US 5,293,115 A · Method and system for sensing removal of a utility meter from its socket

Abstract

A method and system is disclosed for indication and prevention of tampering with an electricity meter having control circuitry for automatic remote reading. The control circuitry, provided externally of the meter in a base or base extension, to which the meter is connected, is also used for tamper detection. Embodiments of the invention include use of optical sensing, voltage detection and proximity detection. Ambient light sensing may be performed to detect separation of the meter from the external receptacle. Reflected light to a reflective surface of the meter is sensed to determine if the meter is properly engaged. Presence of a meter connection plug element may be sensed either optically or by position responsive switch. Voltage of the utility supply and meter user output may be monitored to determine tampering.

Claims7

Dependent claims

A method for ascertaining tampering of a connection between an electricity meter, of the type which includes plug extensions which plug into respective sockets in a base external to said meter, and an external base to which said electricity meter is connected and through which external power is supplied to said meter comprising the steps of:

(a) emitting light pulses from said external base;
(b) sensing light reflected by said meter by circuitry solely within said external base;
(c) generating a bilevel voltage by said circuitry within said external base, each level corresponding respectively to a relatively bright light condition and a relatively dark condition;
and
(d) detecting a meter tampering condition in response to said bilevel voltage.

2 more elements

A device for detecting tampering of a connection between an electricity meter, of the type which includes plug extensions which plug into respective sockets in a base external to said meter, and an external base to which said electricity meter is plugged and through which external power is supplied to said meter, said device comprising:

(a) passive means which is part of said meter which can modify a signal from a source external to said meter;
(b) active means, contained solely within said external base, said active means not being a part of said meter or needing any physical connection to said meter apart from plugging said meter into said external base, said active means providing a signal to said passive means;
and
(c) detecting means, contained solely within said external base for indicating the proximity of said meter to said external base and for thereby detecting that said meter has been unplugged from said external base, whereby a tampering condition will be indicated.

1 more element

Dependencies are inferred from the claim text.

Method and system for sensing removal of a utility meter from its socket

Life of this patent

Method and system for sensing removal of a utility meter from its socket

Life of this patent

Abstract

Claims7