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

100 m

Answer

200 m

Answer

1000 m

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 B — unshielded twisted pair, 100 Ω impedance

Answer

Type C — multi-drop coaxial cable

Answer

Type D — fiber optic duplex cable

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

3 repeaters, 3,000 m

Answer

9 repeaters, 9,600 m

Answer

15 repeaters, 15,000 m

Question 4

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

Accepted Answer

32

Answer

16

Answer

64

Answer

126

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

They filter EMI and are placed on every node

Answer

They limit current and are placed only at the master

Answer

They provide pull-up voltage and are placed at any convenient location

Question 6

What is the correct pin assignment for the PROFIBUS DP signal lines on a standard 9-pin D-Sub connector?

Accepted Answer

Pin 3 = RxD/TxD-P (B line), Pin 8 = RxD/TxD-N (A line)

Answer

Pin 2 = RxD/TxD-P (B line), Pin 7 = RxD/TxD-N (A line)

Answer

Pin 4 = RxD/TxD-P (B line), Pin 6 = RxD/TxD-N (A line)

Answer

Pin 1 = RxD/TxD-P (B line), Pin 9 = RxD/TxD-N (A line)