What does the parameter “Slave Telegrams Without Master Call” mean? This parameter is found on the Advanced Statistics tab on the Online Statistics window of the Siemens As-i network analyzer.

Hi io_learner
As advised, this is a UK forum for UK support, you should be consulting your software and hardware supplier.

However one of our members has advised this comment:-
This is a rare case and have only seen it once. EMC can cause the slave to send a telegramme without a call from the master. This means that within the process image of a PLC you will see bits going from 0 to 1 on the input image. The master will go into error due to the Manchester II coding and the analyser can identify which node is at fault.

Further questions please place any further questions in your own country. These resources are managed for the UK membership the UK only.

Dear io_learner,

because of noise in your AS-i line it can happen that the AS-i Analyser does not recognize the request from the master, but it recognizes the slave response. This depends on where in your network is the Analyser mounted.

This error is not as significant as the telegram repetitions from the slaves.

Kind Regards

Derek Lane - 20 February 2009 04:07 PM

Hi io_learner
As advised, this is a UK forum for UK support, you should be consulting your software and hardware supplier.

However one of our members has advised this comment:-
This is a rare case and have only seen it once. EMC can cause the slave to send a telegramme without a call from the master. This means that within the process image of a PLC you will see bits going from 0 to 1 on the input image. The master will go into error due to the Manchester II coding and the analyser can identify which node is at fault.

Further questions please place any further questions in your own country. These resources are managed for the UK membership the UK only.

Very well explained. Got ideas from it..
Regards,
sallyhawks