Lack of ground indicator

Claim 2

In an electrical pluG including a body of insulated material, a first and second prong secured in said body, a ground prong in said body, said prongs being electrically insulated from each other, the improvement comprising a resistor electrically connected between said first prong and said ground prong; and said electrical plug having a single indicator means, said indicator means being electrically connected between said second prong and said ground prong whereby said first prong is connected to a positive power line, said second prong is connected to a neutral power line, and ground prong is connected to a ground line, and said indicator means is activated upon the absence of a ground.

Claim 3

An electric plug as in claim 1 wherein said ground prong is an automatically retractable ground prong.

Claim 4

An electric plug as in claim 1 wherein said indicator is enclosed by said body and said body has an aperture for exposing a portion of said indicator.

Claim 5

An electrical plug for connecting a three-conductor cord to a grounded electrical receptacle comprising: a body of insulated material attached to said cord; a first and second prong secured in said body and electrically connected to a hot and a neutral conductor of said conductors, respectively; a ground prong in said body and electrically connected to the remaining conductor; and only a single indicator circuit including said prongs and consisting of a resistor in said body electrically connected between said first prong and said ground prong, and an indicator means in said body connected between said second prong and said ground prong for indicating absence of grounding of said remainder conductor when said plug is inserted in said grounded receptacle.

Claim 6

An electrical plug for connecting a three-conductor cord to a grounded electrical receptacle comprising: a body of insulated material attached to said cord; a first and second prong secured in said body and electrically connected to a hot and a neutral conductor of said conductors, respectively; a ground prong in said body and electrically connected to the remaining conductor; and only a single indicator circuit including said prongs and consisting of a resistor in said body electrically connected between said first prong and said ground prong, and an indicator means in said body connected between said second prong and said ground prong for indicating absence of grounding of said remainder conductor when said plug is inserted in said grounded receptacle.

Claim 7

An electrical plug as in claim 4 wherein said indicator means is a light which is ignited to indicate said absence of ground.

Claim 8

An electrical plug as in claim 5 wherein said ground prong is a spring biased automatically retractable prong.

Claim 9

An electrical plug as in claim 4 wherein said indicator means is enclosed by said body and said body has an aperture for exposing a portion of said indicator means.

Claim 10

A lack of ground indicating device comprising: a first prong adapted to be connected to a positive point in an electrical system; a second prong adapted to be connected to a neutral point in said electrical system, said first prong and said second prong being electrically disconnected; a third prong adapted to be connected to a ground point in said electrical system; a resistor connected between said first prong and said third prong; a single indicator means connected between said second prong and said third prong for indicating absence of ground at said third prong when said first and second prongs are connected to said positive and neutral point of said electrical system, respectively.

Claim 11

A lack of ground indicating device comprising: a first prong adapted to be connected to a positive point in an electrical system; a second prong adapted to be connected to a neutral point in said electrical system, said first prong and said second prong being electrically disconnected; a third prong adapted to be connected to a ground point in said electrical system; a resistor connected between said first prong and said third prong; a single indicator means connected between said second prong and said third prong for indicating absence of ground at said third prong when said first and second prongs are connected to said positive and neutral point of said electrical system, respectively.

Claim 12

A device as in claim 8 wherein said indicator means is a visual means which ignites to indicate said absence of ground.

Claim 13

A device as in claim 8 wherein said indicator means is an audible means which is activated to indicate said absence of ground.