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5A fuse for a 0.6A led strip? (if i did the math correctly)

RAinbowMAker

New Member
Hi,
I want to connect an LED strip to my car's fuse box for a clean installation.
In the product description page, it detailed 12V and 8W which is 0.6666A the way I understood it.
So it means I need a 0.666A fuse? Which is not a thing. But neither was I able to find anywhere to purchase 1A or 0.5A low profile mini fuses.
Is it alright to use a 5A fuse? That is the lowest one I've got.

Thanks!


*Product Link:
 

rjenkinsgb

Well-Known Member
Most Helpful Member
The important thing with fuse ratings is that they are lower values than the rating of any wires or cables that run from them.
Strictly speaking that is what all normal fuses are for - to protect from things taking excess current that can overload wiring and cause it to catch fire if a fault occurs.

As long as all the wires and connections are rated at 5A or more, a 5A fuse should be OK.

For info, you can get "mini blade" type car fuses down to 2A, I've got an assorted pack with 2, 3, 4, 5 & 7.5A in it.
eg. https://www.halfords.com/workshop-t...orted-mini-blade-fuses-2-3-4-5-7-5-amp-hfs214
 

rjenkinsgb

Well-Known Member
Most Helpful Member
How can I know how many amps the connections are rated at?
You have to look up the wire specifications in a standard table, but you need to know the wire construction to do that - the number of strands and size of each strand.

The safest thing to do for your application would be add an inline fuseholder that can take something like a 20mm x 5mm cartridge fuse, as near as practical to the fusebox. You can easily get fuses such as those in lower ratings.
 

RAinbowMAker

New Member
Thank you for your answer!

Quick questions though:
1. Are there any risks I might run into when trying to plug it with a 5amp fuse directly to the fuse box?
2. Can I plug 2 black wires (ground? not sure of the terminology) on top of each other? I also have a dashcam connected to the fuse box.

Thanks again!
 

rjenkinsgb

Well-Known Member
Most Helpful Member
It appears you are using a piggyback "fuse tap", I can see one in a photo you posted earlier.

As long as the circuit you tap off is rated reasonable high, that should be fine.
Only fit the upper fuse first (your 5A one) and make sure your new device works - if it does not, the tap is the wrong way around. Then fit the original fuse in the lower position.

For grounds, try to fit them on a metal bolt that is directly in to metal parts, so you get a good connection to the chassis.
Clean off any paint immediately next to the bolt hole so there is bare metal, eg. for an area like a washer.

I usually fit a crimp eyelet terminal the appropriate size for the bolt or screw, plus adding shakeproof washers ("Star washers") both above and below the terminal eyelet.
The sharp edges on those cut in to the metal and help ensure a good connection. Put vaseline over the metal to prevent rust.
 

RAinbowMAker

New Member
Thank you, again. I'll definitely try to get my hands on some shakeproof washers and eyelets!

But I'm still not quite sure what "the circuit you tap off is rated reasonable high " means. Is there a way for me to know that?
 

rjenkinsgb

Well-Known Member
Most Helpful Member
But I'm still not quite sure what "the circuit you tap off is rated reasonable high " means. Is there a way for me to know that?
You piggyback in to something like a 20A or 30A fuse circuit, not another 5A one - just to be sure the connections feeding the fuse can take some extra load.
 

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