a … yes Australia … 
You probably wouldn’t be allowed to drive 5km with such a body here in Europe … 
2x2 did not require series fusing.
I would like to see faces of the german policemen.
He’s lucky. We have tooooo many rules in the EU.
Police : What do you have on the vehicle?
What do you think … Oh well … I’m transporting solar cells on my roof rack …
Police … hesitantly … ok … Have a good trip
1x4 requires series fusing?
@Netrange what are those? Yoy didn’t mention me anything like that…did you? What are those?
Lol
I would like to know that too …
You actually secure a solar string individually.
In your case it would be the 15A mentioned for a 1x4 arrangement.
With a 2x2 arrangement, you could use “inline fuses” … these are already installed in the solar cable … possibly a space decision
It is the reverse current that a panel (inc cables) can handle before it melts or catches fire.
Looking at my panel, it has a series fuse rating of 10a.
Should 1 panel have a fault, the other 3 panels could dump the Isc of 5.48a x 3 into it.
Yes, If you remember the left drawing of my parallel connection from the first topic…I had 15A inline MC4 fuses on the + right before the cable splitter. I took them off when I connected the into series.
But I am not sure why should we use it in series? Isn’t those blocking diodes are for the parallel connections of solar panels?
In series connection I thought there are the bypass diodes which are already built into the panels by the manufacturers. Did I miss or misunderstood something here?
With these relatively small currents, you can argue about fuses …
This is more about the “deactivation” of the PV modules for mppt … if work were necessary.
With plastic superstructures such as the motorhome, short circuits to the chassis can hardly occur.
Defective solar modules in a series connection do not technically lead to a problem … There is simply no more current flowing.
In a 2x2 group connection, the functioning modules “consume” the current in the module that has the short circuit.
In your case, that would even be 15A … so a fuse for the PV modules would not be necessary at all. The main switch in the “curtain room” would only be for disconnecting … but not for the safety of the modules …
I am a bit confused here…they say if the short circuit current of the entire solar array is greater than the panel’s max series fuse rating then each string must be fuses right before the splitter and the each fuses need to be sized to match with the max series fuse rating. But this rule is for parallel connection, isn’t it?
Okay okay…but what did @water_rat he mention? I still don’t understand it…
The same guy … maybe he will bring light into the darkness … have a look
… first Comment …
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I know…I saw this video at least 10 times.
He was my source before you:smile: and this forum came into my life.
Looking at your data sheet.
The panel has an Isc of 10.74a. And a series fuse rating of 15a.
Should 1 panel short out, the other 3 panels could dump 3 x 10.74a into the damaged panel.
IT IS NOT GOOD THAT THE SPEC SHEET MIXES UP WITH short circuit voltage and Isc.
How should 3x Isc be “consumed” in a series connection?
Only a maximum of 1x Isc flows through all panels … because it is a series connection.
If a module is defective internally … then either no current flows at all or 1 x Isc is “short-circuited”
In parallel, of course, this is something completely different
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Yes. Yes. Yes. I’ve learned from the videos exactly what just you explained here. Then I am not confused anymore. 
Yes parallel is a concern for series fusing. (between panels/strings)
Looks ok, but as @pwfarnell mentioned, you will need a 150v mppt.
What battery voltage required?