"leza wang" wrote in message
...

my home is like 70 or even more years old (not sure really). I want to
know if i should upgrad the wiring. the electrical panel shows i have
100 amp. I have been told if i have knob 2 wiring then i should change
it to 3 knob wiring. My question, how can I know if i have 2 knob
wireing or 3? in the main floor, i have all power outlet with 2 holes
(+,-) upstair I have power oullet with 3 holes (+,-, ground)
Thanks a lot.

Call an electrician (or even several) to get your wiring inspected and get a
quote on upgrading if it's needed. Even if they charge you a few bucks for
an inspection you'll at least know what you're dealing with.