Parameter r9976 (system load; can be found on the CU's drive object) is available in the

system as an online tool. The average value for the computing time load in r9976[1] should

always be below 85.0%. Likewise, the maximum value for the computing time load in

r9976[5] should always be below 85.0%. Exceeding the computing time load limit of 90%

triggers warning A51003. The warning is reset if the computing time load falls below 88%.

The computing time load should not fall below the limit of 85.0% so that the response time of

the STARTER/SCOUT engineering tool is not too greatly restricted.

If the computing time load increases to the point that it is no longer possible for all blocks

and system functions assigned to a sampling time to be completed within this sampling time,

the drive unit switches off and outputs fault F01205: "CU: Time-slice overflow".

Offline mode enables the SIZER engineering tool to make an approximate statement

regarding whether a configuration can be calculated on a CU3x0 or D4xx. The additional

computing time load is not taken into account by activating the DCCs.

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