"Serge Auckland"

Sensible advice, but isn't it a pity that consumer electronics rarely
follow professional practice of having a permanent safety ground, and a
separate audio ground which can be bonded to safety ground or lifted.


** Shame how in very case where that is seen it is VERY unsafe !!

Floating the internal circuitry while grounding the external metalwork of
AC powered audio gear is a recipe for a FATAL accident.

Think it trough.

Humans touch the connectors that link to that floating circuitry.



Don't understand the problem.


** That was bleeding obvious already.


The metal case is permanently connected to the safety ground. The power
supply transformer laminations are also grounded to the case. The
transformer secondary floats, as does all the audio circuitry. No
different to double-insulated appliances where nothing is grounded.


** OK - so YOU have no *****ing idea* what the safety rules are for
an appliance to qualify as "double insulated" as well as NO idea what the
safety rules are for a fully earthed appliance.

In the latter case - the simple rule is that ALL exposed metalwork
capable of coming into contact with a person must be connected to the safety
ground.


With SMPS,


** Yawn - not one bit relevant.






........ Phil