[TenTec] Centaur Power Cord

[Jim Brown K9YC]

On Sat, 5 Jan 2008 21:34:00 +0200, Geoffrey S. Mendelson wrote:

>Not here, the hot lead is 230 volts, the neutral is neutral and ground is
>a saftey ground.

That's because YOUR power system, like those in EU, is an unbalanced 230V 
system -- or 230-0-230 for larger loads. The North American power system is 
120-0-120. Ordinary loads are unbalanced, from one of the 120V lines to 
neutral. 

As others have noted, it is NEVER acceptable for a green wire (safety 
ground) to carry load current. That is true in EU, it is true in North 
America, and it is true elsewhere. 

The green wire is a SAFETY ground -- it is present so that it can blow a 
fuse or breaker in the event of an equipment fault that causes the chassis 
of equipment to be "hot" and kill someone who touched it. 

It is NEVER safe to connect neutral and ground at equipment, or to connect a 
load between "hot" and the safety ground, and it also causes serious noise 
problems. The reason is that when equipment is wired properly, all the load 
current flows "out" on the "hot" conductor and returns on the neutral (or, 
in the case of a 240V load in North America, out on one "hot" and back on 
the other "hot." In those conditions, the FIELD associated with the load 
current is confined to a small area between and immediately surrounding 
those wires. If the neutral were to be grounded at the load end, return 
current spreads out between all of the ground paths between the source and 
the load, and the FIELD associated with that current is large and spread out 
over that area. This kind of wiring fault is a VERY serious one, and a MAJOR 
cause of noise, both at baseband (power and its harmonics) and RF (power 
supply hash, switching transients, etc.). 

For additional discussion of this see the Power and Grounding tutorial on my 
website. 

http://audiosystemsgroup.com/publish

73,

Jim Brown K9YC