Fuse or Switch? What goes first?
- Thread starter solarrig
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timselectric
If I can do it, you can do it.
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Fuse before the switch, also protects the switch.
Fuse after switch, allows for safer Fuse replacement.
Most pre-made combiner boxes have the Fuse first.
I would probably prefer switch first.
But, It's not a big deal either way.
Fuse after switch, allows for safer Fuse replacement.
Most pre-made combiner boxes have the Fuse first.
I would probably prefer switch first.
But, It's not a big deal either way.
By the way... how this fuse can work? My solar panels max amperage is 13.40A. Short circuit current 14A. And in the manual they say: "Maximum series fuse rating - 25A". So how these 25A can be reach, as with the short it only makes 14A?! 
And what fuse should i put there? 13.90? :D Bigger then max A, but lower than short? i'm lost at this moment
And what fuse should i put there? 13.90? :D Bigger then max A, but lower than short? i'm lost at this moment timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
- Messages
- 18,619
This fuse is for protecting the panels. They have been tested to handle 25a without damage.By the way... how this fuse can work? My solar panels max amperage is 13.40A. Short circuit current 14A. And in the manual they say: "Maximum series fuse rating - 25A". So how these 25A can be reach, as with the short it only makes 14A?!
If you had 3 strings in parallel. And one string developed a short. The other two strings could send a combined 28a (14 + 14) . This is why you are only required to have a fuse if the rest of the circuit can exceed the panels rating. Usually it's 3 or more strings, for the requirement of a fuse per string.
Now it's clear !!
thank you !
