What is a Zero Ohm Resistor and What is it used for?
This article is about zero-ohm resistor, its uses, and the reason why it is known as a resistor even though its resistance is zero Ohm.
Zero Ohm Resistor
A zero-ohm resistor or also known as a zero-ohm link is a resistor that has zero-ohm or approximately equal to zero ohm resistance. Its resistance is almost near to 0Ω. It is simply a wire or a jumper in the package of a resistor. As wires are normally avoided in PCB designs. Hence the alternative solution is to use a zero ohm-Resistor.
Zero-ohm resistors are either surface mount or wire-wound. A surface mount zero-ohm can be identified by a labeled zero on the resistor as shown in the figure below.
A wire-wound zero-ohm resistor can be identified very easily because there is only one black band on the resistor, as shown in the fig below. This single black band shows that it is a wire wound zero-ohm resistor.
The reason it is known as a zero-ohm resistor instead of calling it a conductor is because it has some tolerance.
Why Zero Ohm Resistor is used?
The question is that what can be the use of zero-ohm resistor? Why not just use a wire as they both have approximately zero resistance?
The main purpose of using a zero-ohm resistor is that most of the components in PCBs are inserted by automatic machines. Sometimes it is necessary to short out two points in a PCB. A manual solution is to use a jumper, but automatic insertion machines can only handle components. A separate machine will be used for injecting jumper wire or it can be injected manually by a person. So, instead of using separate sources for injecting wire jumper, a zero-ohm resistor is injected through an automatic insertion machine.
Another advantage of using a zero-ohm resistor is that it can be replaced very easily.