What does two inputs and two outputs mean for the switch instrument SIO-22 in the Yokogawa DCS?

Personally, I think it’s better to consult the documentation; beginners should read more documents to learn faster

Yokogawa’s help documents contain instructions on using standard blocks, and there is also plenty of information on this topic in forums. It is recommended to look up information on your own, as it helps to gain a good understanding!

Like SIO-22: what does two inputs and two outputs mean? As the name implies, it has two inputs and two outputs; it is a switch valve with two inputs and two outputs. The two inputs represent two feedback signals, while \"open\" and \"close\" are two separate switches, which generally activate in the 1 state ； The same is true for the two outputs; the command signals for open and close are separate from each other. Why is only one output connected to a PIO with two outputs? 1. This output includes both open and close signals; generally, 1 represents open while 0 represents close. 2. If open and close are separate signals, it is sufficient to use just one PIO in the drawing, as long as the two switch signals are adjacent on the IO card. What does SIO-11 one input one output mean? This is similar to the one above: it has both input and output, or it has only input or only output, like SO-2. What is the purpose of this? If it has only an input, it can only be displayed in the DCS; it is only capable of reading feedback signals. For example, SI-2. If it has only an output, it can be operated in the DCS to send command signals. For example, SO-2. I represents an input signal, that is, feedback, while O represents an output signal, that is, a command