0 Ohm resistance

Thread Starter

Iodem_Asakura

Joined Sep 14, 2004
140
I thought that a 0 ohm resistance was used as a fuse, but i'm begining to doubt about it. Could someone light me up about this? Is it used as a fuse or a jumper? How much current does it support?

Thanks for your help.
 

Dave

Joined Nov 17, 2003
6,969
You will find that a fuse actually has low resistance, which is not 0Ω. The fuse is designed as the weakest point in the circuit and will blow first if there is a current surge over the rating of the fuse. Up to the fuse rating the fuse mateial acts merely as a resistive element dispating power in the same way as resistor would.

The only example I know of with (effective) 0Ω resistance are superconductors: Information on Superconductors
 

kurios

Joined Sep 29, 2005
14
well according to me what i have studied and observed is that the fuse do have some resistance but not equal to 0. bcoz i it have 0 resistance then why not we use the direct wire instead of using fuse.... just think over it

secondly, the fus has some resistance but that resistance is soo much low with respect to the load resistance that it can be said as ≈ 0Ω hence the fuse blows first whenever current than the normal ratio as fuse provides the easiest path (due to it's low resistance)
 

Sebi

Joined Sep 24, 2005
59
The zero ohm "resistor" (marked with one black stripe or on SMD "0") used as jumper. This method simple for automatic assembly.
 

Thread Starter

Iodem_Asakura

Joined Sep 14, 2004
140
Thanks that was what i was talking about, the zero ohm resistor (the one marked with an only stripe of black color). Then the answer is, that it is used as a jumper, eh?

Do you know how many current does it support? I have only seen it in oine size.
 

rjenkins

Joined Nov 6, 2005
1,013
The type we use are rated by the manufacturer at:

25A @ 25'C linearly derated to 0A at 150'C
(These have a body 7mm long x 2.5mm diameter, lead 0.6mm diameter)

I think it's basically the rating of the wire they are moulded around..
 

Dave

Joined Nov 17, 2003
6,969
Originally posted by Sebi@Nov 24 2005, 10:13 AM
The zero ohm "resistor" (marked with one black stripe or on SMD "0") used as jumper. This method simple for automatic assembly.
[post=11910]Quoted post[/post]​
I've not come across them before.

To back up what rjenkins is saying, check here.
 

chulomex

Joined Dec 1, 2005
4
Zero Ohms are usually used as jumpers. Sometimes there are paths that you may want to add to an already built board and you would really like to have a way to add that part of the circuit later. Then all you do is put a placeholder for the resistor but don't put anything in. When the time comes that you need to add that part of the circuit all you do is install a Zero Ohm resistor and now the other path is working as well.
 
Top