electrostatic & leakage issues in electronic circuits

[rajaram04]

Hello sir
so many times we observed a "humm" or some misbehaviour of electronic circuits caused by leakage currents earthing problem or some static electricity by vicinity . . so how to protect this things ? or say how to make proper sheilding ?

how we can low down humm or noise or effecs of static elect. ?

please comment . . thanks

 

[Audioguru]

In your home or in a business there is 50Hz or 60Hz mains wiring all around you. The voltage of the mains electricity is high so it causes interference. Any unshielded wires are antennas to the interference. Audio and video equipment use shielded connecting cables that block the interference.

 

[rajaram04]

In your home or in a business there is 50Hz or 60Hz mains wiring all around you. The voltage of the mains electricity is high so it causes interference. Any unshielded wires are antennas to the interference. Audio and video equipment use shielded connecting cables that block the interference.

hm i see , & what about earthing problem in a metallic cabinet ??? usually i observed that all negative or earth terminals has to connect on a single point . . why so ?

 

[Audioguru]

A metal cabinet is usually connected to the circuit's 0V, which is not always earthed.
All grounds of the circuit should connect together at a single point to avoid "ground loops" that might cause hum and distortion.

 

[rajaram04]

ground loops you mean ?