Page 2 of 3 FirstFirst 1 2 3 LastLast
Results 21 to 40 of 42
  1. #21
    Join Date
    May 2009
    Location
    Hillcrest
    Age
    67
    Posts
    24,599
    Thanked: 20832

    Default Re: Testing battery capacity

    Quote Originally Posted by the_terrible_triplett View Post
    For wot, R2k, you can have Bluetooth acces, App on your phone and data for the life of the battery.
    https://www.sunstore.co.za/products/...-battery-shunt

    Know your battery usage. Measure it.

    Just saying.
    But but but, it's Blue.

    Totally agree with, a truly excellent product for a home solar system.

    However, for camper trying to keep track of his dual battery system - naw completely OTT.

    You really don't need to have to attach a Bluetooth Cellphone while making breakfast on the skottle to find out if the battery is 45 or 47%

    You want to peer over the edge of your beer at the battery system and determine if you are good to go or not.
    Cheers

    NAGOF

    HAM Callsign - ZS5KAD

    Freedom of speech is useless unless you allow people you don’t like to say things you don’t like………

    If you fly or drive to an anti-Fracking meeting, you have no business being there and you wont get my ear......

  2. The Following 3 Users Say Thank You to Fluffy For This Useful Post:


  3. #22
    Join Date
    Aug 2013
    Location
    Pretoria
    Age
    39
    Posts
    427
    Thanked: 241

    Default Re: Testing battery capacity

    Agree, these devices are cool and all but I do like to keep it simple when out camping. Phone packed away type of camping.

    That is why I want to do at home tests, so I know how long I can go without a charge...
    2014 Hilux D4D dc 4x4
    2013 Metalian Maxi

  4. #23
    Join Date
    Nov 2015
    Location
    Cape Town
    Posts
    2,804
    Thanked: 2914

    Default Re: Testing battery capacity

    Very valid points. And I have to agree with the phone off when camping. Very good point that.

    Personally, camping system, I will look for and get a BMV 700/712 2nd hand as it has a display.

    But take note when I say ... 2nd hand.

    Political Correctness
    Political Correctness is a doctrine, fostered by a delusional illogical minority, rabidly promoted by a unscrupulous mainstream media which holds forth the proposition that it is entirely possible to pick up a turd ... by the clean end!

    Saw this in a pub - no idea why the wife does not see it so:
    I'm not opinionated ... I'm just always right!

  5. #24
    Join Date
    May 2009
    Location
    Hillcrest
    Age
    67
    Posts
    24,599
    Thanked: 20832

    Default Re: Testing battery capacity

    Quote Originally Posted by the_terrible_triplett View Post
    Very valid points. And I have to agree with the phone off when camping. Very good point that.

    Personally, camping system, I will look for and get a BMV 700/712 2nd hand as it has a display.

    But take note when I say ... 2nd hand.

    As does the one in Post #18
    Cheers

    NAGOF

    HAM Callsign - ZS5KAD

    Freedom of speech is useless unless you allow people you don’t like to say things you don’t like………

    If you fly or drive to an anti-Fracking meeting, you have no business being there and you wont get my ear......

  6. #25
    Join Date
    Nov 2015
    Location
    Cape Town
    Posts
    2,804
    Thanked: 2914

    Default Re: Testing battery capacity

    Quote Originally Posted by Fluffy View Post
    As does the one in Post #18
    Yes, only difference being the BMV will store data ... if that is a need one may have, to see what is going on, identify patterns, see how the batt ages.
    Political Correctness
    Political Correctness is a doctrine, fostered by a delusional illogical minority, rabidly promoted by a unscrupulous mainstream media which holds forth the proposition that it is entirely possible to pick up a turd ... by the clean end!

    Saw this in a pub - no idea why the wife does not see it so:
    I'm not opinionated ... I'm just always right!

  7. #26
    Join Date
    May 2009
    Location
    Hillcrest
    Age
    67
    Posts
    24,599
    Thanked: 20832

    Default Re: Testing battery capacity

    Quote Originally Posted by the_terrible_triplett View Post
    Yes, only difference being the BMV will store data ... if that is a need one may have, to see what is going on, identify patterns, see how the batt ages.
    Nope, there a LOT more very important advantages over the BMV.
    Cheers

    NAGOF

    HAM Callsign - ZS5KAD

    Freedom of speech is useless unless you allow people you don’t like to say things you don’t like………

    If you fly or drive to an anti-Fracking meeting, you have no business being there and you wont get my ear......

  8. #27
    Join Date
    Nov 2020
    Location
    Cape Town
    Age
    69
    Posts
    972
    Thanked: 651

    Default Re: Testing battery capacity

    Those 100Amp "Coulometers" also now stocked by GeeWizz: https://www.geewiz.co.za/batteries/1...ith-shunt.html

    and sold via Makro: https://www.makro.co.za/electronics-...RoCR-UQAvD_BwE

    There are similar looking ones on Takealot with a 50Amp shunt: https://www.takealot.com/12v-50a-bat...E&gclsrc=aw.ds

    My 100 Amp versions have handled 150 Amp for very short periods. On the other end of the scale, if the current is much lower than the shunt rating, the reading is not accurate. In other words, no need to oversize the shunt for "just in case".

  9. The Following 5 Users Say Thank You to Jonatan For This Useful Post:


  10. #28
    Join Date
    Apr 2016
    Location
    Cape Town
    Age
    73
    Posts
    1,203
    Thanked: 255

    Default Re: Testing battery capacity

    Quote Originally Posted by the_terrible_triplett View Post
    For wot, R2k, you can have Bluetooth acces, App on your phone and data for the life of the battery.
    https://www.sunstore.co.za/products/...-battery-shunt

    Know your battery usage. Measure it.

    Just saying.
    Amazing how affordable these devices are that don't have a display..
    As good as the big brother BMV!

  11. The Following User Says Thank You to Richard Mackay For This Useful Post:


  12. #29
    Join Date
    May 2010
    Location
    Middelburg EC
    Posts
    9
    Thanked: 3

    Default Re: Testing battery capacity

    Im Trying to test my 105Ah deep cycle battery so I connected a 40watt bulb to the battery. After 8.5hrs the voltage went below 12v. Is the battery still fine?

  13. #30
    Join Date
    Nov 2020
    Location
    Cape Town
    Age
    69
    Posts
    972
    Thanked: 651

    Default Re: Testing battery capacity

    Quote Originally Posted by cliftf View Post
    Im Trying to test my 105Ah deep cycle battery so I connected a 40watt bulb to the battery. After 8.5hrs the voltage went below 12v. Is the battery still fine?
    If it started fully charged it should have done much better than that. (That bulb drew 3.5 amps for 8.5 hours = 30 Amphours. Such a test will never show 105Ah, but it should happily reach 50Ah)
    Last edited by Jonatan; 2024/05/18 at 04:18 PM.

  14. The Following User Says Thank You to Jonatan For This Useful Post:


  15. #31
    Join Date
    May 2009
    Location
    Hillcrest
    Age
    67
    Posts
    24,599
    Thanked: 20832

    Default Re: Testing battery capacity

    Quote Originally Posted by cliftf View Post
    Im Trying to test my 105Ah deep cycle battery so I connected a 40watt bulb to the battery. After 8.5hrs the voltage went below 12v. Is the battery still fine?
    Is the 12V measured with the bulb ON or OFF.

    Loaded voltage can be Significantly lower than no load voltage and is a very poor if not useless indication of battery SOC.
    Cheers

    NAGOF

    HAM Callsign - ZS5KAD

    Freedom of speech is useless unless you allow people you don’t like to say things you don’t like………

    If you fly or drive to an anti-Fracking meeting, you have no business being there and you wont get my ear......

  16. #32
    Join Date
    Nov 2020
    Location
    Cape Town
    Age
    69
    Posts
    972
    Thanked: 651

    Default Re: Testing battery capacity

    Quote Originally Posted by Fluffy View Post
    Is the 12V measured with the bulb ON or OFF.

    Loaded voltage can be Significantly lower than no load voltage and is a very poor if not useless indication of battery SOC.
    That battery was only lightly loaded at 3.5 A, and I don't expect a significant voltage difference for no load. Guessing about 0.3V immediately on disconnection, and about 0.5V after a rest period. Havn't done this for 2 years now, and my memory cells are faded.

  17. #33
    Join Date
    May 2010
    Location
    Middelburg EC
    Posts
    9
    Thanked: 3

    Default Re: Testing battery capacity

    Quote Originally Posted by Fluffy View Post
    Is the 12V measured with the bulb ON or OFF.

    Loaded voltage can be Significantly lower than no load voltage and is a very poor if not useless indication of battery SOC.
    It was 11.95 when I disconnected, and immediately went to 12.2. When I checked a few hours later it was 12.6v

  18. #34
    Join Date
    Sep 2006
    Location
    Plett
    Age
    57
    Posts
    5,272
    Thanked: 4580

    Default Re: Testing battery capacity

    Quote Originally Posted by Fluffy View Post
    Is the 12V measured with the bulb ON or OFF.

    Loaded voltage can be Significantly lower than no load voltage and is a very poor if not useless indication of battery SOC.
    Why would he test with the bulb off Or am I missing something?
    2022 Defender D300HSE
    2022 Isuzu Mux 4x2 LSE
    2019 FJ Cruiser
    BL Kewer 3188
    Fusion 17

  19. #35
    Join Date
    Oct 2009
    Location
    Kempton Park
    Age
    41
    Posts
    2,718
    Thanked: 5210

    Default Re: Testing battery capacity

    Quote Originally Posted by BruceHun View Post
    Why would he test with the bulb off Or am I missing something?
    You test with the bulb on and switch it off then let it rest before taking the reading. A battery under load wont show you the correct capacity. Although some appliances like fridges might draw the volts down to below the cut off at startup and switch off. So even with enough capacity the startup current will make it switch off again.
    Last edited by LandyLove; 2024/05/18 at 08:27 PM.

  20. The Following User Says Thank You to LandyLove For This Useful Post:


  21. #36
    Join Date
    Nov 2020
    Location
    Cape Town
    Age
    69
    Posts
    972
    Thanked: 651

    Default Re: Testing battery capacity

    Quote Originally Posted by cliftf View Post
    . . . . . Is the battery still fine?
    Depends on what the results of a similar test were when the battery was new, how old it is, what it was used for till now, what you want to do with it in future, if there is no weepage, or bulging, etc, etc

    Lots of factors before someone can assure you it is "fine"

  22. The Following User Says Thank You to Jonatan For This Useful Post:


  23. #37
    Join Date
    May 2009
    Location
    Hillcrest
    Age
    67
    Posts
    24,599
    Thanked: 20832

    Default Re: Testing battery capacity

    Quote Originally Posted by BruceHun View Post
    Why would he test with the bulb off Or am I missing something?
    Because testing with the bulb on is meaningless without some serious mathematical computations using data which is only available on the manufacturers data sheets. Not to forget the bulbs actual power draw across the actual terminal voltage.
    It involves serios computations using differential calculus.

    Unless you are doing a very rough estimation close to a Go/NoGo test.

    Is the light bright, dim, very dim, or off.

    Having said that, here is the irony, I do actually make a battery tester that uses halogen bulbs.

    Edit, and those are not normal car headlight bulbs. And there is more "stuff" than just bulbs.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	IMG_8951.jpg 
Views:	38 
Size:	494.4 KB 
ID:	722555  
    Last edited by Fluffy; 2024/05/18 at 09:51 PM.
    Cheers

    NAGOF

    HAM Callsign - ZS5KAD

    Freedom of speech is useless unless you allow people you don’t like to say things you don’t like………

    If you fly or drive to an anti-Fracking meeting, you have no business being there and you wont get my ear......

  24. The Following 2 Users Say Thank You to Fluffy For This Useful Post:


  25. #38
    Join Date
    May 2009
    Location
    Hillcrest
    Age
    67
    Posts
    24,599
    Thanked: 20832

    Default Re: Testing battery capacity

    Quote Originally Posted by cliftf View Post
    It was 11.95 when I disconnected, and immediately went to 12.2. When I checked a few hours later it was 12.6v
    You do know that 12.6V at rest is somewhere around 70-80% SOC on Lead acids.
    Cheers

    NAGOF

    HAM Callsign - ZS5KAD

    Freedom of speech is useless unless you allow people you don’t like to say things you don’t like………

    If you fly or drive to an anti-Fracking meeting, you have no business being there and you wont get my ear......

  26. The Following User Says Thank You to Fluffy For This Useful Post:


  27. #39
    Join Date
    Oct 2009
    Location
    Kempton Park
    Age
    41
    Posts
    2,718
    Thanked: 5210

    Default Re: Testing battery capacity

    Just get a NL battery monitor. You can then get a rough idea at rest and under load. Ive been using it for years and although very rough and primitive ive learned when to expect a blackout.

    Edit: dont complicate a simple lead acid system with too many questions. Its like cheap tools, it works fine until suddenly it doesn’t.
    Last edited by LandyLove; 2024/05/18 at 09:49 PM.

  28. The Following 2 Users Say Thank You to LandyLove For This Useful Post:


  29. #40
    Join Date
    May 2009
    Location
    Hillcrest
    Age
    67
    Posts
    24,599
    Thanked: 20832

    Default Re: Testing battery capacity

    Quote Originally Posted by LandyLove View Post
    Just get a NL battery monitor. You can then get a rough idea at rest and under load. Ive been using it for years and although very rough and primitive ive learned when to expect a blackout.
    Rough and primitive but extremely useful once you understand your baseline.
    Cheers

    NAGOF

    HAM Callsign - ZS5KAD

    Freedom of speech is useless unless you allow people you don’t like to say things you don’t like………

    If you fly or drive to an anti-Fracking meeting, you have no business being there and you wont get my ear......

  30. The Following User Says Thank You to Fluffy For This Useful Post:


Page 2 of 3 FirstFirst 1 2 3 LastLast

Bookmarks

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may post attachments
  • You may edit your posts
  •