Siemens SIMATIC ET 200SP Manual page 78

Alarms, faults and system events
8.6 Duplicate address detection
Function description
The duplicate address detection function assists you in identifying inadvertent duplicate
addressing.
When commissioning the AS-i system, check that duplicate address detection can be used
for the AS-i configuration used.
● Install the complete AS-i system and ensure that the specified addresses of the slaves
are correct and unique.
● Enable the duplicate address detection function. In firmware V1.1 and higher, you can do
this for AS-i voltages of either 24 V or 30 V.
● Check whether the CM AS-i Master ST signals a duplicate address in spite of correct
slave address assignment. If a duplicate address is signaled on the AS-i master even
though the bus configuration is correct, this means that duplicate address detection
cannot be used for this bus configuration. Should this occur, disable the duplicate
address detection function.
● Note that when the duplicate address detection function is enabled, the presence of a
duplicate address may not be detected, depending on the bus configuration.
Note
The activation status is saved in volatile memory of the AS-i master. After a startup or restart
of the CM AS-i Master ST, duplicate address detection must be activated again via the user
program, if required.
The CM AS-i Master ST signals a detected duplicate address as follows:
● The "CER" LED lights up to indicate a configuration error.
● The "SL_Xy (A)" and "SL_xY (B)" LEDs signal the AS-i address concerned.
● The message "AS-i address used multiple times" is output.
To rectify the fault, check and change the address of the affected AS-i slave, e.g. using the
addressing unit. Via the online function of
AS-i address of an individual slave if there are multiple slaves with the same address on the
AS-i cable.
See also
DS 100 Read setting for duplicate address detection (Page 172)
78
STEP 7
it is not possible to change the
AS-Interface master CM AS-i Master ST (3RK7137-6SA00-0BC1)
Manual, 07/2017, A5E02655262020A/RS-AD/004