Sparks between external HD usb cable and Mac Pro case

[Courthold]

Hi all,

I just wanted to see if anyone could say how usual (or not) this was - basically I noticed that as I go to plugin a usb cable which is connected to a powered external HD, any contact between the cable connector and the metal case of the mac cause little sparks.

I haven't noticed this before, although it's possible I was just more precise with my plugging ability

I had a search of the forums but all I could find was reference to the laptops or an iMac.

Thanks!

 

[philipma1957]

It may have been static electric sparks. My home uses forced air heat and i have had static sparks touch the gear with my hands or with a usb cord with my finger just on the metal a bit.

 

[diazj3]

It may have to do with your electrical installation - my guess is that the MP and HD are not connected to a properly grounded circuit.

My advice is to check it ASAP.

Cheers!

 

[mjsmke]

This happens on iMacs too.

Another funny thing is if you switch a printer on, unplug the usb cable from the Mac and hold the metal end, run your fingers along the metal of the iMac you can feel some static or something. Maybe this is the same with all metal cased computers? It might be that the case is the earth of the computer.

 

[StructAural]

This happened to one of my front ports on my Mac Pro and the port no longer works....the one above it does though...