CyberCertPrepOT Security FundamentalsOT Fundamentals: Network Architecture & ProtocolsEASYFree question
A technician traces cabling for a Modbus RTU loop and finds a twisted pair running between 12 controllers. Which electrical interface is most likely in use?
- A.RS-485 with multidrop twisted pair wiring
- B.RS-232 with a point to point serial cable link
- C.100BASE-TX with star topology copper cabling
- D.4-20 mA with a dedicated loop per field device
Why A is correct
RS-485 supports multidrop twisted pair buses with many nodes over long runs, which fits a loop serving 12 controllers. RS-232 is point to point, 100BASE-TX is Ethernet, and 4-20 mA is an analog signal.
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