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Temp Compensation Trojan T105

I have 2 Trojan T105 6v connected for 12v. BlueSolar MPPT 75/15. The controller was automatically set at -29.5mV/F. I live in Phoenix, AZ where temps are often 100+F. However, this is for a Travel Trailer, which will be used in much cooler temps 30-80F.

I am was concerned about my charger not reaching the float voltage. I think it's related to the Temp Comp. I'm wondering if this is what's going on. Charger is currently on Float @ 13.2v. Float is set at 13.5v. I live in AZ, current temps are 95-100F. Temp comp is set at -29.5mV/F. My Absorption is set at 14.83v. My history shows a max of 14.58v for the last 3 days. There has been a day that was 13, and another that was 14.83v. But 14.58v is the most consistent reading.

So I think my math correct on this?

13.2 + 0.295 = 13.5.

14.58 + 0.295 = 14.875


That said, the data sheet says subtract 0.0028v per cell, per degree above 77F. 0.0028 x 6 cells = 0.0168v. Easy math, temp was about 87f at dawn. So 10 x 0.0169 = 0.169. So wouldn't the correct setting be -16.9mV/F? The data sheet also says to ADD 0.0028v per degree below 77F. If the temp at dawn is 37F, shouldn't the Temp Comp be set at 67.6mV/F?

Am I supposed to calculate and set the Temp Compensation each time I go camping for the current weather? Or am I just supposed to set it at one setting and the controller will adjust accordingly?

MPPT Controllerstemperature compensation
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