# ID 40016

HLI of MC and PLC has different characteristics.
Description | When the HLI interface is activated by an instance of the FB MCV_HliInterface, the system checks the maximum number of commandable elements such as channels, axes, etc. on the PLC and motion controller sides. The error message is notified if the number of commandable channels or axes, etc. is different on the PLC and motion controller sides.
Response | Class | - | The FB MCV_HliInterface sets its “Error” output to TRUE, waits for a fixed number of cycles and tries to communicate again with the motion controller via the HLI.
Solution | Class | - | At the outputs “ExpectedHli” and “ActualHli” of the FB instance of type MCV_HliInterface, the maximum number of channels, axes, etc. can be checked by the variable …Max. The output “ExpectedHli” displays the maximum number of the PLC’s HLI interface and the output “ActualHli” display the maximum number of the motion controller’s HLI interface.

If there are different values for 2 variables with the same name, check the version identifier of the HLI interface on the PLC and motion controller sides by comparing the variable versionString of both outputs.

Then check whether a motion controller with the wrong version identifier was started or whether the PLC application included an HLI library with the wrong version identifier. In the first case please start the motion controller with the correct version identifier; in the second case please include the HLI library with the correct version identifier in the PLC application.

If none of the above causes exists, contact the controller supplier and specify the version identifier at the outputs "ExpectedHli" and "ActualHli".

Error type | -

## Notice

Only the first 12 characters of the version identifier are checked and if they are equal that’s sufficient consistence of the HLI interface at PLC and motion controller to interact together.