Sunny Island/Rolls 530-S charging question

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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #62
    Re: Sunny Island/Rolls 530-S charging question

    Even though some people think I'm "100% wrong" I will suggest you ignore trying to maintain the EQ Voltage, ignore trying to keep the current below 20 Amps, and instead run an extended Absorb charge to try and get the SG up across the board. If you can get that up where it needs to be (and it stays up) on most of cells then try the EQ cycle to see if you can get a consistent SG across all cells.

    Frankly it sounds like your batteries are toast, and that is because the system is badly designed which fact is now haunting your attempts to recover.

    As always anyone is free to disagree and ignore my advice.
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  • palausystem
    palausystem Solar Expert Posts: 124 ✭✭✭
    #63
    Re: Sunny Island/Rolls 530-S charging question

    Cariboocoot -
    When you say "extended", what do you mean? I think my generator can give me roughly 60 amps into the battery. 6 hours of absorb for both strings together would be "normal".

    And you disagree with the idea that a long Hi-volts charge breaks up sulfation?

    And as far as "toast" goes, I'd like to think that if we have lost 50% of our capacity to damage, the cup is still half full....
    Off-grid 48v, 3 kw PV, Sunny Island 5048U, SunnyBoy, US Battery RE L16XC  6v, 800ah, Genset: Kohler 8.5 RES propane.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #64
    Re: Sunny Island/Rolls 530-S charging question

    Our system was 24 volt then, so I will put the 48 volt corrected values in parenthesis. Our bank is 2,400 (1,200) ah. I had been absorbing at 28.8 (57.6) volts (temp comp'd) for the first three months we owned the new batteries for two hours. As per Rolls' recommendation I moved the absorb up to 31.0 (62.0) and the minimum time to 3 hours. Our system, on an average day, charges at 200-250 (100-125) amps. This in itself was not enough to recover them.

    On every day that we had enough power (average probably every 3-5 days) I would hit manual equalize on the Classics and EQ them at 32.0 (64.0) for 3 hours. If the incoming power did not maintain the EQ I would start the generator and have it help out. This went on for a month and finally I got 1.255 SG. It was an unbelievably long drawn out process.

    I then left the absorb at 31.0 (62.0) for 3 hours and they have been fine ever since (for almost two years now). And the amount of capacity they gained when I finally got them up to 1.255 was NOTICEABLE! I initially set auto EQ in the Classics for once every 14 days. I since found out that is not necessary, and I have never done an EQ on them again since about the middle of July 2011. Every time I check them with the hydrometer the cells are so close on SG that it would be a waste to EQ them.

    They don't use hardly any water in winter. In hot weather in the summer when the batteries get up to 30C or above they will use quite a bit of water - two gallons or so in three months.

    As far as the amps, I don't think I charged them over 250 (125), but it's whatever it takes to hold the voltage where it's supposed to be. If they would've drawn more than 250 (125) for the EQ's I would've absorbed them a bit longer, then try the EQ again to see if the amps stay below C/10. When they start to "come back" and get rid of the sulfate off the plates they WILL start taking more amps because you are uncovering plate material that was rendered unusable. So you have to monitor that and if they start pulling over C/10, reduce the voltage and absorb them some more before going back to EQ.

    I can't stress enough that it is going to take a lot of time. You have to be patient and feed them what they want to keep the voltages where they should be. And monitor it. If they start getting hot or pulling more than C/10, stop. Let them cool down, check the water, then come back the next day, absorb them, and try it again. Eventually (hopefully) you'll get there.
    --
    Chris
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #65
    Re: Sunny Island/Rolls 530-S charging question

    Can't improve on Chris's post. :D

    EQ can break up "soft" sulphation but not "hard". The point is that you shouldn't do an EQ until you've gotten them as fully charged as possible. As you can see, Surrette Voltages are unusually high.

    Exactly what Chris said: feed them the current they need to maintain the Absorb Voltage set point, cancel only if the temp gets too high or the current climbs above the max level Surrette recommended. You should see an improvement in SG. If it stops improving, you're at the end. Push the Voltage up and try the EQ, but don't expect much. Since there's no way of knowing exactly how bad off the batteries are inside you can only try to improve them until they stop improving.
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  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    #66
    Re: Sunny Island/Rolls 530-S charging question
    ChrisOlson wrote: »
    Our system was 24 volt then, so I will put the 48 volt corrected values in parenthesis.
    Chris

    Hi Chris,

    Your website still seems to imply that a 24 volt system should be enough for anyone and that the hazards of running 48 volts outweigh the savings from lower current. Do you still hold that opinion for the average user? What caused you to change your mind about your own system? Did the size and capacity just grow past a threshold?

    BTW, thanks for putting all of your data up for the public!
    SMA SB 3000, old BP panels.
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  • palausystem
    palausystem Solar Expert Posts: 124 ✭✭✭
    #67
    Re: Sunny Island/Rolls 530-S charging question

    Chris -
    what type of Surrette battery was that?
    Off-grid 48v, 3 kw PV, Sunny Island 5048U, SunnyBoy, US Battery RE L16XC  6v, 800ah, Genset: Kohler 8.5 RES propane.
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  • SolaRevolution
    SolaRevolution Solar Expert Posts: 410 ✭✭
    #68
    Re: Sunny Island/Rolls 530-S charging question
    ChrisOlson wrote: »
    I then left the absorb at 31.0 (62.0) for 3 hours and they have been fine ever since (for almost two years now). And the amount of capacity they gained when I finally got them up to 1.255 was NOTICEABLE!

    Wow! That is a huge divergence from the Rolls charging instructions! Going by the instructions (for a system with a c/10 charging capability) the set points should be 57.6 (plus temp correction) and +/- 3 hrs of absorb time.

    I'm not arguing with Chris' success with his settings, I'm just shaking my head at how different they are from the manufacturer's instructions. This goes to highlight how essential it is for an end user to be a qualified technician when using Rolls Surrettes.

    I will never sell RS to a client who does not want to make a serious hobby out of their battery maintenance. I always counsel off-grid clients that the longevity of their batteries depends on close monitoring of usage and charging habits. Unfortunately many eyes tend to gloss over when looking at I-V curves, let alone taking hydrometer readings. It is particularly difficult to teach-old-dogs-new-tricks when dealing with a client who has already been living off-grid and managed to get 10 years from a set of batteries which they ignored (save for watering) and now they have a set of "high quality" expensive batteries that need more maintenance than livestock!


    -Still mad at RS!

    -Alex
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #69
    Re: Sunny Island/Rolls 530-S charging question

    inetdog - basically I wanted to go to a single inverter to improve the operating efficiency of our system. The only way to get one with enough capacity was to go to 48 volts. I do not really like 48 volt systems, nor do I like working with high voltage DC (>100V) input sources to MPPT controllers. But with high capacity systems it is, unfortunately, necessary. I treat anything over 50 VDC with the fear of god.

    palausystem - we have T12-250's. 24 of them.
    --
    Chris
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #70
    Re: Sunny Island/Rolls 530-S charging question

    and if it's 49v????????
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  • newl
    newl Solar Expert Posts: 53 ✭✭✭✭
    #71
    Re: Sunny Island/Rolls 530-S charging question
    ChrisOlson wrote: »
    I treat anything over 50 VDC with the fear of god.

    I didn't mind 48VDC when I used to work for AT&T/Michigan Bell/Ameritech/SBC (I went through all of them lol) unless it was wet (get an unpleasant tickle) or someone called in while I was across a pair (damned near knock me off the pole hahah).
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #72
    Re: Sunny Island/Rolls 530-S charging question

    The UL/NEC specs are sometimes a bit unclear about maximum ratings... For example, you may see 125/250 VAC rated fuses -- Yet the maximum voltage for AC is (depending on location) around 132 / 264 VAC == Which exceeds the ratings for many fuses (and can cause short life in ~115 VAC rated filament bulbs).

    Similar for DC stuff... 48 VDC battery banks are very common in telecom--But I had to assume that the voltages could go to ~62 or even near 72 volts at some times (and there were some European telecom systems that may have used ~72 volt nominal battery banks too).

    The UL engineers refused to tell me if I could use a "48 volt" rated part on a "48 volt" system (they have access to the proprietary sections of UL Listing Reports for manufacturers--End users do not).

    And depending on exact code/regulation, normally 60 Volts was the hard division between a "touch safe" vs the normal 120 VAC and above never ever touch electrical dividing line. And even then was 60 Volts really 60 VAC or 60 VDC (60 VAC is 85 VDC peak in the sine wave world). In the real world, frequency is an important part of how electricity behaves.

    Again--The whole question of a 48 volt battery bank vs 62 volt equalization... From what I have seen (in decades past) the NRTL inspectors just choose to close their eyes and call it a 48 volt system.

    -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 ✭✭✭
    #73
    Re: Sunny Island/Rolls 530-S charging question

    Along the lines of what Bill said (in case anyone was wondering) sometimes something rated as 'X' Volts and 'Y' Amps can take 2Y Amps but burn up if it gets 1.2X Volts and sometimes it can take 2X Volts but will pop with 1.2Y Amps. What's more, time at over Voltage/current makes a difference and so will temperature.

    But the worst part is, they won't tell you in advance! :cry:

    I vaguely remember issues with this when I worked for Emerson. Engineers ringing their hands and rending their garments while the women wept in sorrow .... :p
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #74
    Re: Sunny Island/Rolls 530-S charging question
    BB. wrote: »
    The UL engineers refused to tell me if I could use a "48 volt" rated part on a "48 volt" system (they have access to the proprietary sections of UL Listing Reports for manufacturers--End users do not).

    The people at Schneider Electric (SquareD) told me that while the QO Load Center boxes and breakers are OK for solar combiners up to 50 VDC, they are not OK on 48 volt systems (or MPPT) because the voltage can exceed the 50 volt limit for the UL Listing on the equipment.
    --
    Chris
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  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    #75
    Re: Sunny Island/Rolls 530-S charging question
    ChrisOlson wrote: »
    The people at Schneider Electric (SquareD) told me that while the QO Load Center boxes and breakers are OK for solar combiners up to 50 VDC, they are not OK on 48 volt systems (or MPPT) because the voltage can exceed the 50 volt limit for the UL Listing on the equipment.
    --
    Chris

    Which is not to say that they woud necessarily fail, just that they would get in trouble with UL for recommending a use which was outside the listing limits.
    Or they might indeed fail. The problem is that we don't know and they can't (legally) say.
    SMA SB 3000, old BP panels.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #76
    Re: Sunny Island/Rolls 530-S charging question
    inetdog wrote: »
    Which is not to say that they woud necessarily fail, just that they would get in trouble with UL for recommending a use which was outside the listing limits.
    Or they might indeed fail. The problem is that we don't know and they can't (legally) say.

    True. When I rewired my solar strings to go from 24 to 48 volt system I move the Vmp up to 92.4 volts. I'm still using a SquareD QO Load Center box for the combiner and it hasn't arc'd or failed yet. But I got a MidNite Solar combiner box ordered and on its way.
    --
    Chris
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  • palausystem
    palausystem Solar Expert Posts: 124 ✭✭✭
    #77
    Re: Sunny Island/Rolls 530-S charging question

    I only have some limited information re the weekend charge-session, because I had to leave before I could get SG's of a cooled down, floating, post-charge battery bank, but here's something:
    I "EQ'd" string 1 at 30 amp limit and could not hold it above 2.58v per cell for 10 hours.
    I EQ'd string 2 at 44 amp limit (which is supposedly the "safe max" for that battery) and was able to hold it above 2.58 for 10 hours. The SG readings on this string turned out better. So for now I'm assuming that more amps helped.

    A sample SG reading String 1: 1.220 to 1.233 after 10 hrs
    String 2: 1.220 to 1.242 after 10 hrs
    I can't say for sure that the SG's stopped rising - it seems some did and some didn't. And there was still a lot of variation between cells.

    I think next weekend I'll do them both again at the 44amp limit and stay up late to get the cooled-down readings.

    String one has a battery that is .06v less than its neighbors. This battery also has a cell that is close to 1.200 while the other two cells are at 1.230.
    Off-grid 48v, 3 kw PV, Sunny Island 5048U, SunnyBoy, US Battery RE L16XC  6v, 800ah, Genset: Kohler 8.5 RES propane.
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  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    #78
    Re: Sunny Island/Rolls 530-S charging question
    palausystem wrote: »


    String one has a battery that is .06v less than its neighbors. This battery also has a cell that is close to 1.200 while the other two cells are at 1.230.


    Differences in voltage and SG between unit batteries in a series or parallel string can be accounted for by differences in electrolyte level, charging history, age, exact construction and more.
    That sort of difference is expected and is one of the (few) reasons to do an EQ cycle.

    But when one cell of a single battery is significantly different from the others, it is more of a concern and suggests either a upcoming failure or that the battery was really heavily discharged and left for awhile or the the electrolyte level in that one cell was allowed to go too low, or some other such problem which raises concern about that battery's life expectancy, Mark that cell and keep an eye on it. Usually, once you get the system into good shape, you can choose a few cells as pilot cells to look at more frequently and just assume that the rest are in the same ballpark. That is one of the few times that looking at the voltage of the whole battery, while just checking the SG of one cell in it will be useful.

    All that being said, the difference between 1.20 and 1.23 is not yet a deal breaker, just a cause for concern.
    SMA SB 3000, old BP panels.
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #79
    Re: Sunny Island/Rolls 530-S charging question
    palausystem wrote: »
    I only have some limited information re the weekend charge-session, because I had to leave before I could get SG's of a cooled down, floating, post-charge battery bank, but here's something:
    I "EQ'd" string 1 at 30 amp limit and could not hold it above 2.58 v per cell for 10 hours.
    I EQ'd string 2 at 44 amp limit (which is currently the "safe max" for that battery) and was able to hold it above 2.58 for 10 hours. The SG readings on this string turned out better. So for now I'm assuming that more amps helped.

    A sample SG reading String 1: 1.220 to 1.233 after 10 hrs
    String 2: 1.220 to 1.242 after 10 hrs


    String one has a battery that is .06v less than its neighbors. This battery also has a cell that is close to 1.200 while the other two cells are at 1.230.
    Sounds like your on the way to recovery. That one lagging battery is a problem. I'd keep a close eye on it and see if your getting any improvement, if not, it should be replaced until you can isolate it and work on it by itself or dump it. Those I usually put in a tub of flowing water and use a power supply where I can hammer it by it's self. There is no reason to subject the whole bank to abusive EQ'ing for one battery. That cell could be bad or just more sulfated, hard to tell. Since you have a way to go, just watch it.
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  • palausystem
    palausystem Solar Expert Posts: 124 ✭✭✭
    #80
    Re: Sunny Island/Rolls 530-S charging question

    This just in from Rolls -
    I had asked "Steve" why the manual says 44amps "safe limit" maximum for their 400 Ah battery and he tells me that 60amps is OK and I tell him I'm confused. He says,
    Sorry about the typo's... I hit enter before I could go back and correct.

    I understand, but you also have to understand that that Manual is written by a person who only understand battereis and is thinking in terms of how thier chargers are charging the battereis on the factory floor.

    At Surrette we use Current driven chargers which operate in a much different way than any inverter (voltage) driven charger on the market.

    A well know industry fact is you want to have about 10-15% current capbility in order to charge your batteries efficiently. Otherwise you run into timing problems with the Absorbtion time. Nobody is going to run a generator longer then 5-6 hours ususally to charge a battery bank. This stems from Voltage driven chargers tapering current excessivly... You will notice you SI drop from 80 amps to less than 40-50 amps fairly quickly after you achieve the aborb voltage.

    I was recently brought on to Surrette to help them with these types of system issue, and eventually I'll be making some modification to the Surrette manual to reflect these "real world" situations.

    If you had an 60 amp charger on these 530's it won't cause a problem, as when the SI gets the Voltage up to the Absorb voltage current will drop off to only what the battery can accept anyway.
    Off-grid 48v, 3 kw PV, Sunny Island 5048U, SunnyBoy, US Battery RE L16XC  6v, 800ah, Genset: Kohler 8.5 RES propane.
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #81
    Re: Sunny Island/Rolls 530-S charging question
    palausystem wrote: »
    This just in from Rolls -
    I had asked "Steve" why the manual says 44amps "safe limit" maximum for their 400 Ah battery and he tells me that 60amps is OK and I tell him I'm confused. He says,
    Not surprising really, I posted several pages back that the batteries can only accept so much current, as you control the voltage, the current will take care of it's self to a point within reason. With all said, you still have to control the temperatures, if you let the temperature get away you'll warp all the plates.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #82
    Re: Sunny Island/Rolls 530-S charging question
    palausystem wrote: »
    This just in from Rolls -
    He says,

    Say what? Count me in the confused group too. I never heard such a line of BS in my whole life.
    --
    Chris
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #83
    Re: Sunny Island/Rolls 530-S charging question

    Math:

    10% of 400 Amp hours = 40 Amps
    11% of 400 Amp hours = 44 Amps
    15% of 400 Amp hours = 60 Amps

    No surprises that I see. :roll:
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    #84
    Re: Sunny Island/Rolls 530-S charging question

    most will not deplete their batteries beyond 50% dod either and a charge rate in the 10%-15% range will be far under 5hrs for the 80% or so of bulk charging. the absorb will take a few hours more and will taper in current so it's quite doable with the genny in the 5-6hr time cited worst case.

    maybe if their chargers are so radically different, then they better rethink how to charge these batteries in real world circumstances with real world charging equipment that we have. if they argue what we have to be incompatible with how they should be charged then maybe we shouldn't get them for our uses.

    chris,
    bs is meant to confuse or hide something.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #85
    Re: Sunny Island/Rolls 530-S charging question
    niel wrote: »
    maybe if their chargers are so radically different, then they better rethink how to charge these batteries in real world circumstances with real world charging equipment that we have.

    This is just common sense. Reading this coming from a "tech support person" at Surrette makes me wonder if they just hire people off the street at random, or what? I think they invent things on-the-fly myself because I have NEVER heard that their charging specs are based on some laboratory piece of equipment that doesn't really adhere to "real world".

    I'm sorry, Surrette, but I happen to use my batteries in the real world and I don't have one of these fancy lab chargers.

    I guess what I got from that was that I may as well take my Surrette battery manual out to the outhouse. Because that's the only place it's really useful.
    --
    Chris
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #86
    Re: Sunny Island/Rolls 530-S charging question

    I'd guess that 90% of the battery Chargers in the world are constant current chargers. I am sure theirs are just timed controlled, dumb as a rock. It's not surprising since most of their batteries are Traction batteries. All they are doing is the commissioning charge, they don't need anything fancy.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #87
    Re: Sunny Island/Rolls 530-S charging question
    Blackcherry04 wrote: »
    All they are doing is the commissioning charge, they don't need anything fancy.

    Of course. But now this guy is saying they based all their charging recommendations in the manual on that? It's little wonder nobody can seem to get Surrette batteries to charge properly on an off-grid installation.

    Just from here.

    In the old days Surrette used to have all sorts of technical bulletins, service bulletins, white papers and specs on different battery series tested in real world conditions on their website. Has anybody else noticed that stuff is all gone? I saved some of those bulletins and white papers when I downloaded them in the past. But for whatever reason - they pulled all that stuff off their website.
    --
    Chris
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #88
    Re: Sunny Island/Rolls 530-S charging question
    ChrisOlson wrote: »
    Of course. But now this guy is saying they based all their charging recommendations in the manual on that? It's little wonder nobody can seem to get Surrette batteries to charge properly on an off-grid installation.

    Just from here.

    In the old days Surrette used to have all sorts of technical bulletins, service bulletins, white papers and specs on different battery series tested in real world conditions on their website. Has anybody else noticed that stuff is all gone? I saved some of those bulletins and white papers when I downloaded them in the past. But for whatever reason - they pulled all that stuff off their website.
    --
    Chris
    I totally agree with you, their sure behind times. Stationary use of their batteries shouldn't be that new for them. You have posted your experience with them and your Voltages are over their recommendations. Maybe they will get into the 21st century one day, until then it's trial and error. Interstate battery has the same type instructions on their web site.
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #89
    Re: Sunny Island/Rolls 530-S charging question
    Blackcherry04 wrote: »
    Interstate battery has the same type instructions on their web site.

    Where are Interstate's instructions (link or something)? I got Interstate SRM-4D's in our RV - four of them.
    --
    Chris
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #90
    Re: Sunny Island/Rolls 530-S charging question
    ChrisOlson wrote: »
    Where are Interstate's instructions (link or something)? I got Interstate SRM-4D's in our RV - four of them.
    --
    Chris
    I challenged them on the 15.5 Volt absorb level. How do you get from 14.4 volt Bulk to 15.5 absorb ??

    Thank you for your inquiry here at the home office of Interstate Battery System of America. The absorption stage does keep the voltage set with the current tapering for the specified time (usually 2-4 hours). Our recommendation is using a higher voltage for the absorption for finishing off the charge.

    Thanks,

    Jeff Barron

    Engineering & Technical Service Specialist

    Attachment not found.




    http://www.batteries-faq.com/activekb/questions.php?questionid=1
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  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    #91
    Re: Sunny Island/Rolls 530-S charging question

    I guess I don't understand that either. At C/10 during Bulk the voltage is going to gradually climb to Absorb, and then you hold it at the Absorb voltage. Right? You can't just make that sudden jump.

    Color me confused yet again :blush:

    --
    Chris
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