Industrial flame sensor communication system

Abstract

A communication and data interpreting system for detecting and converting and combining multiple analog signals from flame detectors into a single analog signal and RS 485 for transmission. This system also uses an analog clamping circuit to generate the analog signal from flame rod sensors and a load resistor and a high voltage generator for generating the signal in an UV sensing tube. The input signals are then multiplexed and sent to a microcomputer. The microcomputer uses a diode and a solid state relay circuit to generate a compatible signal output to a burner control.

What is claimed is:  
     
         1 . A communication system for a plurality of flame sensors in a single or multiple burner system with a connection required between the sensors at a remote location and the burner control or controls, comprising in combination 
 a transmitting module each having an input for connection to a flame sensing transducer exposed to a flame to be sensed, each having an output for producing an electronic level signal indicative of the sensed flame or group of sensed flames;    a receiving module for receiving the information from the transmitting module upon detection of a flame or loss of a flame from a burner or extinguished burner and identifying the identity of the burner or extinguished burner and the time at which the burner is established or extinguished;    a display module with memory means associated with the processor for displaying the signal status of each flame transducer and recording status information at the time of occurrence of loss of signal condition, the status information including the identity of any extinguished burner and the time at which said extinguished burner extinguished.    
     
     
         2 . The combination of  claim 1  wherein the electronic programmable processor includes manually settable means for specifying the number of flame sensors in a particular system.  
     
     
         3 . The combination as set forth in  claim 1  wherein the memory means includes non-volatile memory means for storing status information on the system, the nonvolatile memory means having sufficient capacity to store information on all burners and maintain said storage in the event of power failure upon system shutdown.  
     
     
         4 . The combination as set forth in  claim 1  in which each flame sensor input to the transmitting module includes an output signal at the receiving module associated with a sensing transducer when the sensing transducer detects a flame, the output signal corresponding to the output signal from the sensing transducer and capable of interfacing to the corresponding burner control for the sensing transducer.  
     
     
         5 . The combination as set forth in  claim 1  wherein the memory means includes a plurality of words of storage for storing information regarding system faults as they are detected for later scanning of the stored fault information to detect patterns therein.  
     
     
         6 . The combination as set forth in  claim 1  in which the control system includes a flame watchdog timer triggered by the processor and having an output serving as an enabling signal for fault relay which enables the flame sensing output.  
     
     
         7 . The combination as set forth in  claim 6  in which a flame present signal generated by the transmitting module when polling the flame sensors is operatively associated with the flame watchdog timer to enable the flame watchdog timer to respond to trigger pulses from the processor only in the presence of the flame present signal.  
     
     
         8 . The combination as set forth in  claim 8  wherein the flame watchdog timer has a reset input, and means coupling the reset input to the processor for enabling the flame watchdog timer in a normal mode to sense the flame present signal and provide an output signal to the transmitting module  
     
     
         9 . The combination as set forth in  claim 8  including a further watchdog timer having a trigger input connected to the microcomputer for being serviced periodically within the time constant of the further watchdog timer, an output from the further watchdog timer being connected to a fault relay for control thereof, the output of the watchdog timer serving to energize the fault relay and terminate the flame present signal in the event the further watchdog timer is not triggered by the processor.  
     
     
         10 . The combination as set forth in  claim 1  including an analog-to-digital converter associated with the processor and with the flame sensors, a multiplexer connected to an analog signal from the flame sensors indicative of flame quality, and having an output connected to the analog-to-digital converter for digitizing flame quality signals and passing them to the processor for storage.