• 03|March

    Morning Low ::12.63 | < 12.63 | < 12.39     Yield :: 1.54K | 1.01K | 610 || 600 | 320 | 160

    31st March :: ML V=12.60   Y=1.92KWh
    30th March :: ML V=12.64Y=1.73KWh
    29th March :: ML V=12.54Y=1.87KWh
    28th March :: ML V=12.58Y=1.79KWh
    27th March :: ML V=12.64Y=1.90KWh
    26th March :: ML V=12.59Y=2.02KWh
    25th March :: ML V=12.51Y=1.73KWh
    24th March :: ML V=12.50Y=1.75KWh
    23rd March :: ML V=12.51Y=360Wh
    22nd March : ML V=12.51Y=600Wh
    21st March :: ML V=12.52Y=350Wh
    20th March :: ML V=12.52Y=460Wh
    19th March :: ML V=12.69Y=1.27KWh
    Checked battery electrolyte level and all plates were covered. Added approx 2.2Lt 90ml per cell
    The ML drops : see https://unveiled.info/solect/specific-gravity-1

    18th March :: ML V=12.78 :: Y=560Wh Given ML of 12.78 will check battery electrolyte level
    17th March :: ML V=12.51Y=1.32KWh
    16th March :: ML V=12.58Y=220Wh
    15th March :: ML V=12.66Y=280Wh
    14th March :: ML V=12.51Y=460Wh
    13th March :: ML V=12.39Y=1.36KWh Incubator lamp all night
    12th March :: ML V=12.44Y=610Wh Incubator lamp all night
    11th March :: ML V=12.44Y=1.41KWh Incubator lamp all night and day
    10th March :: ML V=12.43Y=1.21KWh Incubator lamp all night
    9th March :: ML V=12.47Y=670Wh Incubator lamp all night
    8th March :: ML V=12.44Y=440Wh Incubator lamp all night
    7th March :: ML V=12.47Y=1.35KWh Incubator lamp all night
    6th March :: ML V=12.36Y=430Wh Incubator lamp all night
    5th March :: ML V=12.48Y=510Wh Incubator lamp all night
    4th March :: ML V=12.30Y=840Wh Incubator lamp all night
    3rd March :: ML V=12.48Y=190Wh
    2nd March :: ML V=12.62Y=460Wh
    1st March :: ML V=12.50Y=890Wh
  • Old ELF setup


    Fri 7th I connected one panel, via the Steca Controller, to one old battery. Used it as load battery and measure a use of 10Ah total.

    Could see from the Steca the Asus 900 uses 1 amp

    Sat 8th Since then I have 2 old 50w panels connected via the Steca to one old battery. The other old battery I have topped up with water, which was a bit iffy as it was a sealed battery. The six cells needed about a litre so hardly surprising it/they were almost unrechargeable.

    That battery as end of day on the 9th was rated as 52% charged, by the next morning is was 48%

    Switched old battery. Bat I received 25Ah charge via Steca and was at 80% when disconnected.

    Connected two old panels and one new REC max charge rate was 4.4 of 6.8 generated? Will fill with water tomorrow.

    Bat 2, filled with water 2 week ago, was at 3% charged at connect. It rose to 12% at sunset, 15% by 2100 hours and 18% now at midnight. 19% at 0100 How ??????

    At 0900 theSoC reads 23%??? and now at 1200 the sun is up but it is overcast 0.6A charge, 12.8v Soc 25%

    Tue 2nd Dec 1140 Soc 54%

    Jan 1st 2015 Soc 61% however the battery seems to be discharging quite rapidly down from 80% two days ago. I should check there are blocking diodes in the each of the two panels.
  • Hydrometers Intro

    I have ended up buying two hydrometers. I first called Plymouth Battery Centre who informed me they had a glass model at £19 which I thought was a bit expensive so when I went to town I thought I'd look around before I took the mile or more walk to Prince Rock.

    The Toolshed could get a glass model for £5 and the car shop next door had the same model for £2.99, which I bought. When I went to the Plymouth Battery Centre to buy some red and black covered multi-core cable I decided to buy the hydrometer they had anyway, which cost £14.50 eventually.

    The better model from Plymouth battery Centre is the one on the left, although you cannot see the coloured scale. It is supplied by Gordon Equipments under the name DURITE model 0-070-00 ; range 1.15 to 1.40; accuracy 0.01. All parts are individually replaceable.

    The difference in readings is notable.

    Concerns regarding the cheapo

    1. The float diameter is much smaller than the container diameter so the readings are at an angle.
    2. On the side of the container the float rests, the surface tension of the acid draws the liquid further up the side of both, giving a distorted view.
    3. The scale is on the small side so not so easy to read.
    4. And of course there's the idea that the calibration is off.
  • Battery Resistance

    For lead Acid Batteries

    There are two processes where the battery resistance will change.

    a) The normal operation of charging a battery will increase it's resistance, whilst removing sulfation, and the resistance will drop as sulfation occurs. This follows the formula that V=I × R.
    With a constant current (I) the battery charges the voltage (V) rises. Is simple terms as an equation must balance then if one side increases then so must the other. So if V rises then I &times R must also rise and of I is constant then R must rise. The reverse is the case when the battery discharges.

    b) Although sulfation and de-sulfation are the normal reactions in a lead acid battery sulfation can become ingrained and not subject to being processed by normal charging. In this case the battery appears charged and has a high resistance. To overcome this, or at least to try to, a high voltage can be applied in an attempt to force the sulfate to return to the electrolyte.

  • Specific Gravity

    A lead acid battery will have a ration of sulfuric acid and water as the electrolyte. The process of charging forces any sulfate from the battery plates back to the electrolyte which increases it's specific gravity. The specific gravity of pure water is set at 1. By dissolving substances in water makes if heavier per volume. The common amount of acid brings electrolyte specific gravity (SG) to 1.128 approx.

    Measuring the SG with a hydrometer can show if the acid is in the plates and they are sulphated.

    The two times this would occur is a) in the normal process of discharging and b) in the longer term build up of sulphated plates that do not respond to a normal charge and the battery is termed 'sulphated'

    The SG will also vary on the level of electrolyte as the water evaporates. As water evaporates the SG increase along with ration of acid to water. Adding water will lower the SG and show the battery is not as fully charged as it may seemed when the electrolyte was lower than the designed level.

  • 02|February

    ML>12.69 or Y>1.23K | ML<12.63 or Y<320 | ML<12.39 or Y<199

    28th February :: ML V=12.52 :: Y=520Wh
    27th February :: ML V=12.55 :: Y=1.79KWh
    26th February :: ML V=12.52 :: Y=1.80KWh
    25th February :: ML V=12.38 :: Y=1.74KWh Left router on all night ??
    24th February :: ML V=12.54 :: Y=1.58KWh
    23rd February :: ML V=12.50 :: Y=1.46KWh
    22nd February :: ML V=12.50 :: Y=1.23KWh
    21st February :: ML V=12.52 :: Y=1.18KWh
    20th February :: ML V=12.52 :: Y=360Wh
    19th February :: ML V=12.37 :: Y=930Wh
    18th February :: ML V=12.51 :: Y=1.02KWh
    17th February :: ML V=12.44 :: Y=530Wh
    16th February :: ML V=12.48 :: Y=150Wh
    15th February :: ML V=12.44 :: Y=980Wh
    14th February :: ML V=12.56 :: Y=1.58KWh
    **After 9 weeks topped up batteries:** None of the plates were exposed but did use the best part of 5Lt
    **EQUALIZING**By setting Absorption and Float to 16v
    **EQUALIZING**Although ABS set at 15.64 which was reached around 9:30am by 13:00 v has dropped to <15.4 though set at 16v. Again I am inclined to consider resistance is dropping and undoing some of the sulfation
    13th February :: ML V=12.51 :: Y=670Wh
    Although I reset the mppt after midnight it created two records by 09:20 so I reset it again and noted the ML and consumption
    12th February :: ML V=12.64 :: Y=220Wh
    Updates and Firmware updates were carried out between 16:30 and 16: 50 and there was no recorded yield since.
    The values in both columns headed today and yesterday are those of the 12th. I will be resetting the datafile soon to avoid visual errors.

    11th February :: ML V=12.64 :: Y=610Wh
    10th February :: ML V=12.43:: Y=830Wh
    9th February :: ML V=12.43:: Y=550Wh
    8th February :: ML V=12.52:: Y=160Wh
    7th February :: ML V=12.50:: Y=760Wh
    6th February :: ML V=12.63:: Y=750Wh
    5th February :: ML V=12.63 :: Y=100KWh
    4th February :: ML V=12.65 :: Y=560Wh
    3rd February :: ML V=12.54 :: Y=890Wh
    2nd February :: ML V=12.67 :: Y=1.17KWh
    1st February :: ML V=12.62 :: Y=410Wh