Eric Greenwell wrote:
Doug Haluza wrote:

Current flows in a complete circuit--direction is arbitrary and
irrelevant. What actually happens in many cases of applicance damage is
not voltage surges, it's ground potential difference. If your power,
telephone, cable TV and water services do not enter at the same point
and have common grounding, they can have different "gound" potentials
relative to each other. Even if lightning does not strike your house
directly, it disturbs the ground potential for a large area. This is
why telephones, televisions and refrigerators with ice makers are often
damaged--they are connected to two different systems.

If the surge protector has a cable or phone jack connector in addition
to the AC sockets, would that protect the TV or telephone?

It is helpful to have a common surge protector for low energy
disturbances, but it cannot completely make up for a lack of proper
bonding in a high energy situation. For example, if the telephone guy
drove a separate ground rod, and it is not bonded to your power service
ground, your $10 surge protector is not going to survive a nearby
strike.