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Entry type: FAQ Entry ID: 19644712, Entry date: 10/12/2004

Technology CPUs: Release from a hardware limit switch

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How can you get an axis back into the working range after it has overrun a hardware limit switch?

When a hardware limit switch is overtraveled, ErrorID 804B or 8013 is displayed in the relevant technology data block and "ErrorStatus.LimitSwitchActive" is set to TRUE. Proceed as follows:

  • Call the MC_Reset with Restart = FALSE; all error messages are retained. 
  • Retract the axis from the hardware limit switch; all error messages are retained even when the axis has left the limit switch. 
  • Call the MC_Reset again with Restart = FALSE; the error messages are acknowledged in the technology data block and "ErrorStatus.LimitSwitchActive" is reset.

More information is available in the manual "S7 Technology", sections 4.5.7 and 4.6.11 "Limits" in Entry ID: 30119663.

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