Calling on Solar Techies
I have been thinking of going solar for some time and decided to pull the plug. My wants are a 400 to 500 watt system. I have four 12 volt batteries with 340ah. I am not planning on changing b...
Forum Discussion
SJ-Chris wrote:1L243 wrote:
I installed a Aili battery monitor. (it'similar to the Renogy monitor) It asks for the total ah's in the battery bank (340). It uses this as a base when calculating +/- ah's.
Assuming you never want to completely drain the batteries to 0 ah's should I put in the total amount assuming the monitor takes this into account or half the total ah's?
I have the same battery monitor (Aili). You want to program it to your TOTAL AH, not 50%. If you set it to 50% it will cause a problem if you ever get to "0%" and keep discharging. The problem is this.... Once the meter gets to 0% it will not go any lower (it won't go negative). So let's assume at that point your SOC is at 50% (and your monitor says 0%). Well....let's say that it's the middle of the night when this happens and you've got your furnace blasting, etc and you end up draining another 20% of your battery bank (...not likely in your case, but just for illustrative purposes). So now your SOC is actually at 30% (and your monitor still says 0%). Once you start charging, your monitor will immediately start going up from 0%. Let's say you charge it all the way back up to what the monitor says is 100% full and you stop. Since you actually started at 30% SOC and not 50% SOC your batteries are really only at 80% SOC even though your monitor says 100%.
This problem doesn't happen if you program your Aili monitor to show 100% of your battery bank's AHs instead of just half.
Hope that makes sense.
With this monitor (and I suppose most monitors), anytime you truly charge the battery bank back up to 100% (ie. hooked up to shore power for a few days, or if you have solar and park it for storage with everything powered off), then your monitor is once again synced up to what is truly 100% fully charged.
Happy Camping!
Chris
Thanks for that information Chris. I did put in the total amount of 340 Ah in the meter. I have not had it long enough yet to see how how long it takes for the battery to drop from 100%. So far I have only got to 99%
