Voltage indicating test point cap
AssigneeE. O. Schweitzer Manufacturing Co., Inc.
InventorEdmund O. Schweitzer, Jr.
Life of this patent
Estimating the term…
Abstract
A test point cap provides a visual indication of the voltage level of an alternating current in the conductor of a connector on which the cap is installed. The test point cap includes a bridge-type rectifier circuit which is capacitively coupled to the conductor through a test point terminal on the connector. The rectifier circuit charges a capacitor across which a neon lamp visible through a window in the end of the cap is connected, the rate at which the neon lamp flashes providing an indication of the voltage level on the conductor.
Claims7
A voltage-indicating test point cap for mounting to the test point terminal of a connector employed in a high-voltage system wherein the connector includes a conductor embedded in an insulating member encased in a conductive sheath referenced to ground, and wherein the test point terminal includes a projection of the insulating member extending through the conductive sheath and having an electrically conductive test point contact embedded in the insulating member, the test point contact having an exposed portion at the outer end of the test point terminal, alternating current in the conductor capacitively inducing a proportional alternating current at the test point contact, said voltage-indicating test point cap comprising, in combination:
- circuit means including a rectifier having input terminals and output terminals;
- said circuit means including a capacitor coupled across said output terminals, and a light-emitting voltage discharge device coupled across said capacitor;
- means including an electrically conductive outer shell having an open end for mounting to said test point terminal and a closed end, and a window, said outer shell contacting said grounded connector sheath when said test point cap is mounted on said test point terminal;
- a cylindrical housing telescopingly disposed within said outer shell, at least the portion of said housing adjacent said window being transparent;
- said light-emitting discharge device being located within said cylindrical housing in substantial alignment with said window;
- an electrically conductive spring contact disposed within said cylindrical housing, said spring contact having one end connected to one of said input terminals of said rectifier and its other end disposed for engaging said exposed portion of said test point contact;
- the other one of said input terminals of said rectifier being coupled to said outer shell to reference said rectifier to ground,
- said induced current being coupled to said rectifier by said contact and rectified by said rectifier to charge said capacitor, said discharge device emitting a flash of light through said window upon said capacitor charging to the flash potential of said discharge device, the rate of said flashes being proportional to the voltage level of the alternating current applied to said conductor.
Dependencies are inferred from the claim text.