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Entry type: FAQ Entry ID: 19537149, Entry date: 12/16/2009

How do you read out the operating state and status of an H system?

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Function block "H_STATUS" permits output of the operating modes "RUN/STOP" and the "Master/Reserve" status of an H system.

Overview of functions

  •  Display operating state (RUN/STOP) of the CPU in Rack 0 and Rack 1
  •  Display the status (Master/Reserve) of the CPU in Rack 0 and Rack 1
  •  Report loss of redundancy in the H system

The block is called cyclically in a time interrupt OB (OB 35) and acyclically in the corresponding alarm OBs. The necessary information on system function SFC51 RDSYSST is read out of the system status list (SSL) ID W#16#xy71 and made available at the block outputs. When a CPU of the H system fails, a corresponding message is issued.

More information and details are available in the block description.

Block description:

description_H_STATUS.pdf  ( 34 KB )

Block as library file:

H_STATUS.zip  ( 133 KB )

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