What are the two types of connections used to interface another machine controller to a PLC?

What are the two types of connections used to interface another machine controller to a PLC?

• A. Serial And USB
• B. Wireless And Ethernet
• C. Direct Connection And Indirect Connection
• D. Analog And Digital

Answer: (C)

When you connect another machine controller to a PLC, you’re looking at how devices exchange data. There are two broad approaches: a direct connection, where the second controller is wired straight to the PLC and communicates without routing through a network, and an indirect connection, where communication goes through a network or gateway. A direct link is common for simple, close-proximity setups and can provide low-latency, straightforward data exchange. An indirect setup uses networked communication (like Ethernet/IP, Modbus, Profibus, etc.) and allows devices to be farther apart or share data through intermediate equipment. Other options describe specific media or signal types rather than the overall connection method, so they don’t fit as the general categories of interfacing two controllers.

When you connect another machine controller to a PLC, you’re looking at how devices exchange data. There are two broad approaches: a direct connection, where the second controller is wired straight to the PLC and communicates without routing through a network, and an indirect connection, where communication goes through a network or gateway. A direct link is common for simple, close-proximity setups and can provide low-latency, straightforward data exchange. An indirect setup uses networked communication (like Ethernet/IP, Modbus, Profibus, etc.) and allows devices to be farther apart or share data through intermediate equipment.

Other options describe specific media or signal types rather than the overall connection method, so they don’t fit as the general categories of interfacing two controllers.