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A.1.5 functions – Siemens SIMATIC NET PROFIBUS User Manual

Page 244

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Testing PROFIBUS

A-4

PROFIBUS Networks SIMATIC NET

6GK1970-5CA20-0AA1 Release 2 05/2000

A.1.5

Functions

Checking the PROFIBUS Cable

In this test, the PROFIBUS cable alone is tested. The following errors can be
detected:

S

Short-circuit between data lines or between data line and shield

S

Line break

S

Shield break

S

Reversed polarity (A and B)

S

Reflections that could cause errors

S

Check of the number of activated terminating resistors

The length of the PROFIBUS cable can also be measured.

Checking the RS-485 Interface of a Slave

The test device is connected to one slave. This is supplied with power. The device
then makes the following measurements:

S

RS-485 driver OK/defective

S

Power supply to the terminating resistor OK/not OK

S

RTS signal present/not present

Checking the Accessibility of Nodes

S

List of accessible slaves (live list)

S

Addressing of specific slaves