Is there any difference between 505 overspeed ejection and 203 overspeed ejection?
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Is there any difference in their mechanism of exiting the vehicle? Where is the signal sent from, where is it received, and where is the ejection action carried out? Thank you
505 refers to trip due to a 2-out-of-2 interlock, while 203 refers to trip due to a 3-out-of-2 interlock; the trip speed for the latter is higher than that for the former. Speed sensors are installed on the signal discs of the turbine’s front bearings, with a total of 6 or 7 such sensors in general. Two go to 505, three go to 203, one is displayed on-site, and one is displayed on DCS. The mechanism for shutdown is the same: once the shutdown speed is reached, a shutdown signal is generated, after which the solenoid valve of the quick-shut valve loses power, the oil supply to it is cut off, and the quick-shut valve closes. This is internal interlock logic; it may be related to ESD.