Thanks guys for the info, I will try to make things more clear.
1. I made sure that the bulk and absorption settings are the same.
2. what I have described in my first post is considering the same conditions, sunny day between 11am to 3 pm, similar partial shading(backstay) as usual, same behavior for a year , noticed every day, this has been going on since I first installed the system and it has been working in the same way for a year now, I just always wondered why I wasn't getting that proper charge of about 350-450 watts during the bulk stage.
3. I have checked all the connections a few times and nothing wrong there.
for example on a normal sunny day:
Just as the sun is rising my battery voltage is about 12.4 V, and since the sun is very low I am only seeing about 5 amps, 62watts, Bulk stage,which I expect.
by about 11 am, my battery is about 13.2 V , I am getting 16amps,211watts, Bulk,on average.
It will continue that way for a few hours while the battery voltage creeps higher to about 13.8V , still showing about 16amps, 220W, bulk
when the battery voltage reaches about 14.4V or higher at around 2pm, the
mppt switches to absorption mode , then I start getting more amps suddenly, about 25amps, and reading about 360W or more.
this sudden increase in performance of the
charging system only happens after the batteries have been charging for a while and the mppt switches from bulk to absorption.
shouldn't I be getting the same type of performance of about 25 amps and 360W earlier on in the day when the sun is high and its in Bulk stage around 12 noon?
I always thought is was a case of what MarkJ mentioned in his Third point but thought I would make sure with you guys.