Ngọn lửa bảo vệ kiểm soát tiểu học. là trái tim của bu flll 'kiểm soát! ~. Nó lrans / ale đầu vào 1rom ngọn lửa delector, điều khiển, và giới hạn vào trình tự kiểm soát 01 molor burner, ignilion, thí điểm, và van nhiên liệu chính. Chính ", ontrolfunclions được tóm tắt trong Hình 1. | PR I MARY CONTROLS HONEYWELL FLAME SAFEGUARD PRIMARY CONTROLS The Flame Safeguard Primary Control 18 the heart of the burner control system. It translates inputs from the flame detector controller and limits into sequenced control of the burner motor ignition pilot and main fuel valve. Primary-control functions are summarized in Fig 1. PRIMARY CONTROL FUNCTIONS IWPUTS OUTPUTS CONTROLLER LIMITS FLAME signal I F5G k PRIMART CONTROL I __ BURNER MOTOR IGNITION PILOT VALVE MAIN VALVE S The complete Flame Safeguard Primary Control performs 3 principal functions. First It sequences the operation start run and shutdown of the burner system. A timer may be added to the primary control to add a timing capability to the sequencing function of the device and in this case the primary control is known as a programmer. Second the primary control supervises the presence of a flame cutting off the fuel supply If flame Is not present. Third the primary control checks Itself against unsafe failure. Typically the control performs e safe start check or checks for a flame-simulating failure before startup. If Such a condition is present the burner canned start. In addition most primaries also check the continuity of their safety Switch circuitry. The ultimate in self-checking ability Is the Honeywell Dynamic Saif Check system which checks its internal circuitry about 1 to 4 times each second during operation. FIG. 1 -FUNCTIONS OF A PRIMARY CONTROL R7023 FLAME DETECTOR RELAY----------------- The simplest device in the FSG famlty of electronic control relays is the R7023. This control is not a primary control. It does not have any sequencing or programming ability. Its relay pulls in when flame is sensed and drops out on loss of flame so it must be used with other equipment if a complete flame safeguard application is to be made. The R7023 Is available In 2 models the R7Ữ23B and the R7Ũ23C. The B model has an electronic circuit for use with rectification type flame detectors. .
