According to the thin film type LNG ship dangerous area instrument power supply
cut-off
system, after an LNG ship IAS
system is powered on and started, all
signal channels of modules in a
signal acquisition cabinet are in an electrified (active) state, and the single channel cannot be
cut off in a
remote control mode. In order to ensure that related signals can be accurately isolated, an independent
signal acquisition
system needs to be additionally arranged on the basis of the existing power supply and communication architecture of the IAS system, and the independent
signal acquisition system is used for monitoring in a specific area and
cutting off an instrument signal (an instrument power supply). When a
combustible gas alarm occurs in an area, the independent
signal acquisition system is
cut off, so that the system is in a power-off (passive) state. Therefore, all signals accessed to the acquisition cabinet in a specific area are ensured to be in a power-off (passive) state, and the purpose of
intrinsic safety is achieved.