Signal discriminating system

Claim 2

Apparatus for remotely monitering at least one consumer load sensing means connected to low voltage commercial power distribution lines for measuring a load connected across said distribution lines, comprising: injecting means for injecting a high frequency signal having at least one frequency component into said distribution lines, wherein the portion of said high frequency signal alloted to a given consumer has a reference signal portion and a measuring signal portion; flow path circuit means providing a signal flow path for said reference signal portion; switching means for selectively connecting said flow path circuit means across said distribution lines in parallel with said load; load sensing means operative in response to the state of said load to create a flow path for said measuring signal portion through one of said flow path circuit means and said load, depending upon the state of said load; detector means for detecting said reference signal portion and said measuring signal portion; and comparing means for comparing the levels of the detected reference and measuring signal portions to obtain information relating to the state of said load.

Claim 3

Apparatus as defined in claim 1, wherein said high frequency signal comprises one frequency component; and said flow path circuit means comprises a series resonant circuit tuned to said high frequency signal.

Claim 4

Apparatus as defined in claim 1, wherein said high frequency signal comprises first and second frequency components to be concurrently injected serving as said reference signal portion and said measuring signal portion, respectively; and said flow path circuit means comprises first and second series resonant circuit means tuned to said first and second frequency components, respectively.

Claim 5

A system as defined in claim 1, wherein said load sensing means comprises a watt-hour meter, and said means operative in response to the state of said device comprises a switch contact which operates once for each time said watt-hour meter reads a predetermined amount of power consumption in said load.

Claim 6

Apparatus as defined in claim 1, wherein: said high frequency signal comprises: a starting signal portion for putting a second load into a controllable condition, first and second command signal portions for controlling said second load, a second reference signal portion, and a second measuring signal portion; and the apparatus further comprises: starting means responsive to said starting signal portion of said high frequency signal for initiating the control operation of said second load; first control circuit means responsive to said first command signal portion of said high frequency signal for generating a first control signal; second control circuit means responsive to said second command signal portion of said high frequency signal for generating a second control signal; further switching means for selectively connecting said first and second control circuit means in parallel with said starting means; and relay means connected to the outputs of said first and second control circuit means for connecting said second load and said flow path circuit means to said distribution lines, wherein said relay means connects said second load and said flow path circuit means to said distribution lines in response to said first control signal and disconnects said second load and said flow path circuit means from said distribution lines in response to said second control signal and wherein said flow path circuit means provides a signal flow path for said second reference signal portion; wherein said detecting means and said comparing means respectively detect and compare said second reference and measuring signal portions in the same manner as the first reference and measuring signal portions.