Before disassembling or connecting this device, the field power supply (either via the field terminal or via the carrier bus) must be disconnected. It is strictly forbidden to plug and unplug the equipment in the state of system power-on. For non-spark field circuits, the power supply must be cut off prior to mating, including fused terminal blocks. The product adopts a rotary positioning system to ensure the compatibility of the I/O card and the terminal block after installation, and ensure that the positioning key of the terminal block matches the matching I/O card when using.