Which wiring method connects each device directly to the next without using terminal strips?

The correct answer is direct hardwiring because this method involves connecting devices in such a way that each device is linked directly to the next without the use of intermediate components like terminal strips. This approach allows for a straightforward electrical path, reducing potential points of failure. It is commonly used when reliability and minimal complexity are priority considerations, such as in industrial settings where devices need to communicate or operate in close proximity to one another efficiently.

In contrast, options that involve terminal strips, such as PLC wiring or wiring using terminal strips, include intermediary connections that can facilitate easier reconfiguration or troubleshooting but do not represent the direct connection method being described in the question. Similarly, wiring with electric motor drive terminal strips would indicate a setup that includes one or more terminal strips, thereby not fitting the criteria of direct hardwiring either.