axismd.ai
Siemens SINUMERIK Controller
Servo/Axis · Intermediate · 30-120 minutes
Siemens 300751 - Axis drive speed control gain too high
This alarm occurs when the speed control gain (MD 1407 or MD 1408) is set too high, causing instability in the axis drive. Reduce the gain values to resolve the issue.
300751
Siemens 300751 - Axis drive speed control gain too high
Axis drive speed control gain too high
The proportional gain of the speed controller MD 1407: $MD_SPEEDCTRL_GAIN_1 (P gain of speed controller) or MD 1408: $MD_SPEEDCTRL_GAIN_2 (P gain of upper adaption speed) has been set too high Control reaction: NC not ready. The NC switches to follow-up mode. Channel not ready. NC Start disable in this channel. Interface signals are set. Alarm display. NC Stop on alarm. Channel not ready.
Root Cause Summary
This alarm occurs when the speed control gain (MD 1407 or MD 1408) is set too high, causing instability in the axis drive. Reduce the gain values to resolve the issue.
Safety
- Drive/power/encoder circuit: hazardous voltages may remain in the DC link after power-off. Lock out / tag out, wait for discharge per the drive documentation, and use qualified personnel only.
Causes and Fixes
- 1
Access machine data
Navigate to MD 1407 ($MD_SPEEDCTRL_GAIN_1) and MD 1408 ($MD_SPEEDCTRL_GAIN_2) in the control parameters.
- 2
Reduce gain values
Lower the gain settings incrementally (e.g., reduce by 10-20%) to stabilize the system.
- 3
Test and restart
Clear the alarm, test the axis movement, and restart the program.
Call a technician if:
- ·If reducing gain does not resolve the issue
- ·If axis behavior remains unstable after adjustments
Prevention
- Validate gain settings during commissioning with qualified personnel
- Document stable gain values for future reference
- Regular parameter backup and verification
- Only allow trained personnel to modify drive parameters
Common Mistakes
- Overlooking related machine data parameters
- Setting gain values without testing incrementally
Seeing Multiple Alarms?
Seeing another alarm with this one? Enter the code.
Get machine-aware diagnosis
AxisMD logs alarms against your actual machines, tracks patterns, and gives AI context your manual doesn't have.
Start freeWas this guide helpful?
Always verify with your machine manual or a certified technician before performing service procedures.