[TowerTalk] bonding to AC power box or inside fuse panel?

[Jim Brown]

On 1/21/2013 3:27 PM, Joe Subich, W4TV wrote:
>
> On 1/21/2013 6:13 PM, vk3pa at vk3pa.com wrote:
> > I run rf earth separated from the Power ac supply service no
> > connection between the two.. de vk3pa
>
> Not good practice in the US.  Power supply ground (as opposed to
> neutral) and RF earth ground should be the same.  Otherwise any
> lightning induced surge on one or the other will result in a voltage
> difference between the the two which *will* equalize by moving current 
> *through* the chassis of any equipment connected to both the power
> supply "safety" ground and the RF ground.
>
> This is a recipe for significant lighting or power supply induced
> damage.  *Always* bond the RF ground and the power "entrance" ground
> together via a path that *does not* place any equipment between the
> two "grounds".

Joe is absolutely right.  What VK3PA is describing is VERY unsafe, and a 
recipe for disaster. It is also illegal in most parts of the world, 
including VK.

There are at least three critical reasons for bonding everything 
together. First is lightning safety, as Joe has described. Second is 
protection of humans from electrical shock in the event of equipment 
failures -- a solidly connected ground (earth) is required to blow 
fuses/breakers. Third, proper bonding minimizes hum and buzz problems 
when equipment is interconnected.

73, Jim K9YC