Rolls Support or lack of it

Ako
Ako Registered Users Posts: 184 ✭✭
Contacted Rolls in the hope i would get a response with more information than i had before which was not worth the effort . After filling in all the details of my batteries and system which i assumed would be to assist them in their diagnosis and advice i wrote a rather long description of the problem trying to include anything i thought would be relevant , maybe i was expecting to much from after sales ................

I contacted Rolls some months ago as I had become concerned at the high Sgs my batteries and voltages were now showing . Rolls advice was to reduce the voltage 0.04 to 0.06 and the absorption time which I did , the reduction in voltage , and filling the fluid to the upper level worked to a limited extent and the Sgs dropped to 1.260 - 1.265 at 35c , they have now started creeping back up to 1.270 - 1.275 at 35c . The batteries receive a full charge each 24 hour cycle .The batteries are 18 months old and replaced Trojan batteries of the same specs which lasted 10 years . I am maticulose in ensuring all instructions are followed and for a year everything was fine and the batteries were showing all readings as they should , the Sgs were within 0.1 - 0.2 and voltage for each battery within 0.1v , all when fully charged and early morning prior to charging , they still are , then for no apparent reason the Sgs started to rise to around 1.30-1.31 . The manual says a charging voltage of 30v however a few weeks after installing friends informed me it should be 29.76 so I contacted Rolls to ask and they came back with the same Voltage 29.76 .I can see a medium to dark gray crystal like deposit the same colour as the plates on the top of every other plate in every cell . All cells act in the same manor , and apear identical , very little water use and all bubbling equally for several hours a day . My consumption is around 4000 watts split evenly between the charging periods and night time use although . I have positively ruled our problems with charge controller , hydrometer and RTS , they are all accurate and functioning correctly . The batteries came charged and I would never add acid , only distiled water the same one I and friends have been using for 12 years so I doubt thats an issue . I live in Spain and the weather is reasonably constant for 6 months of the year .

Im sure there are other facts you might require to assist in identifying the problem and suggesting a solution and I would be happy to supply anything necessary .

Their reply...............

1.265 to 1.275 is where you want to have them when they are fully charged... 

If you want to lower them you can lower your absorb voltage or absorb time. 

Battery spgs are going to fluctuate depending on how much solar you get, or load you use. 

Regards,

My response.................

Thank you for the speed of your response but sadly it only demonstrated that you don't feel my concerns deserves anything more than a quick piece of advice that you could have seen i already knew , telling me what the SG readings should be when my reason for contact was because they are higher than that i knew they should be was pointless . After the time and effort i went to i was hoping you would at least explain what the grey deposit were after i went to the trouble of photographing is and if its doing damage and also give me a possible explanation as to why SGs rise for no apparent reason in batteries that had been in service and performing perfectly for a year without any change of circumstances .

I also dont understand why your manuals etc give Absorption voltages and you later advise to use lower ones , either the ones given in your literature are right or there not , how often would you advise customers to use lower ones .

Of course battery SGs are going to fluctuate depending on charge going in and load but my communication showed neither can be a factor as batteries have sufficient charge in a 24 hour cycle and SG readings are not taken at random times while charging or discharging , they are taken just prior to the commencement of charging ( their max DOD ) and after they have been in float for at least an hour with only a nominal current going in ( MAX charge possible not counting Equalization ), voltages taken after charging finishes and at rest for an hour but still showing 25.6v .

Frankly your reply was a total waste of your time as was my own initial inquiry  .

 

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Comments

  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    edited August 2018 #2

    Hi Ako,

    When you say,  "   ,,,   the Sgs were within 0.1 - 0.2 and voltage for each battery within 0.1v    ...   ",   What  is the range of SGs are you referring to ?

    The photos do not seem to show anything in the vent well,  other than a reflection of the flash,   do not know what are the vertical striations in the images,   but,  perhaps it is on the "lens" (?).

    It is normal for some eroded plate debris to be deposited on the tops of the Moss Guard,  separators  or plates.   Am not sure that the 4000 series of Surrettes  still use a Moss Guard ...

    Some of us have suggested getting one,  or,  even several new Hydrometers,   as a reality comparison to the existing "expensive" ones that you have been using.

    Also,  will again mention,  that Hydrometers need to be RINSED,   RINSES,   and RINSED yet again,  with Distilled Water after each measuring session.   Personally would not leave a Hydro un-rinsed for more than an hour,  even if you will use it again in an hour or so ...

    AND,  it was also mentioned to study and follow the Surrette Article,   "Measuring Specific Gravities",  under the Support Tab on their site.

    I have found Surrette Support to be very good,   FWIW.

    Just a drive-by,   back to work here,   good luck,   Vic

    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Ako
    Ako Registered Users Posts: 184 ✭✭
    edited August 2018 #3
    The SG and individual battery voltages always have been fairly close irrespective of the range of SOC or DOD  , even when the SGs went silly , the difference between the cells for voltage and SGs remain close , so either they are all good or all bad . For a year 1.255- 1.270 with fully charged batteries or 1.200 - 1.220  early mornings then when the SGs went up this last few months 1.29 - 1.31 when fully charged . while early morning when i have max DOD the readings are also in the same margins although at a higher range 1.220 - 1.230 .

    I have read the Surretts article some time ago and , what ever is suggested by you and others who obviously have a lot more knowledge and experience than i do i have done , would be pointless if i asked for advice then didnt act on it and it all made perfect sense to me anyway once i thought about it .

    Sorry i cant agree about Rolls support , i get the impression from what they wrote today that like a lot of company's they quickly skim through inquiries without bothering to digest whats said and do a quick response to whatever bits register and is simple to reply to . They don't seem to be as interested in helping than in processing the workload . Possibly some are better at their jobs than others and i just got the wrong one .At least Rolls didn't do what a lot of UK banks do , they just choose from a set of a pre written response selecting the one they think is closest although they often have absolutely nothing to do with the inquiries  . 
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  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭

    OK,  and on an or some additional Hydrometers,   whatta you think?

    Am in transit,   later,   Vic

    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Ako
    Ako Registered Users Posts: 184 ✭✭
    I do plan to buy a new one , i really dont think mine are a factor but you know yourself the cost of a decent solar system , a new hydrometer is a drop in the ocean and worth every centimo if it helps . Im going to get a temperature compensated one this time so i dont need to keep having to add the temperature factor .
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  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    Didn't you go through all of this in a previous topic?

    A wild guess - your distilled water wasn't as pure as you think.

    I am available for custom hardware/firmware development

  • Ako
    Ako Registered Users Posts: 184 ✭✭
    edited August 2018 #7
    Yes i did, it was the response from Rolls today that so infuriated me that i posted on , Vic picked up more on the content of my contact with Rolls and offered some useful advice which is more than Rolls did .

    Nope nothing wrong with my distilled water , were all still using the same one , no choice really theres only one supermarket in the area that has ever stocked it .
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  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    It seems to me either the high SG readings were wrong, or something made the acid more dense. That something could be distillation (ie water loss), stronger acid in the initial fill, or adulteration in water added.

    In most of these cases though, it seems to me the solution is the same.

    If the SG read is high, but consistent, that's your baseline. You've added water to full, so that rules out distillation. There's no way to test initial fill acid strength now, but if it was stronger, I'd rather have the extra in the acid rather than hardening on my plates. I'm not sure what could adulterate the water enough to make it denser than battery acid, but it would probably be nasty and not play well with clothes irons and other stuff that you'd use distilled water for. You could rule that out, at least with your current supply by weighing it.

    Unless the distilled water is bad (in which case I suppose you could redistill it), IMHO the solution is to just accept that 1.31 or whatever is normal (as measured) for your batteries.

    I haven't seen it, but I suppose it's possible bits of sloughed off lead could contaminate the SG sample enough to cause a high reading, but it seems pretty unlikely that would be consistent and repeatable.

    FWIW, I think the Rolls advice to lower the SG by deliberately undercharging is wrong. Sure, it lowers SG, but that just sulfates and lowers battery capacity.
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  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    Steve Higgins at Rolls is excellent. If he told you what to do, you can't get any better advice than from him!
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  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    No experience dealing with Rolls specifically, but as a general proposition, getting to the right person is key to getting good advice. Getting there can be hard though.
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  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    The only way the solution could become more dense would be the addition of acid, or another soluble substance, ruling out this would leave lower water than what is required to achieve the target SG. As I've pointed out in the other rather long post , I too have seen my SG higher than what they were when first purchased, in the cooler months,  during the hot months is when this phenomenon occurs. As the battery temperatures are generally in the 30-36°C my assumption is due to expansion, the electrolyte level has risen so the new fill level should actually be higher than the level stated in the specs, which would use a base temperature, probably in the 25°C range. Adding water to a higher level brings  the SG back to more normal levels but it creeps back up as water is lost, personally I choose to ignore these fluctuations because my understanding or assumptions, as described above, satisfies my curiosity. 
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  • Ako
    Ako Registered Users Posts: 184 ✭✭
    At least its good to know someone experienced has also seen SGs rise for no apparent reason and knowing as i do there was never acid added or anything other then distilled water . Your experience described above mirrors my own . I agree with Estragon that the advice to undercharge just to keep SGs normal isnt the correct way to go because it will only lead to unnecessary sulfates  which would also be Rolls way out when they fail .

    Rolls just wont answer why the problem occurs , they must know after so many years in business , they will also have had a lot of others asking why . Their answer is always along the lines of " 1.265 to 1.275 is where you want to have them when they are fully charged... 
    If you want to lower them you can lower voltage or absorb time. 

    Their right , it works but not really the answer , so now its a question of which is worse for the batteries , undercharging for months or High SGs . Your choice to leave SGs high must mean you considered both and went for High SGs as the lesser of two evils  .







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  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Basically I think it's a high temperature issue, I have no technical support by the way, I've left the settings alone letting the RTS to compensate for voltage. Bulk 30V, 1 hour into absorbtion, dropping to 29.6V for the remainder of the 180 minutes total, or 2% battery capacity which ever occurs first, on cloudy days absorption is extended to 6 hours, SG 1.285 to 1.300 depending upon electrolyte level, it is what it is, not much need for equalization. Inside the cells there is no fluff, plates are clear as the day they were purchased 18 months ago, or 540 cycles, how many more?  That's an unknown, hopefully 540 more.

    The reduction of voltage to reduce SG is, in my opinion, a pasificication response, telling you what you want to hear, sure it may work at the expense of capacity, ignore this and wait until temperatures drop to  "normal  25°C " is my suggestion, for what it's worth. 


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    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
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  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    Assuming the SG actually is high (not an artifact of miscalibrated or otherwise misleading read), it's worth noting that batteries are sometimes filled with more concentrated acid deliberately to increase capacity.
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  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Estragon said:
    Assuming the SG actually is high (not an artifact of miscalibrated or otherwise misleading read), it's worth noting that batteries are sometimes filled with more concentrated acid deliberately to increase capacity.
    Interesting,  but at the beginning of this venture, everything was normal, something changed, ambient temperatures seem to be the wild card.
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    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
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  • Ako
    Ako Registered Users Posts: 184 ✭✭
    edited August 2018 #16
    Same for me , nothing changed other than aprox 10c temperature increase to around 35c , RTS working as it should , compared temperature with a thermometer and they matched . 

    Having said that , fitted batteries new Jan 2017 so went through last summer with same weather and temperatures and didnt show any SGs outside the normal range than they did in Jan to May when it was much colder .
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  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    Since your SG readings are suspect,  measure fully charged idle voltage and if correct (ie, not too high), don't worry about high SG readings - they don't accurately reflect your acid concentration.

    I am available for custom hardware/firmware development

  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    > @mcgivor said:
    > Estragon said:
    >
    >
    > Assuming the SG actually is high (not an artifact of miscalibrated or otherwise misleading read), it's worth noting that batteries are sometimes filled with more concentrated acid deliberately to increase capacity.
    >
    >
    >
    >
    > Interesting,  but at the beginning of this venture, everything was normal, something changed, ambient temperatures seem to be the wild card.

    Yah, my guess is also that the reading is misleading through temp effects or otherwise. The comment about stonger acid was mainly to note that higher SGs are SOP in some applications, and within reason, not something to get too worried about (vs chronic undercharging, which I would worry about).
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  • Ako
    Ako Registered Users Posts: 184 ✭✭
    edited August 2018 #19
    I did that and reported t to Rolls when the SGs went to 1.30 - 1.31 , the voltages were around 25.8 and took quite a while to drop to anywhere near 25. , in fact i was having around 24.8 to 25v early morning when for the previous 12 months i had become used to see 24.2 - 24.5.

    Reguarding the voltage Rolls said......A fully charged and resting battery is going to measure 2.13vpc or 25.56 volts

    Re guarding the SGs Rolls said ......" I would be worried if the Spg's were much higher at least above the 1.280 to 1.290 range "

    Had a thought , doubt its a factor but i noticed when the filing caps are taken off they are grey and sticky can scrape it with finger nail so its built up , might be blocking air passage or dripping into the cells as batteries bubble constantly for hours after they reach a certain voltage . Any suggestions what to use to neutralise's and clean them , my concern is that residue from baking soda , white vinigar or ague fuerte could find its way back into the fluid .


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  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    > i had become used to see 24.2 - 24.5
    Then you were seriously under-charging before - not normal.  

    While 25.8V is close, you could dilute your acid slightly to get the proper 25.56V fully charged/resting/temp compensated voltage value.

    I am available for custom hardware/firmware development

  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    Baking soda & water, and no, you don't want to get it in the cells. Rinse thoroughly after in plain water and dry before replacing should work.
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  • Ako
    Ako Registered Users Posts: 184 ✭✭
    edited August 2018 #22
    jonr said:
    > i had become used to see 24.2 - 24.5
    Then you were seriously under-charging before - not normal.  

    While 25.8V is close, you could dilute your acid slightly to get the proper 25.56V fully charged/resting/temp compensated voltage value.
    That was around 7.30am Jonr after i had been consuming about 100 amp/hrs during the previouse 12 hours with no input , end of charge voltages the day before were around 25.6 . All seemed to be about right to me . Didnt thing temperature was a factor thought only while charging voltages had to be adjusted for temp .

    Thanks Estragon , baking soda water a good rinse and dry  it is then 
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  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    Temp effect is very small, but might as well do it.  More info here:
    http://www.scorekeeper.com/jaguar/BatteryChargeEstimates.pdf

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  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    are you re-calibrating your hydrometer for the difference in temperatures ?  They come with a correction chart
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  • Ako
    Ako Registered Users Posts: 184 ✭✭
    edited August 2018 #25
    Thanks Jonr , i read it right through and as you say the temperature effect on resting open circuit batteries is small although it works in my favor as would reduce the voltage im seeing once the temperature compensated factor was taken off  but at 25c by only 3 decimal places , unfortunately my multi meter and MSView only go to 2 decimal places . Was also interesting to see how they came to a figure to estimate the SOC or condition of a battery from its voltage .

    There good ones Mike but not temperature compensated so i add 0.006 for every 5c above 25c  , basically adding 0.012 each day as im 35c almost every day . 1.280 becomes 1.292 etc .


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  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    According to Rolls, if I'm reading this right, the adjustment would be .0054 at 35C so 1.28 is ~1.285?

    http://support.rollsbattery.com/support/solutions/articles/208145-specific-gravity-temperature-correction-factors
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  • Ako
    Ako Registered Users Posts: 184 ✭✭
    Your right  Estragon , Rolls round it off by saying add  0.003 for every 5c , today i doubled that to 0.006 because im double the 5c then today when i gave an example for some inexplicable reason i doubled it again because my system is 24v , of course i realize its SGs not voltages , call it a senior moment .  When i take SGs though at this time of year i just mentally add half a point for simplicity as i have been more concerned at the 0.30 to .0.40 readings , half a point i could have lived with . 

    Just had a third day when things seem to make more sense . Three days ago i lowered voltage 0.3v and added a bit more water , not much but my readings last 3 days have been identical  on each cell at 1.24 - 1.25 , adjusted thats 1.245 - 1.255  so their lower than i was hoping to achieve and i think thats due to the lower voltage , the voltage also drops of a bit quicker during the evening than when the readings were normal,although im getting the same number of amps going in during the day . I dont think the lower voltage set points were necessary,  i think the addition of water was the main factor . Im going to bump up the voltage to what it should be 29.76 and im fairly confident my SGs will be where they should be , im sure its the water thats made the difference as it did before when they stayed around where they should be for 2 weeks before starting to creep back up . If im right then these batteries are very sensitive to filling levels , also seems i will need to top them up every couple of weeks if not weekly . When its cooler im hoping not so often . Hopefully others experiencing the same phenomenon can try what i have to confirm im right . Assuming i am of course .
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  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,728 ✭✭✭✭✭✭
    I think you are overthinking all of this. Just an opinion....
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  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    Batteries empowered with higher SG are sometimes marketed as high performance batteries and sold at higher prices. Considering the consequent lower lifespan, I consider this practice unethical in absence of advisement about the shorter lifespan.

    I wonder if removing electrolyte and replacing with distilled water would add to life. I suspect the answer may be yes. How about draining all of the electrolyte for storage purposes? We used to be able to buy dry batteries that we added electrolyte to when putting into service. I think some came with dry/powdered electrolyte. Perhaps they had to dumb things down?

    Estragon said:
    Assuming the SG actually is high (not an artifact of miscalibrated or otherwise misleading read), it's worth noting that batteries are sometimes filled with more concentrated acid deliberately to increase capacity.
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • Tecnodave
    Tecnodave Registered Users Posts: 437 ✭✭✭✭

    Manufacturers of batteries used in artic conditions use a higher percentage of lead to electrolyte and a much higher s.g. than normal uses. I worked for Alaska Husky Battery in Fairbanks, Alaska and our winter battery for the -70 degree Fairbanks winters used 1.320 as the "full charge" s.g. These batteries would not survive Fairbanks under hood summer temperatures. Fairbanks,Alaska record high temp 109 degrees......Buyers were advised to use them in the winter and store them in summer. They did not freeze at 70-80 degrees below zero Fahrenheit . Covertly tropics batteries have a much lower s.g. to tolerate tropics heat.

    I have a U.S. Navy WW-II hydrometer which has four floats, artic, normal, tropic,and temperature for correction.

    Alaska Husky Battery still exists...U.S. EPA ran them out of business.....to Moscow,Russia where they produce batteries for the Russian Military

    David

    2 Classic 150, 2 Kid, 5 arrays 7.5 kw total  2ea.  2S6P Sharp NE-170/NE-165, 1ea. 12P Sanyo HIT 200,  2ea. 4/6P Sanyo HIT 200, MagnaSine MS4024AE, Exeltech XP-1100,  2 Banks L-16 battery, Rolls-Surette S-530 and Interstate Traction, Shunts with whizbangJr and Bogart Tri-Metric, iCharger i208B  dc-dc buck/boost converter with BMS for small form lithium 8S 16650 or LiFePO4,