Data logger

The data logger enables the recording of measured values. The recording can be used for the analysis of errors.

Once the recording has been started, it saves all measured values continuously in a ring buffer. The recording stops automatically if a protective function signals an error. With the recorded measured values you can trace the events that led to the error.

Activate control

You have to activate additional process data objects in the process image in order to be able to use the data logger:

  • PDO 0x1610 (Sync Manager SM2 "Outputs")
  • PDO 0x1A10 (Sync Manager SM3 "Inputs")

Proceed as follows:

  • Requirement: an EP9224-0037 is appended in the IO tree in TwinCAT.
1. Double-click on the EP9224-0037 IO module in the IO tree.
2. Click on the Process Data tab.
3. Click on the "Outputs" entry in the Sync Manager field.
4. Activate the PDO Assignment (0x1C12) checkbox next to the entry "0x1610".
  • The process data object "LOG Control" appears in the IO tree.
5. Click on the "Inputs" entry in the Sync Manager field.
6. Activate the PDO Assignment (0x1C13) checkbox next to the entry "„0x1A10".
  • The process data object "LOG Status" appears in the IO tree.
  • Result: The process data objects for controlling the data logger are activated.

Parameterization

The sampling rate for the recording can be selected in the index 8040:11 "Sampling Rate".

Start recording

The output variable "Start Logger" is located in the process data object "LOG Control". The recording is started by a positive edge on this output variable.

If the recording is running, the Status bit
     "LOG Status" > "Status" > "Logger Running"
is set.

Stop recording

The recording stops in two cases:

  • if a protective function signals an error.
  • upon a positive edge on the output variable
         "LOG Control" > "Control" > "Stop Logger".

If the recording has stopped, the input variable
     "LOG Status" > "Status" > "Logger Running"
has the value "0".

Evaluate recorded measured values

The recorded measured values are available as a .csv file. The file must be uploaded from the box to the control computer in order to be able to evaluate it.

Proceed as follows to upload the recorded measured values to the control computer:

1. Double-click on the EP9224-0037 IO module in the IO tree.
2. Click on the Online tab.
3. Click on the Upload button.
  • A dialog box with the title "Save As" appears.
4. Select a directory and write in the field File Name:
     „logdata.csv“
5. Click on the Save button.
  • A dialog box appears with the title "Edit FoE Name".
6. Click OK.
  • The file with the measured values was uploaded to the control computer.

File format

The file with the measured values begins with a header "**** Logfile from Ethercat Slave ****".

Below that follow

  • a file header
  • a measured value table

Format of the file header:

Field

Description

Device Name

Name of the module

File Version

Version number
(Note: when importing from EXCEL the version, e.g. 1.5, is interpreted/displayed as a date (1st May))

Reason for which the snapshot was taken

Reason for stopping the data logger

Age of snapshot

time elapsed from stopping the data logger until the upload

System timestamp (0 if DC not supported)

current timestamp when uploading

Format of the measured value table:

Type

Description

Time offset additional to snapshot age

The age of the measured values in the row in relation to the stopping of the data logger (0 = stop, > 0 older values) in ms

I(U...)

present current values of the channels Us / Up 1 - 4 in 100 mA

Internal Temperature

internal module temperature in °C

Us / Up

Input voltage Us and Up at the 7/8" input in V

Sum Current Us / Up

Sum current of Us and Up in A

I²t(U...)

virtual overload, incremented or decremented depending on the nominal current

  • from 10% warning
  • at 100% shut-off