摘要 |
A temperature control system and method for controlling the bus bar temperature of an automated guideway transit system in relation to the ambient dew point temperature. A resistance temperature device detects the temperature of the bus bars, and a dew point cell detects the dew point temperature of the ambient atmosphere. A first transmitter converts the detected bus bar temperature to a first electrical signal, and then amplifies and transmits the first electrical signal. A second transmitter converts the detected dew point temperature to a second electrical signal, and then amplifies and transmits the second electrical signal. A first electronic comparator receives the transmitted signals and detects the magnitude of the difference between the two signals. When the magnitude of the difference between the two signals reaches a set level, an output signal is triggered. A second electronic comparator generates an output signal whenever the detected bus bar temperature is less than or equal to a preset value (approximately 32 DEG F. (0 DEG C.)). The outputs from the two comparators are used to trigger an AND gate, which in turn energizes a relay used to turn on a heating element, thus keeping the bus bar temperature within a set range of the ambient dew point temperature.
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