Battery Rating vs Capacity Monitoring
Some things: Shipping batteries in the US requires the Watt-Hour rating to be marked on the battery, and the rule is to use the "nominal" voltage. So LFP uses their 12.8v figure for that 100AH x ...
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I tried out the Trimetric but my load was via inverter, so that kind of confuses things. I would rather just have big enough DC load like the furnace, but that was not convenient today. Another time.
anyway, the Trimetic swap to watts from amps was easy, and it did not change the AH reading, so it does not do Wh, only AH.
I want to see if the watts came to a different amount with the same amps when the battery was lower in SOC, but the inverter got in the way.
Starting with full 200AH pair of 100AH G27 SiO2 (much like AGMs) and using the "700w" MW as a load on the 2000w MSW inverter and taking into account whatever wiring zoo I have in the set-up, I got:
-12.1 loaded voltage and 700 watts at first, and 725w after two minutes.
-12.1 loaded voltage and 62.8A at first, and 63.3A after two minutes.
63 x 12.1 = 762.3
Ran the batts down more to get a lower voltage to go with the amps. Down 28AH - about 86% SOC (the Trimetric's % SOC not being used for this)
-11.8 loaded voltage and 913 watts swapped to
-11.8 loaded voltage and 77.0A allowing for time to swap the display.
77 x 11.8 = 908.6
I don't have the desired same amps to go with different watts I would like to test for, but
12.1/63 = 0.153, and 11.8/77 = 0.192 so the proportion of amps per watts is different, but I don't know how much is due to the non-resistive MW load with the inverter action mixed in.
So I think I need to use the furnace to see what I want next time camping when the batts will also get down to a much lower SOC. so the two sets of numbers will be outside any testing margins of error too.
If anybody can make sense of the numbers I did get, please share! Thanks.
anyway, the Trimetic swap to watts from amps was easy, and it did not change the AH reading, so it does not do Wh, only AH.
I want to see if the watts came to a different amount with the same amps when the battery was lower in SOC, but the inverter got in the way.
Starting with full 200AH pair of 100AH G27 SiO2 (much like AGMs) and using the "700w" MW as a load on the 2000w MSW inverter and taking into account whatever wiring zoo I have in the set-up, I got:
-12.1 loaded voltage and 700 watts at first, and 725w after two minutes.
-12.1 loaded voltage and 62.8A at first, and 63.3A after two minutes.
63 x 12.1 = 762.3
Ran the batts down more to get a lower voltage to go with the amps. Down 28AH - about 86% SOC (the Trimetric's % SOC not being used for this)
-11.8 loaded voltage and 913 watts swapped to
-11.8 loaded voltage and 77.0A allowing for time to swap the display.
77 x 11.8 = 908.6
I don't have the desired same amps to go with different watts I would like to test for, but
12.1/63 = 0.153, and 11.8/77 = 0.192 so the proportion of amps per watts is different, but I don't know how much is due to the non-resistive MW load with the inverter action mixed in.
So I think I need to use the furnace to see what I want next time camping when the batts will also get down to a much lower SOC. so the two sets of numbers will be outside any testing margins of error too.
If anybody can make sense of the numbers I did get, please share! Thanks.
