Can this damage a switch?

[Rubycon]

If an ethernet cable gets caught in something and all the conductors short together? Or say someone takes a pair of dikes to the wire and cuts it - while still plugged in. Can it kill the port?

 

[imagoon]

Most switches are high impedance and shouldn't have an issue but i wouldn't put it past some of the cheap junk out there.

 

[cmetz]

Rubycon, neither of these should kill the port. 10BaseT/100BaseT/1000BaseTX are all quite low voltage for signalling (+/- 2.5V max), and ports are supposed to have some serious transient input protection (I think it's 1,000V). A lot of the cheap gear doesn't really comply with the input protection spec, but still, it's unlikely that the 2.5V signal from another conductor would be a problem.

 

[Mark R]

It's unlikely, if that is all that happened. The inputs/outputs are transformer coupled and current limited.

External sources of voltage (or even PoE), or excessive ground loop currents, however, could potentially be conducted back to the port, and damage the transformer, or if they have fast edges, be coupled through and damage the electronics.

 

[Rubycon]

Thanks guys, I figured it would be OK but these switches are expensive to repair.

 

[alkemyst]

I know some older 3COM switches will fry the ports if shorted. Also if you are using a POE switch there could be a lot more watts moving down. A good switch should be able to handle a short though.