I've seen balanced power used to reduce noise in audio systems. There is an argument for this, as it does work (although if your equipment employs proper grounding practice, there will be very little advantage). But I also think there are risks involved.
The reason for the risk is that normally the fuse for any audio equipment is on the hot side of the line and is the first thing the AC power encounters on its way into the unit. This BTW is required to get UL approval, the CE mark and generally, certification for import into nearly any country in the world. The fuse is in series with the AC power switch. In this way, if the switch is shorted to the chassis (damaged in shipment for example) it can blow the power fuse.
If for some reason the other side of the AC line (neutral) gets shorted to the chassis, nothing happens, as the neutral is connected to ground (which should be where the chassis is connected). In this situation nothing will happen.
But if you are running 'balanced' power (the correct term BTW is 'symmetrical' power), what was the neutral side of the AC line is now hot with half of the line voltage on it. So if it gets shorted to chassis, potentially (pardon the pun ) the chassis will be live and could be quite dangerous.
I don't see any protection fuses (of which the values would have to be chosen by the user, there being a fuse for each outlet) on any of the symmetrical power products I have seen. But I've not seen all of them. Has anyone else seen this? I do not see a GFI being enough protection in this case...
So- what am I missing, or am I seeing something that others are not??
The reason for the risk is that normally the fuse for any audio equipment is on the hot side of the line and is the first thing the AC power encounters on its way into the unit. This BTW is required to get UL approval, the CE mark and generally, certification for import into nearly any country in the world. The fuse is in series with the AC power switch. In this way, if the switch is shorted to the chassis (damaged in shipment for example) it can blow the power fuse.
If for some reason the other side of the AC line (neutral) gets shorted to the chassis, nothing happens, as the neutral is connected to ground (which should be where the chassis is connected). In this situation nothing will happen.
But if you are running 'balanced' power (the correct term BTW is 'symmetrical' power), what was the neutral side of the AC line is now hot with half of the line voltage on it. So if it gets shorted to chassis, potentially (pardon the pun ) the chassis will be live and could be quite dangerous.
I don't see any protection fuses (of which the values would have to be chosen by the user, there being a fuse for each outlet) on any of the symmetrical power products I have seen. But I've not seen all of them. Has anyone else seen this? I do not see a GFI being enough protection in this case...
So- what am I missing, or am I seeing something that others are not??