Does turbine 505 show that two speed signals have disappeared?
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The turbine drives the compressor to operate; an alarm is triggered due to low high-pressure oil pressure from the oil pump, causing the unit to shut down. The auxiliary oil pump starts automatically, and a few seconds later the unit shuts down again. The initial shutdown indication shows a 505 interlock shutdown, with 505 indicating that two speed signals have disappeared. Could fellow sailors help analyze the reason?
There might be interruptions in the speed signal; we have encountered this issue as well. However, it doesn’t cause the machine to stop operating – instead, there is an incorrect display. The speed fluctuates by up to 500 revolutions per minute, and the stroke of the hydraulic actuator fluctuates by 6–7 mm; beyond that, the machine shuts down due to overspeed.
Does the low high-pressure oil interlock cause the governor to fail? Why has the speed signal disappeared?