Helping a friend setting up a project and got a couple of questions -
1. he's getting a good deal on thin film modules. while i recommended him using crystalline modules because thin films have very high voltage and complicates system design, not to mention additional system cost on rack support etc, he really loves the look of it. anyway, the 100W amorphous module has the following spec -
The system will use 48V battery and we got this MPPT charge controller that operates from 16V~112V with maximum 140VDC input. Now I know that this is drawing a bit too close to limit to be using this controller, but I don't have a lot of experience with thin films (esp the change in performance over time) and since our weather is pretty warm most of the time (always >25'C), I'm not worried about the voltage spike seen in cold weathers. What do you guys think, is this a good idea?
2. "Batteries should not be connected in more than 3 parallels". I was told this by a salesperson of batteries but I don't really buy it. I know connecting parallels can be tricky in terms of having the same (or similar) distance from each battery paralleled to point of output, so each battery can be drained more or less the same, but why the magic number 3?
As usual thanks for any help in advance - you guys are great (esp. BB!)