When is a resistor shorted

As in a series circuit, a short in a parallel circuit will usually cause an open circuit by blowing the fuse. But, unlike a series circuit, one shorted component in a parallel circuit will stop current flow by causing the fuse to open. Refer to the circuit in Figure If resistor R3 is shorted, a path of almost zero resistance will be offered the current, and all the circuit current will flow through the branch containing the shorted resistor.

This topic This board Entire forum Google Bing. Print Search. Pages: [ 1 ] Go Down. Author Topic: Resistors - do they short or do they open? Read times. Once a resistor becomes faulty, perhaps through excessive current and heating, does it generally open, or does it sometimes short, or does it mostly short, or is it random?

This is speaking of standard resistors, I understand that some resistors intended to be used as fuses exist too. Related, but a different question would be also can a notable permanent change in resistance occur if the resistor is 'overdriven' but not to the point of "breaking", i.

I understand that resistance changes with temperature, but don't know if a permanent change is also possible. In case there are videos about these things that I've missed I watched some that show resistance change with temperature temporarily, but that's all , I would love to check them out as well. Update: I forgot to do the search first.

It might turn out that this has been asked millions of times. A resistor seldom fails short. If it is getting hot enough to fail, a short would typically dissipate even more power and cause the material to ignite or explode. That being said, there are some resistor constructions, like the bifilar wire wound used for low-capacitance and low-inductance special resistors that could short out internally.

In network circuits, short circuits can occur between two phases, between phase and neutral or between phase and ground. It is probable that such short circuits generate a very high current and, therefore, rapidly activate an overcurrent protection device. However, short circuits can occur between neutral conductors and ground and between two conductors in the same phase.

These shorts can be dangerous, especially because they can not give rise to a high current and, therefore, are less likely to be detected. Possible effects include the unexpected activation of a circuit that is supposed to be isolated. To help reduce the negative effects of short circuits, power distribution transformers are deliberately designed to have a certain amount of leakage reactance.

A short circuit can lead to the formation of an electric arc. The arc, a channel of hot ionized plasma, is very conductive and can persist even after significant amounts of original material have evaporated from the conductors. Surface erosion is a typical sign of damage to the electric arc.