CCST CCST Communications & Networking in Control Systems 2

Question 1

Which Foundation Fieldbus segment type operates at 31.25 kbit/s and is intrinsically safe for use in hazardous areas?

Accepted Answer

FF H1

Answer

Foundation Fieldbus H1 operates at 31.25 kbit/s and can be powered intrinsically safely, making it suitable for Zone 0/1 hazardous locations.

Question 2

In Modbus RTU communication, what is the function of the CRC (Cyclic Redundancy Check) appended to each message frame?

Accepted Answer

Detecting transmission errors in the data frame

Answer

The CRC in Modbus RTU is a 16-bit error-detection code that allows the receiver to identify corrupted data frames.

Question 3

What is the role of a Device Type Manager (DTM) in an FDT/DTM framework used in modern field device management?

Accepted Answer

It provides a device-specific software component for configuration and diagnostics within an FDT frame application

Answer

A DTM is a device-specific software plug-in that runs inside an FDT Frame application to provide full configuration, calibration, and diagnostic access to a field instrument.

Question 4

When configuring a Modbus TCP/IP connection, which default TCP port number is used?

Accepted Answer

502

Answer

Modbus TCP/IP uses TCP port 502 as its standard registered port for communication between master and slave devices.

Question 5

Which industrial protocol is specifically designed for time-sensitive applications and uses IEEE 802.1AS for clock synchronization?

Accepted Answer

PROFINET IRT

Answer

PROFINET IRT (Isochronous Real-Time) uses IEEE 802.1AS Precision Time Protocol for sub-microsecond clock synchronization to meet strict motion control timing requirements.

(CCST) Certified Control Systems Technician Practice Test

(CCST) Certified Control Systems Technician Practice Test

CCST CCST Communications & Networking in Control Systems 2