Cause : Configuration telegram error comes when the PROFIBUS master attempts to establish a connection using an incorrect configuring telegram.

Alarm value (r2124, interpret decimal):
2: Too many PZD data words for input or output. The number of possible PZD is specified by the number of indices in r2050/p2051.
3: Uneven number of bytes for input or output.
211: Unknown parameterizing block.
501: PROFIsafe parameter error (e.g. F_dest).
502: PROFIsafe telegram does not match.

Check the bus configuration on the master and slave sides.
Re alarm value = 2:
Check the number of data words for input and output.
Re alarm value = 211:
Ensure offline version <= online version.
Re alarm value = 501:
Check the set PROFIsafe address (p9610).
Re alarm value = 502:
Check the enable of F-DI (p9501.30)