Most MPPT controllers will limit their maximium current
to protect themselves, although I am not a great fan of relying on this mechanism in the long term. MPPT controllers are not the most reliable electronics
, even when kept within their specifications.
The Victron MPPT have some restrictions on this protection mechanism. For the 100/30 they warn that damage may occur if the PV short circuit current
is over 35A. You don't mention the specific solar panels
that you are using, but with "12v" panels at 480w they may be close to the limit, so it is worth checking. I would certainly be happier with the 150/35 or the 100/50. The latter will have more headroom
and room for expansion. It may also be cheaper despite the higher current rating, as the provision for a higher input voltage needs expensive components.
Better still, as others have recommended, would be to use a single
controller for each panel, or as you have six panels, one controller for two panels. Without knowing the details of your panels it is hard to recommend the correct controllers, but the idea is to replace one 150/35 with say three 75/15. This will provide slightly more output, as the MPPT will be more accurate, and it adds some redundancy. The main drawback is more complicated wiring
. The cost is often similar to a single
larger controller, but this is dependent on the specifics.
The only other thing to consider is that the Victron units have a high start up voltage. Thus they are probably not a good choice for those 12v panels with lowish Voc, especially if you are in hot conditions. It is not clear if the practical effect of this limitation is significant. Some more detailed user reports would help. Certainly I am happier recommending the Victon units for high voltage panels, or at least 12v panels that have a Voc on the high, rather than the low side. Once again, details of your panels would help.