Thank you for your invaluable reply.
Got other question regarding this issue as well.
I bought an American manufactured PlayStation 2 console. The manual book says, this console runs at 120V AC, 60Hz but this console was sold at UK, hence there will be power conflict. Therefore, this console was packed with a power adaptor. At the back of that power adaptor printed: AC input 220V
50Hz, AC output 100V 58W. Read the PS2 manual book (US) attentively, power adaptor is not included but a simple wire meant for direct connection between the socket power supplier and the console.
Question 1: Assuming this console is to be used in America. A simple wire for direct connection between socket power supplier and the console? Does this mean, that console has an internal power adaptor that steps down the voltage as it runs at 120V 60Hz?
Question 2: Assuming this American product is to be used in UK with a power adaptor as mentioned above. If Question 1 is true, then there will be two power adaptors, one internal and one external. External power adaptor steps down voltage from 220V to
100V according to its back plate. Since that console runs at 120V as stated on the manual book, how is it possible for it to run at 100V? And the external power adaptor runs on 50Hz, how does it communicate with that console (120V 60Hz)??? What is the usage of that internal power adaptor over here????