I have a Victron Smart 100/30 MPPT charge controller currently running a 320 watt solar panel and I will be adding a second panel making it 640 watts.
The panels lay flat on an RV roof, not pitched so I don't believe they will ever put out the rated specs.
Each panel is 45.3 volts and 9 amps max output, they will be in series making it 9 amps max and 90.6 volts max.
Is is possible to continue using the 100/30 since both together do not meet or exceed the 100/30?
The 100/30 spec is 100V max input voltage and 30A max output current.
If you are charging a 12V system then at say 14V charge voltage 640W could produce a current of 46A so your 100/30 will not be able to produce the full output. However, Victron do allow you to put more panel power on and the controller restricts the output. You will have 50% more panel power than the controller can deliver. I think this is OK but you need to check.
If you have a 24V system then the charge current will be 23A so OK.
The 100V input is a hard limit, if the panels exceed this the MPPT could be damaged irreparably. At low temperatures the panel voltage increases. Look on the panel datasheet to see the temperature coefficient for the voltage and your lowest temperature to see if 100V could be exceeded.
