Patent ID: 7633302

Claim:
For a cathodic protection rectifier coupled to an underground pipe or storage tank to prevent cathodic erosion thereof, a cathodic protection monitor electrically connected to said cathodic protection rectifier and comprising: a central processing unit (CPU) having an analog-to-digital converter and a memory; first circuit means connected from an output of said cathodic protection rectifier to said CPU to provide a first analog data signal to said analog-to-digital converter thereof which is indicative of the output current of said rectifier; second circuit means connected from the output of said cathodic protection rectifier to said CPU to provide a second analog data signal to said analog-to-digital converter thereof which is indicative of the output voltage of said rectifier; said analog-to-digital converter adapted to digitize said first and second analog data signals for storage in the memory of said CPU; an ISM band antenna adapted to transmit the digitized current and voltage data signals stored in the memory of said CPU in a radiation beam capable of being received by a low flying aircraft or a passing motor vehicle, said digitized current and voltage data signals providing an indication of the effectiveness of the cathodic protection rectifier in preventing cathodic erosion of the underground pipe or storage tank; and an ISM band transceiver located between said ISM band antenna and said CPU and adapted to provide a polling signal that is supplied from the aircraft or motor vehicle to said ISM band antenna by which to cause said CPU to transmit the digitized current and voltage data signals stored therein to the aircraft or motor vehicle by way of said ISM band transceiver and said ISM band antenna.