What size fuse.

Neckender

Neckender

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As You all know I've recently installed a 100watt solar panel with 10 amp controller, what size fuse would you recomend down at the battery end, 15amp, 20 amp or any other size.

Thanks for yor help.

John.
 
The size of the fuse must be less than the current rating of the cable you have used.
 
trikerman said:
As You all know I've recently installed a 100watt solar panel with 10 amp controller, what size fuse would you recomend down at the battery end, 15amp, 20 amp or any other size.

Thanks for yor help.

John.
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I think this is right :)
Amps = Watts / volts so theoretically your panel can provide 8.3 amps. a 10amp fuse should do the job.
 
shortcircuit said:
I dont see how. The fuse is there to protect the cable and if you do not no the size of cable then you cannot suggest a size.
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One would hope that he has read your first post about the cable and has the correct cable for his panel , But regardless if he fits a fuse lower than the panel is going to supply it will blow anyway. Chicken and Egg the 2 go together IMHO and both should be suggested together.
 
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biggirafe said:
One would hope that he has read your first post about the cable and has the correct cable for his panel , But regardless if he fits a fuse lower than the panel is going to supply it will blow anyway. Chicken and Egg the 2 go together IMHO and both should be suggested together.
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And what about the power the battery will supply back up the cable in the event of a fault in cable?
 
shortcircuit said:
And what about the power the battery will supply back up the cable in the event of a fault in cable?
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But 10 amp is still the smallest fuse you can fit (well 8.33 but they don't make those). Hense having the fuse at the battery end but you know this.....
 
biggirafe said:
But 10 amp is still the smallest fuse you can fit (well 8.33 but they don't make those). Hense having the fuse at the battery end but you know this.....
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Assuming they are spade fuses

Box of Car Spade Fuses

Set of 80 fuses for automotive use.

Contents

* 10 x 3A Fuses
* 10 x 5A Fuses
* 10 x 7.5A Fuses
* 10 x 10A Fuses
* 10 x 15A Fuses
* 10 x 20A Fuses
* 10 x 25A Fuses
* 10 x 30A Fuses
* 1 x Tool


The fuse must be less than the rating of the cable and not just what is available
 
shortcircuit said:
Assuming they are spade fuses

Box of Car Spade Fuses

Set of 80 fuses for automotive use.

Contents

* 10 x 3A Fuses
* 10 x 5A Fuses
* 10 x 7.5A Fuses
* 10 x 10A Fuses
* 10 x 15A Fuses
* 10 x 20A Fuses
* 10 x 25A Fuses
* 10 x 30A Fuses
* 1 x Tool


The fuse must be less than the rating of the cable and not just what is available
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No one is disagreeing with you, but the fuse must also be large enough to cope with the current produced by the solar panel. Its not a radio or similar that is just going to 'suck' power it is also going to produce power (if the sun ever shines).

If his solarpanel produces 8.3 amps then the fuse MUST be bigger than this even your list above shows that 10amps is the smallest vehicle fuse he can use.

But I'm bored with this if you don't get it now you never will :)
 
biggirafe said:
No one is disagreeing with you, but the fuse must also be large enough to cope with the current produced by the solar panel. Its not a radio or similar that is just going to 'suck' power it is also going to produce power (if the sun ever shines).

If his solarpanel produces 8.3 amps then the fuse MUST be bigger than this even your list above shows that 10amps is the smallest vehicle fuse he can use.

But I'm bored with this if you don't get it now you never will :)
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Unfortunately its not boredom but failure to comprehend.

If the cable has to deal with whatever output from the solar panel it must have a rating to carry the current supplied. At the battery the fuse must be rated to be below the rating of the cable but above that of the anticipated output of the panel otherwise you risk serious consequences in the event of cable faults it will "suck power" from the battery, big style.

I trust you now comprehend
 
Thanks Biggiraf, and shortcircuit, I have used the proper cable the same as comes with solar panel, so I will fit a 10 amp fuse. The reason I've asked the original question is a mate of mine is a auto electrician and he supplied and fitted fuse holder only, and he has fitted a 30amp spade fuse which I considered was to big. so thanks again guy's, didn't mean for you to fall out though.

John.
 
trikerman said:
Thanks Biggiraf, and shortcircuit, I have used the proper cable the same as comes with solar panel, so I will fit a 10 amp fuse. The reason I've asked the original question is a mate of mine is a auto electrician and he supplied and fitted fuse holder only, and he has fitted a 30amp spade fuse which I considered was to big. so thanks again guy's, didn't mean for you to fall out though.

John.
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I am glad its been of use to you although a bit long winded. My logic was to explain why, rather than blindly fit an incorrect fuse.

Life is to short to fall out about minor issues
 
I may be missing something here, but why do you need a fuse at the battery end?

bev
 
trikerman said:
Thanks Biggiraf, and shortcircuit, I have used the proper cable the same as comes with solar panel, so I will fit a 10 amp fuse. The reason I've asked the original question is a mate of mine is a auto electrician and he supplied and fitted fuse holder only, and he has fitted a 30amp spade fuse which I considered was to big. so thanks again guy's, didn't mean for you to fall out though.

John.
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if your m8 is an auto-electrician then surely its his job to know what size fuse is adequate! so y did he fit a 30amp?:confused:
 
The auto elec should have checked but it may well be like the 13 amp plugtops that all come with 13a fuse and you are supposed to fit to suit appliance and how often does that happen?
 
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