well since it is -24c outside and have nothing to do. I thought I show how my system using emontx shield is setup using my gti limiter and diverter sketch and the 6 port digital pot controller attached - and considering with net metering getting harder to achieve as electric companies in North America and else where make it nearly impossible/ cost prohibited, or no longer allowed here was my solution to my particular problems. perhaps someone will find it useful in their project
as a rule of thumb size every thing to 60 - 70%. ie if you your working in 36 volt and your GTI is 1000 watts. them use a 40 amp PWM or if it micro GTI at 300 watts then 20amp is fine . same applies to isolating diode if you need a 10 amp use a 15 amp or a 20 if you need a 50 amp use a 75 or a 100amp.
but you can set it up with out the GTI limiting function if you like and it will work fine it just that the batteries will take priority if drained naturally then once the batteries are in the float stage most of the solar production will go to the GTi anyway. . I just like the GTI limiter function . because if all my battery banks are full or the water tank is at maximum temp . then it simply shift the GTI power production down lower . but also useful if you have time of day tariffs ie smart meter) it can adjust a GTI that connected to a battery to output just the right amount of power to keep your High price energy usage to a minimum then charge the batteries at night using low cost energy.
for my solar water pump I set the power supply to come on at night when the pump runs during the winter. it not really needed but do it just because winter months can have very little sun at times , and this way it ensures that my batteries are in always nearly full in the winter time in case of extended power outage … but all in all if there is no power I can go 3 days of no sun before the the batteries run dry. if there is some sun i can run indefinitely. so I am very pleased about that…considering it is pumping about 3000 gallons of water each and every day continuously which is enough water for about 8 households