyond two cans of beans that would have to be left out with the Trojans. Weight in an RV is a major balancing act. They do have a nice built in handle which helps.
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