CPE CPE Network Topology & Cabling Standards 2

Question 1

What is the maximum segment length for PROFIBUS DP at 12 Mbit/s using Type A cable?

Accepted Answer

100 m

Answer

At the maximum 12 Mbit/s baud rate, the segment length is limited to 100 meters due to signal propagation and timing constraints.

Question 2

Which PROFIBUS topology allows a star wiring arrangement while still maintaining the logical bus structure?

Accepted Answer

Both A and B are correct methods

Answer

Active RS-485 star hubs and optical fiber star couplers both allow physical star wiring while preserving the PROFIBUS logical bus behavior.

Question 3

In PROFIBUS PA cabling, what is the typical supply voltage range provided to field devices over the two-wire MBP bus?

Accepted Answer

9–32 V DC

Answer

PROFIBUS PA (IEC 61158-2 MBP) field devices operate from 9 V to 32 V DC supplied over the same two-wire cable used for communication.

Question 4

What is the maximum current that a single PROFIBUS PA segment power supply can deliver to bus-powered field devices?

Accepted Answer

500 mA

Answer

A standard PROFIBUS PA segment power conditioner typically limits total segment current to 500 mA to protect the bus and support intrinsic safety constraints.

Question 5

What is the maximum segment length for a PROFIBUS PA segment using standard (non-IS) installation?

Accepted Answer

1,900 m

Answer

A PROFIBUS PA segment in standard installation can extend up to 1,900 meters using the recommended cable type with appropriate power supply.

(CPE) Certified Profibus Engineer Practice Test

(CPE) Certified Profibus Engineer Practice Test

CPE CPE Network Topology & Cabling Standards 2