MC_BR_ParTrace and buffer size

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1

Hello Everyone!

The documentation of Automation Studio 4 doesn’t give any information about the size of the trace buffer size ; I manage to find it out (32768 Bytes, like the standard Trace-buffer tool in AS).

Tracing 4 channels, I meet the problem that my Tracing time isn’t enough (~ 2 seconds when I need ~15), and sample rate needs to stay at its current value ( 400µs)

So here my question: is there any way to increase the buffer size?

Thanks in advance,

Arnaud

2

You could try using the CoTrace library for this, it has a 16 MB raw data limit.

  • The maximum number of samples per trace results from the limitation of the amount of raw data to 16 MB.
  • 12 bytes are used for the timestamp per trace time.
  • A minimum memory of 4 bytes per sample is used depending on the data type of the data point to be traced. LREAL data types require 8 bytes per sample.
  • For example, if exactly one data point of data type BOOL or DINT is traced, then approx. 1000000 samples can be traced.

Automation Help: CoTrace Limitations

3

Hello Tommi,

Thanks a lot for the Quick Reply! I’ll check it out and come back to you regardless of the result!

Arnaud

4

So, I managed to get a 10s trace from a local variable, which is a huge step forward ; but I’m unable to trace an ACOPOS channel in simulation mode.

The function block CoTraceConfigAddDataPoint throws an error -2124414957.

In simulation mode, I’m able to trace the exact channel I’m talking about.

Here is the string parameter I gave to the function Block: ‘*ACP:IF3.ST3_Axis1:111’, which seems to be correct. (111 = ACP10PAR_PCTRL_S_ACT)

Is it not possible to trace an ACOPOS channel in simulation mode?

5

Hi,

the default trace buffer size on all ACOPOS drives is 32768 bytes, see: ParID: TRACE_MAX_DATLEN

On physical drives, i.e. not simulated on PLC or on ArSim, it can be changed.
I changed it on an ACOPOSmulti-3 to its maximum value:

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image1222×292 15.4 KB

This gives us a maximum trace time of ~13s with one 4-byte value and a sampling time of 400µs.

6

Hello Martin,

Thanks for the answer, this is even easier as the previous answer from Tommi (which seems to work) ! I try this in the next days and will mark it as the solution if this works.

I’m just wondering if you have an explanation for the difference in the maximum value between the documentation (32768) and your own experience (131072)? Outdated documentation?