40A MEGA fuse in LYNX for 24V system? Common or doable?

Sprks

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Trying to determine if using the LYNX and its MEGA fuse requirements, for my 24V system design is good/doable. 24V = smaller cabling which i like. Clean in/out of LYNX i also like. But smallest MEGA fuse i can find is 40A which = 10AWG, which is also fine. 60A MEGA/8AWG might be OK, but pushing limits on component connector cable size limits. 40A fuses seem relatively uncommon only one i can find is on AMZ https://www.amazon.com/2-Mega-Fuses...1647901151&sprefix=40+amp+mega,aps,200&sr=8-2 and doesn't list the voltage... I have searched here on the forum and found a couple of posts with one possible LYNX adaption to MIDI fuse's, but haven't found much else in anyone doing this 40A MEGA/LYNX combo. ANY help/wisdom/experience would be appreciated for this beginner. Thanks!
 

Sprks

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What is limiting the cable size limit?
Is it a mechanical lug on a component, solar charge controller perhaps?
Yes, Victron 100/20MPPT says 10AWG. On a side note MPPT also says 30A fuse max.... so is it still "size fuse to the wire" = no MEGA/LYNX ? Am still hoping for some real world experience in anyone successfully using the MEGA/LYNX with 40A fuses. AND if the 40A fuses in my link above are reliable. Again, thank you!

PS Clarification request for this beginner. Is it always "fuse to the wire" and if so i can use larger fuse that component fuse requirement?
 
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PS Clarification request for this beginner. Is it always "fuse to the wire" and if so i can use larger fuse that component fuse requirement?
If Victron says max 30 amp fuse then that is what you should use.
Wouldn't want to void the warranty.
Typically it is "fuse for the wire" but there are exceptions and this is probably one of them.
 
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If it were me I would use pin terminals on the solar charge controller and use 6 awg with a 100 amp fuse :)
 

Sprks

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If it were me I would use pin terminals on the solar charge controller and use 6 awg with a 100 amp fuse :)
"if it was up to you" means you would forego the 30A max fuse and use 100A/6awg on this MPPT...? I do appreciate the Ferrules link resource.
 
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may i ask your reasoning why you wold do this?
I bet that solar charge controller will be upgraded before long.
6 awg with a 100 amp fuse can be repurposed.
6 awg with a 100 amp fuse will cover a lot of other uses.
 

mikefitz

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Victron recommended a 30 amp fuse at the battery end of the feed cable. This will protect the the feed cable and the Victron internal wires/components from over current. Using a 100 amp fuse may/will not protect the Victron.

Whilst the common statement, "the fuse protect the the wire ", is used, you also have to consider what is connected to the end of the wire.

In this case using an additional 30 amp midi fuse and holder would seem to be the easiest option.

Mike
 

Sprks

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Apr 1, 2021
Messages
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Victron recommended a 30 amp fuse at the battery end of the feed cable. This will protect the the feed cable and the Victron internal wires/components from over current. Using a 100 amp fuse may/will not protect the Victron.

Whilst the common statement, "the fuse protect the the wire ", is used, you also have to consider what is connected to the end of the wire.

In this case using an additional 30 amp midi fuse and holder would seem to be the easiest option.

Mike
Simple solution and exactly why this beginner so appreciates this forum. Thank you!
 
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