question

The MPPT can't overcome panel physics. Shading a third of a bank is going to have a bad effect on generation, lowest common denominator. No MPPT firmware can fix that.

As soon as one (or more) panels of one string are in the shade, the bypass diodes of the shaded panels should start conducting. So you if you have 9 panels of 415 watt on a string and 2 panels are shaded, you should still be able to see close to 7 panels output, the two shaded panels are short circuited by the bypass diodes. IF this does not happen, the mppt is not getting the maximum power out of the remaining string.

I also own an mppt rs450 200 and i also see weird mppt behaviour. It's like the mppt is not scanning wide enough or with a too low resolution. It doesn't want to move. Example: fully clouded, stable condition, then sudden sunlight (lasting one hour), mppt's don't move for a long time or even shut down to a very low wattage. i haven't measured it exactly yet, but i have seen mppt's perform way better for sure.

I bought the unit to have the best MPPT on the market... so far, not impressed. I've read other entries on this forum that state similar findings. I hope this is not a HW restriction, and that it's fixable by SW.

This is NOT GOOD as Andy would say ;)

I agree with you basco.

When 2 Modules are shaded the output is far less than the remaining rest of the modules - Voltage rises, the MPPT would have to scan deeper so that the bypass diodes open up.

Daniel

I can confirm the same issue on both of the 450/100 "MPPT"s that I installed.

Due to this, the effective power production is only a fraction of what it should be and was modeled before commissioning, which is costly in missing power.

I have reported my issue to this thread, adding it to other similar reports.

It has been confirmed by Victron as the new algorithm needing improvement and being worked on:

https://community.victronenergy.com/questions/229322/mppt-rs-450-shadow-management.html