question

skip-gundlach avatar image
skip-gundlach asked

More than 50A potential into a 50A controller?

Hi - and my apologies if this is a duplication of a question asked without my having found the sub-group MPPT controllers:

I'm having to replace my controller for my 2x360W Sunpowers, run in parallel, with blocking diodes on the + legs.

Voltage ~70, max, and current (combined) ~13, max, from these panels at full output.

The most - and that only once, briefly - I have ever seen is 50A output. Yet, in perfect conditions, I MIGHT get 60A.


Can I use a 50A controller safely?


Thanks.


MPPT Controllers
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

3 Answers
wkirby avatar image
wkirby answered ·

Yes. The MPPT controller will limit the battery current to 50A without problems.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

rickp avatar image
rickp answered ·

Yes, the Victron SmartSolar SCCs are named by “PV Voltage Max Input/SCC Max Output.” So the SmartSolar 100/50 would allow some leeway on your input voltage, and limit max charge output to 50A.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

dazey77 avatar image
dazey77 answered ·

The best way I have heard it described is

-voltage limit is a hard limit on the input. If it is exceeded, even in rare cases you can kill the controller (so a 75v one would not be recommended for you)

-current limit is a soft limit on the output. You could use a 15A output with your setup and it would work fine, but you would only ever get 15A out, so it would be a waste. Over panelling a controller is sometimes useful if you don't need more than xA in summer but want to still get something out of it in winter.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.