Siemens SINUMERIK codes
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Siemens SINUMERIK Controller

Servo/Axis · Intermediate · 30-120 minutes

Alarm 300736

Siemens 300736 - Axis drive Lh characteristic invalid

The value in MD 1143: $MD_LH_CURVE_UPPER_SPEED (LH curve upper speed) is less than or equal to the value in MD 1142: $MD_FIELD_WEAKENING_SPEED (threshold speed for field weakening) or the value in MD 1144: $MD_LH_CURVE_GAIN (LH curve gain) is less than 100 Control reaction: NC not ready. The NC switches to follow-up mode. Channel not ready. NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm.

Siemens SINUMERIKServo/AxisIntermediate30-120 minutes

300736

Siemens 300736 - Axis drive Lh characteristic invalid

Axis drive Lh characteristic invalid

The value in MD 1143: $MD_LH_CURVE_UPPER_SPEED (LH curve upper speed) is less than or equal to the value in MD 1142: $MD_FIELD_WEAKENING_SPEED (threshold speed for field weakening) or the value in MD 1144: $MD_LH_CURVE_GAIN (LH curve gain) is less than 100 Control reaction: NC not ready. The NC switches to follow-up mode. Channel not ready. NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm.

Safety

  • Drive/power/encoder circuit: hazardous voltages may remain in the DC link after power-off. Lock out / tag out, wait for discharge per the drive documentation, and use qualified personnel only.

Common Causes

  • The value in MD 1143: $MD_LH_CURVE_UPPER_SPEED (LH curve upper speed) is less than or equal to the value in MD 1142: $MD_FIELD_WEAKENING_SPEED (threshold speed for field weakening) or the value in MD 1144: $MD_LH_CURVE_GAIN (LH curve gain) is less than 100

Troubleshooting Steps

  1. 1Please inform the authorized personnel/service department.
  2. 2For standard motors: Reset the drive (delete the bootfile) and repeat the startup.
  3. 3For third-party motors: - Modify MD 1143: $MD_LH_CURVE_UPPER_SPEED (Lh curve upper speed) - Modify MD 1144: $MD_LH_CURVE_GAIN (Lh curve gain) - Modify MD 1142: $MD_FIELD_WEAKENING_SPEED (threshold speed for field weakening) should be checked and, if necessary corrected.
  4. 4Switch control OFF - ON. 2-733

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