I need to know the best approach to begin testing a PCB circuit that I know nothing about. What are the various precautions to take to avoid frying any components? Guidelines and general steps would be very much appreciated. Also, information on any source I can consult would be appreciated.

 

Much like you, we know nothing about the PCB. It would really help if you could give us something to work with.

 

The best approach to begin testing a PCB Circuit is to find out what is the input and output power requirement of the circuit.

 

The question is a hypothetical one that I was asked. It does not have to do with any particular board. It was asked to see what steps I would take to test/figure out a new board without frying it. Things like wearing a static wrist strap, figuring out maximum voltages and the like.

 

When faced with a totally unknown circuit, the best approach that I have found is to use logic.
Sense, Decide, Act.
Most circuits have defined voltage requirements.
Find the power source & check it first.
Most circuits will have inputs. That is the Sense.
Most circuits will process the inputs. That is the Decide.
Most circuits will output according to the two above. That is ACT.