Remote supervisory monitoring and control system

Claim 1

Apparatus which monitors and controls equipment at a remote site, said apparatus comprising:: monitorinq means for sensing conditions at a plurality of monitored points in equipment at a remote site and for producing data signals representing the sensed conditions; programmable microprocessor means for controlling the operations of said apparatus in an operator-controlled mode and in an automatic mode, for receiving and storing data signals of said monitoring means, for producing alarm signals representing alarm conditions when the data signals of said monitoring means reach predetermimed values, and having output ports connected to circuits for controlling output parameters and carrying out equipment control functions to correct the alarm conditions; transmitting means coupled to a public telephone net-work for producing and transmitting thereover a predetermined sequence of dual tone multi-frequency (DTMF) signals responsive to receipt of an alarm signal from said microprocessor means; voice synthesizer means operable responsive to the alarm signal and an off hook condition of a telephone connected to the public telephone network for producing and transmitting over the telephone network an oral announcement of an alarm condition corresponding with an alarm signal; receiving means for receiving DTMF signals produced by an operator of the off hook telephone, said apparatus having multiple privilege levels including an operator privilege level established when DTMF siqnals coupled though said receiving means are in the form of a prescribed operator privilege code and a programmer privilege level established when DMTF signals coupled through said receiving means are in the form of a prescribed programmer privilege code, and said apparatus having a different response to received DTMF siqnals depending on which privilege level is established in the apparatus; said microprocessor means includinq means for communicating data signals and alarm signals to said voice synthesizer means, said voice synthesizer means, responsive thereto, producing and transmittinq over the public telephone network to an operator of the off hook telephone an oral announcement of the sensed equipment conditions including status reports of predetermined sensors and alarm conditions; said microprocessor means including means, operable when said apparatus is in the operator-controlled mode and after the operator privilege level has been established, for receivinq subsequently transmitted DTMF signals representing desired states of said output ports of said microprocessor means and circuits connected thereto, and for setting said output ports of said microprocessor means and circuits connected thereto in the desired states to control output parameters and carry out equipment control functions in accordance with the contents of the subsequently transmitted DTMF signals; programmable memory means in said microprocessor means for storing instructions and parameters for operation of said microprocessor means in both the operator-controlled mode and the automatic mode, instructions stored in said memory means comprising programs used by said microprocessor means in both the operator-controlled mode and the automatic mode to monitor the status of equipment at the site, to detect alarm conditions based upon a comparison of the data signals produced by said monitoring means with the predetermined values, the predetermined values comprising input parameters stored in said memory means, and to generate alarm signals if the comparison detects alarm conditions; instructions stored in said memory means also comprising programs used by said microprocessor means in the operator-controlled mode to set said output ports to control output parameters and carry out equipment control functions responsive to DTMF signals produced by the operator of the off hook telephone; instructions in said memory means also comprising programs used by said microprocessor means in the automatic mode without operator intervention to set said output ports to control output parameters and carry out equipment control functions responsive to an alarm condition; said microprocessor means including means operable after a programmer privilege level is established in said apparatus, for receiving subsequently transmitted DTMF signals to set said apparatus in either the automatic or operator-controlled modes and, when representing modifications to or changes in instructions and input and output parameters including privilege level codes, to reprogram said memory means in accordance with the contents of the last-mentioned subsequently transmitted DTMF signals.