I have a room with 2 ungrounded (2-prong) outlets and 1 switched grounded (3-prong) outlet. This has not been a serious inconvenience so far, as most of the equipment I wish to connect has ungrounded plugs and I can leave the switched outlet on. However, it would be nice to have the protection of a surge protector on more of my equipment, which requires a ground connection.
(I am renting, so let us assume for the purposes of this question that having the outlets replaced is not an option.)
For this purpose, I can imagine using a “2-prong to 3-prong” ground adapter to connect a separate wire run to the ground of the switched outlet (using another appropriate adapter, assuming such exists, to connect to the ground terminal with low risk of hot/neutral contact, or perhaps running to the outlet screw as a ground adapter would).
- I would ensure that no 3-prong equipment is plugged into the surge protector connected this way (e.g. label and cover the ground pin sockets). This would hopefully eliminate the risk of loss of the safety ground (except for the surge protector itself).
- I would verify that the 3-prong outlet does in fact have a ground. (Adequate testing would be a different question.)
- Is this safe?
- Is this useful? (That is, would the unusual pattern of wiring somehow interfere with the function of the surge protector?)
- Is this permitted?
I'm not especially committed to this solution; it's just a thought that keeps coming to mind, and so I want to know how bad an idea it is.
I am in California, USA.