I am writing to comment on the article, "One-hour Project--Updating Wall Electrical Outlets," by Michael J. Presutti, printed on Page K9 (Jan. 7).
The instructions critical to adding three-prong electrical outlets are so vague as to be lethal. A single instruction is offered for actual ground connection. It reads, " . . . and fasten a special wire from the little green terminal located at the bottom of the receptacle."
It does not indicate where to connect the special wire (on the new socket), or explain what is "special" about the wire. It implies that the green terminal is always at the bottom of the receptacle. In fact, it may be at the top, on either side, or not exist at all, depending on the electrical codes prevailing when the house wiring was installed.
More significantly, most homes built before about 1960 do not have receptacles (wall boxes) with such a ground terminal. Homes from this era were typically wired with two (not three) conductor conduits providing no earth ground lead. Such installations exist throughout the greater Los Angeles area.
In such situations, it is necessary to install a ground wire from earth ground to each receptacle. This is best done by a qualified electrician.
VAN O. WRIGHT
(Editor's note: We received several calls and letters from readers pointing out, as Mr. Wright does, that the article--because of vague wording and the unstated assumption that the electrical system being worked on was a grounded system--could create a potentially hazardous situation. In response to those calls, The Times published a correction on Page A3 on Tuesday, and we thank those readers who alerted us.)