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Muddydogs's avatar
Muddydogs
Explorer
Aug 28, 2015

Hydrometer reading questions.

Just got the hydrometer and have a question about the thermometer attached. When it says add 2 its .002 so a reading of 1.260 is 1.262?

Tested an Interstate SRM 24 battery that has been setting for 5 days. Voltage reads 12.78 and cell SG reads 1.255, 1.260, 1.270, 1.260, 1.260 and 1.255 with an add 2 for temp going from + to - posts. From what I can find this battery should have an SG of 1.275 when 100% charged.
  • NinerBikes's avatar
    NinerBikes
    Explorer
    Aug 29, 2015
    If your experiences mirror's others here, you'll find out how hard it is to equalize charge one of these batteries and get the SG up where it belongs, at about 1.275 or better for all 6 cells. Pretty sure you have sulfation with SG numbers like that.

    A few equalization charges, and you may just shorten the learning curve and get some real deep cycle batteries, the 6v kind, instead of these imposter deep cycle cells.
  • BFL13's avatar
    BFL13
    Explorer II
    Aug 29, 2015
    It could be 100% charged at its now lower capacity (sulfated somewhat) and show proper voltage but the lower SG.

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