Load Testing a pair of T-105's
Can anyone provide numbers that you have recorded so I can compare to see if my pair are in the ballpark? Im getting about 10 hrs @ 10 amps to 50 percent level... I just replaced a pair that after...
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Taking them down to 10.5v over 20 hrs would be very hard on the batteries. That is a 100% DOD.
EDIT--I see that was 10.5 loaded when the inverter shut down, so it would have not been as much "resting voltage" after bounce back.
You can get the capacity close enough by just going down to 50%, which is the usual recommended limit. (Of course you can get away with going lower but you aren't supposed to make a habit of it)
It is supposed to be linear for discharging, but I find it speeds up a little from 75-50 compared with 100-75. Got to keep an eye on the SG getting close to 50 or you will overshoot easily.
If using 12v lights as your load, you do have to add another light part way through to maintain the 20 hr rate, as lights dim and draw fewer amps as battery voltage declines. If using inverter as the load, it is the opposite, where the inverter pulls more amps as battery voltage declines. Start with just under the 20 hr rate and end up just over so it averages out roughly, close enough--it doesn't have to be exact for this test to be able to tell how your batteries are doing.
EDIT--I see that was 10.5 loaded when the inverter shut down, so it would have not been as much "resting voltage" after bounce back.
You can get the capacity close enough by just going down to 50%, which is the usual recommended limit. (Of course you can get away with going lower but you aren't supposed to make a habit of it)
It is supposed to be linear for discharging, but I find it speeds up a little from 75-50 compared with 100-75. Got to keep an eye on the SG getting close to 50 or you will overshoot easily.
If using 12v lights as your load, you do have to add another light part way through to maintain the 20 hr rate, as lights dim and draw fewer amps as battery voltage declines. If using inverter as the load, it is the opposite, where the inverter pulls more amps as battery voltage declines. Start with just under the 20 hr rate and end up just over so it averages out roughly, close enough--it doesn't have to be exact for this test to be able to tell how your batteries are doing.
