The recommended way to ground amatuer equipment is by running an individual
ground wire to a main grounding point or to a point that has a larger wire,
and even a heavy strap that some run around the shack if you have a large
shack. One thing I urge in regards to ground and grounding. If you homebrew
equipment and plan on running both 220volts and some 120 volts in the design
of the amp and supply, It is now manditory accoding to National electric
code 1996 edition, but has always been considered good practice to use a
separate nuetral wire brought in rather than using the bond (ground) as a
return for 120 volt loads. The code specifically states that only fault
current should flow on the bond wire or bond system back to the main panel.
Also for those of you installing your own sub panels for shack supply, your
feeder from your main panel must include a separate bond wire and the bond
and the nuetral wires should not come together in the sub panel! If you use
BX then it has already been done for you. But if you use romex be sure to
install a SEPERATE Bonding bar for your bond wires, Do not mix nuetral and
bond wires on the same bar in a sub panel. Unfortunetly most panels Main Lug
or Breaker DO NOT come with a separate bonding bar, It must be purchased
separately. This all sounds trivial and it will work fine the other way, but
the National Electrical Code requires this separation in sub-panels. Its
best to do it by code, just in case a problem should arise!!! Also DO NOT
when building amps, ground the primary of a filament transformer (120v) to
the chassis as a nuetral return!!! Use a separate wire connected to the
nuetral of the electrical supply wire. The 1996 code now, NO LONGER allows
ranges and cloths dryers to share a common bond/nuetral connection as in the
past. The new code requires a 4 pin plug where as in the past a 3 pin plug
was used. Better to be safe than sorry................73 LOU
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