CPE CPE Network Topology & Cabling Standards

Question 1

What is the maximum segment length for PROFIBUS DP operating at 1.5 Mbit/s using Type A cable?

Accepted Answer

400 m

Answer

At 1.5 Mbit/s, PROFIBUS DP Type A cable supports a maximum segment length of 400 meters before a repeater is required.

Question 2

Which cable type is the recommended standard cable for PROFIBUS DP installations per IEC 61158?

Accepted Answer

Type A — shielded twisted pair, 135–165 Ω impedance

Answer

Type A cable (shielded twisted pair with 135–165 Ω characteristic impedance, ≤30 pF/m capacitance) is the IEC 61158 standard recommendation for PROFIBUS DP.

Question 3

How many repeaters can be cascaded in a PROFIBUS DP network, and what is the resulting maximum network span at 93.75 kbit/s?

Accepted Answer

9 repeaters, 10,000 m

Answer

Up to 9 repeaters can be cascaded, and at 93.75 kbit/s (segment length 1,200 m) the total network span can reach approximately 10,000 meters.

Question 4

What is the maximum number of stations (nodes) per PROFIBUS DP segment including the master?

Accepted Answer

32

Answer

Each PROFIBUS DP segment supports a maximum of 32 stations (addresses 0–31), including masters and slaves.

Question 5

In a PROFIBUS DP network, what is the function of bus termination resistors and where must they be placed?

Accepted Answer

They match cable impedance to prevent signal reflections and must be placed at both ends of each segment

Answer

Termination resistors match the cable's characteristic impedance to absorb signal energy at each segment end, preventing reflections that cause communication errors.

(CPE) Certified Profibus Engineer Practice Test

(CPE) Certified Profibus Engineer Practice Test

CPE CPE Network Topology & Cabling Standards