CPE Communication Protocols & Standards 5

Question 1

What distinguishes PROFIBUS FMS from PROFIBUS DP in terms of application use case?

Accepted Answer

FMS targets cell-level peer-to-peer communication with complex data objects; DP targets fast I/O at field level

Answer

PROFIBUS FMS (Fieldbus Message Specification) was designed for supervisory-level communication with complex data models, while DP is optimized for fast cyclic I/O with field devices.

Question 2

Which IEC 61784 profile family specifically covers PROFIBUS communication profiles?

Accepted Answer

CP 3/x (Communication Profile Family 3)

Answer

IEC 61784 Communication Profile Family 3 (CPF 3) defines the PROFIBUS DP and PA communication profiles.

Question 3

In PROFIBUS DP, what happens when two masters have the same station address configured?

Accepted Answer

Both masters will fail to join the logical token ring, causing bus disruption

Answer

Duplicate master addresses cause token ring initialization failures and can disrupt all communication on the bus segment.

Question 4

What is the data transfer rate used by PROFIBUS PA on its MBP physical layer?

Accepted Answer

31.25 kbps

Answer

PROFIBUS PA operates at a fixed 31.25 kbps on the Manchester-coded, bus-powered (MBP) physical layer.

Question 5

Which PROFIBUS extension standard addresses functional safety up to SIL 3?

Accepted Answer

PROFIsafe

Answer

PROFIsafe is the PROFIBUS (and PROFINET) safety communication profile certified for use in applications requiring up to SIL 3 per IEC 61508.

(CPE) Certified Profibus Engineer Practice Test

(CPE) Certified Profibus Engineer Practice Test

CPE Communication Protocols & Standards 5