Siemens ET 200SP - Component Installation Let’s examine how to install each component of this ET 200sp remote I/O on the din rail. With the rail in place, you put the head module on the rail. The same goes for the base unit. You need to install a terminator or what siemens calls a server module. The same way you install the base modules. Watch the video and answer the question. What is the name of the component that the I/O modules are plugged in to? ▶ Order ET 200SP Base Unit now https://bit.ly