WHY THE +VE POLARITY OF 48V DC POWER SUPPLY IS USUALLY
GROUNDED?
Answer Posted / neeraj singh
Sorry, but this:
"negative because - it reduces the chances of Noise ,, as
noise tends to add more towards +ve signal "
is garbage. Electrical noise picked up on a conductor is not
affected by the potential of the conductor.
This too is drivel: "as in higher DC voltages , one may
stick to the conductor ( In higher AC however you may be
thrown off )"
It's an old wives tale, nothing more. When subjected to a
shock, your muscles contract. In an Ac shock, they do not
contract and expand at the line frequency (50/60Hz).
Generally if you get a belt to the hand, your arm folds at
the elbow and your fingers close. That may throw you off, or
it may close your grip... ac or dc makes no difference.
| Is This Answer Correct ? | 3 Yes | 1 No |
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