. Not just to the same earth ground. There must be a *short* ground wire from the cable and phone entry protectors to the ground at the power service. Without a *short* wire, high voltages can develop between power and phone/cable wiring, as illustrated in the IEEE guide starting pdf page 40. A service panel suppressor provides NO protection from these high voltages. In that case the IEEE guide says "the only effective way of protecting the equipment is to use a multiport [plug?in] protector." Many houses have cable and phone entry points too far from the power service (or connected incorrectly).
That is one of the reasons for the quote from the NIST guide at the top. .
. Poor w_ just keeps repeating the same drivel and his religious mantra.
Still never seen - a source that agrees with w_ that plug-in suppressors are NOT effective.
Still never answered - embarrassing questions:
- Both the IEEE and NIST guides say plug-in suppressors are effective.
- The only 2 examples of protection in the IEEE guide use plug-in suppressors?
- The NIST guide says plug-in suppressors are "the easiest solution"?
- SquareD says "electronic equipment may need additional protection by installing plug-in [suppressors] at the point of use."
- Why does the IEEE guide say for distant service points "the only effective way of protecting the equipment is to use a multiport [plug?in] protector."
For real science read the IEEE and NIST guides. Both say plug-in suppressors are effective.