[hugz]

I'm finally casing up my DIY Firstwatt F2. I'll be doing it mostly in steel. The PSU is already connected to the earth. Should i wire the case up to the earth too?
 
Thanks
 
Hugz

 

[gimble]

You don't have to, but it improves its effectiveness as a shield significantly.
 
Make sure you *earth* it...sometimes designated grounds appear in a circuit schematic which should really not be connected to chassis ground.

 

[balderon]

It is often recommended to keep chassis (earth) and circuit grounds separate and install a ground loop breaker between chassis ground and circuit ground. I use a 10 ohm 1W wirewound resistor in parallel with a 0.1uF 250V capacitor to couple the two.

 

[hugz]

Oh thanks. My initial concern was that earthing the case would effectively short the case to the psu earth. sounds like your suggestion solves that worry

 

[hugz]

Okay and lets expand this some more.
 
The large case will enclose the transformer, PSU board and the audio board.
 
I was already planning to case the transformer in its own little steel enclosure inside the larger case. How would you best wire it for the best shielding? Earth both the transformer case and outer case, or just earth one?

 

[nikongod]

If the case has mains power going into it (or in the case of many power amplifiers, possibly lethal voltages - anything over 30V), it should be grounded to the IEC ground for safety. 
 
What you do with signal ground is a matter of taste, art, and science.