Posted by felixcct on 11/15/57 11:39

w_tom wrote:
> If his problem was solved by a surge protector, then nothing in the
> player would function. Furthermore, a surge protector "in series" is a
> myth. Plug-in protector promoted by people who don't even know what a
> surge protector does. A protector that 'looks' like it is between a
> VCR/DVD player and AC electric is really only in parallel. A
> destructive transient hits protector and player simultaneously. Since
> players already have internal protection, then a trivial surge may not
> damage the player - and yet fully vaporize the typically undersized
> protector. Trivial surge struck both equally and simultaneously. But
> only grossly undersized protector failed - provided ineffective
> protection.

Actually this is not quite a correct version of how a surge protector
works.

Real surge protectors typically have the following specifications:
1. Peak voltage allowed to pass
2. Response time to respond to over-voltage
3. Maximum energy sinked to ground before destruction

When a voltage spike arrives at the surge protector, if it exceeds the
peak limit, the surge protector will drop to very low resistance and
begin diverting the current to ground. The response time is critical in
determining how much of the spike's energy will reach the protected
equipment. It's not the voltage of the spike that matters, it's the
total energy that gets through - i.e., voltage x current x time, with
the time being the critical factor that's up to the surge protector.

Surge protectors also have a maximum energy capacity. If it is
exceeded, the surge protector will be destroyed, which may allow
additional energy to get through to the now-unprotected equipment (but
hopefully by then a line fuse or breaker in the current loop will have
opened). Many types of surge protectors are intended for one-time-use -
if they divert a surge, they are permanently affected, and need to be
replaced.

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