摘要:
A system for interconnecting a plurality of fuel burners (14-17) utilizes program modules (30-33) at each of the burners. The program modules contain microcomputers (86) and are interconnected with a communications module (41) by a first level data bus (40-43). This interconnection and the programming of the modules prevents cross talk between the units. The communications module further is connected to a second level data bus (70), that provides auxiliary functions without interaction with the data contained on the first data buses. The information supplied to the second data bus is limited so that no safety related function can be affected.
摘要:
An automatic firing rate controller (55) uses proportional control squared, an integration which reflects the past load history to determine the present load, and further has a function term which relates the rate of change of pressure with respect to time in order to make more responsive the normal load control operation. The system is also capable of on-off control that will hold the system in low fire to allow for stabilization, and to avoid thermal shock to a boiler (Fig. 3).
摘要:
Sensing the operating condition of a burner system relies on flue temperature as the indicating variable. When the operating status is stable, the flue temperature should be nearly identical to that when the system was known to be in proper condition. During a time when the system is known to be in proper operating condition, the flue temperature is recorded during stable operation for a number of different firing rates. When identical or similar firing rates occur at a later time and operation is stable, the operating flue temperature is compared with the current flue temperature, and if substantially different, an operation status signal is set to a state indicating this change in operating condition.
摘要:
A system for interconnecting a plurality of fuel burners (14-17) utilizes program modules (30-33) at each of the burners. The program modules contain microcomputers (86) and are interconnected with a communications module (41) by a first level data bus (40-43). This interconnection and the programming of the modules prevents cross talk between the units. The communications module further is connected to a second level data bus (70), that provides auxiliary functions without interaction with the data contained on the first data buses. The information supplied to the second data bus is limited so that no safety related function can be affected.
摘要:
A heating plant (11) has a fuel burner (12) operated by a fuel burner control system that utilizes a program module including a microcomputer (51), memory (52), analog-to-digital converters (54-55), and sensor monitoring arrangements (53) to track the status of analog sensors. This system insures that the sensors are not open circuited or short circuited. This system can be provided with a keyboard and display unit (15) having continuous output information on the status of temperature, pressure, and flame current.
摘要:
The water level in a boiler 9 is monitored by a probe 15 driven by an AC source 11. If the water is high, the water resistance Rw completes a first current path i1 which charges C1 via D1 on alternate half-cycles and alternately charges and discharges C2 on successive half-cycles. C1 then transfers its charge through R2 to C3 via path i2, which has a long time constant (20 sl. When C3 is charged, amplifier A1 energizes relay RL1, which closes contacts RL1/1, so modifying the characteristics of current loop i2, and closes contacts RL1/2, closing fuel valve 44 and allowing boiler 9 to be heated. If the water level falls, charging of C1 via loop i1 ceases: charging of C3 via the loop i2 (which now has R2 shunted out) ceases; and C2 discharges through D2 and R4 via loop i3. When the voltage on C3 falls enough, amplifier A1 output changes, de-energizing relay RL1, so opening contacts RL1/2 and turning off the boiler flame, and also opening contacts RL1/1 and so re-establishing the original characteristics of C3 charging current loop i2.
摘要:
A heating plant (11) has a fuel burner (12) operated by a fuel burner control system that utilizes a program module including a microcomputer (51), memory (52), analog-to-digital converters (54-55), and sensor monitoring arrangements (53) to track the status of analog sensors. This system insures that the sensors are not open circuited or short circuited. This system can be provided with a keyboard and display unit (15) having continuous output information on the status of temperature, pressure, and flame current.
摘要:
A boiler control utilizing a pressure sensor (35, 36) is provided that operates the system in the low fire mode if the load is light, and can be satisfied in that mode. If the low fire operation is inadequate to hold the load and the pressure drops, the boiler (24) is then operated in a modulating mode which includes a high fire iimit. This is accomplished by sensing the variation of a pressure responsive means (22) and by providing a burner control system (23) that monitors that pressure responsive means