Am I asking to much from 2x T105's?

marcindy wrote:
I posted a month or so ago about my new solar install, and some issues I was having with the low voltage alarm on my Xantrek 2000W Prowatt while running my coffee maker (Tassimo). I was able to check a little closer this time with a DMM, and confirmed that the E01 alarm (low I/P voltage) was coming on around 10.8V (not over 11 as originally thought)- although it was a little hard to hold the probes which running the coffee maker- either way, I think the inverter is working as expected (I think).

My question, is should 2x T105's be able to handle a 100-125A load for a minute or 2? I'm running 2/0 AWG, 2-3 ft in length. The batteries are on the 3rd season. I don't have much room on the tung of my HTT, but can probably get 4x T105's.

I'm not planning any changes this year, but in the spring may make the change. The microwave also sets off the low voltage alarm.

Thanks in advance
Marc

yours is a pretty typical experience IMHO for a pair of GC batteries. The biggest downside to GC is that the design isn't meant for current draws that high, 75A/bank is about the max w/o a significant voltage drop. Internal resistance is higher than 12V and with 12V you usually have at least two in parallel so each battery is supplying much less current. I run a 1000W inverter for my microwave and with 2 GC batteries needed to be at75% SOC or more to not trip the low voltage cutout,and that is with about an 80A draw. Now I have 4GC and it isn't near as much an issue.

If your bank can't handle the current load with something above 75%SOC, I suspect either battery problems, or wiring voltage drop or both. Certainly by 90% SOC it should work. The problem arises as you get below about 75%SOC and by 50% SOC your probably out of luck with that level of current draw.