Solar conundrum (updated with shopping list)

smkettner wrote:

clotus wrote:
Do you guys think I should go with a PWM charger, or spend the money now for a MPPT charger? I am looking for a good 3-stage charger that I can adjust the charge voltage. I like the idea of the bogart controller. I was also looking at the Blue Sky and Mourning Star chargers. I want to spend the money now as opposed upgrading later.

Read the Bogart manual for available settings but I think it will do everything you need. My perception is Morningstar is a level up vs. Blue Sky if you choose one of these.

With just two batteries and around 300 watts of 12v panels you will have plenty of power. I see MPPT for larger systems with 24v panels, 4+ batteries, large inverter etc. The MPPT does not extract as much extra as they would have you believe. Most claim 30% boost but that is only when the battery is super low. During most of the charging time the boost is closer to 5% as bulk ends and 0% during absorption.

The 30% they claim is just a estimate , if you charge at 14.4 volts 30% of that is 4.32 + 14.4 is 18.72 which is a normal range of panels
It depends on what type of battery you have your controller set to charge at and at what level of charge its in , bulk, absorption , float, equalize , that would determine the diff between a PWM and a MPPT , the MPPT uses all available voltage in bulk stage ,in the others its likely to be using more most times as well , its capable of it , it depend on the battery state and what it requires at the given time
I have 4 interstate 6 volt GC2 232 amp hr battery's that require 13.6 in bulk , 14.4 in absorb ,13.7 in float , 15.10 in equ
The Morningstar Tristar MPPT TS-RM-2 remote panel does every function you need and shows battery states at all levels , amp hrs , amp hrs used , watts , watts used ....
I have a PWM on my TC and its fine , its a mater of cost per system , what you need per system and how much you want to get per dollar you spend , if you use a PWM and think later you might change to a MPPT be sure you can use the wireing and breakers .... or your going to spend more in the long run doing it twice