The FANUC SV0422 alarm indicates a torque control overspeed condition. This alarm occurs when the allowable speed specified in torque control has been exceeded.
In torque control mode, the CNC system controls the servo axis according to a torque command while also monitoring the allowed speed limit. If the actual or commanded operating condition exceeds the specified allowable speed in torque control, the system may generate the SV0422 alarm.
This alarm is mainly related to the torque control command, torque setting value, speed limit value, torque control parameters, and the logic of the torque control program.
Quick Summary of FANUC SV0422 Alarm
| Alarm Code | SV0422 |
|---|---|
| Alarm Meaning | Torque Control Overspeed |
| Main Cause | The allowable speed specified in torque control has been exceeded. |
| Control Mode | Torque control |
| Key Check Items | Torque setting value, speed limit value, torque control parameters, program speed setting, torque control program logic |
What Does FANUC SV0422 Alarm Mean?
SV0422: Torque Control Overspeed
The FANUC SV0422 alarm means that the speed allowed under torque control has been exceeded. During torque control, the system does not only monitor the torque command; it also checks whether the speed remains within the specified allowable range.
If the torque control command, speed limit value, or program logic causes the axis to exceed the permitted speed, the CNC system will detect this condition and issue the SV0422 alarm.
Common Causes of FANUC SV0422 Alarm
The most common causes of FANUC SV0422 torque control overspeed alarm include:
1. Speed Limit Value in Torque Control Is Too Low or Not Suitable
The speed limit value specified in torque control may not be suitable for the actual machine condition or program requirement.
If the allowed speed limit is set too low, the machine may easily exceed the permitted range during torque control and trigger the SV0422 alarm.
2. Torque Setting Value Is Not Suitable
If the torque setting value in the torque control command is too high or not suitable for the machine condition, the axis may accelerate or move beyond the allowed speed range.
In this case, the torque setting value and speed limit value should be checked together because the two settings affect how the axis behaves in torque control mode.
3. Torque Control Parameters Are Not Set Correctly
Incorrect torque control-related parameters may cause the CNC system to apply torque control in an unsuitable way.
If the speed limit control parameters or related torque control parameters are not reasonable, the alarm may occur even when the program appears correct.
4. Programmed Speed in Torque Control Is Not Reasonable
The torque control program may include a speed condition that is not suitable for the actual machine operation.
If the programmed speed or torque control instruction allows the axis to exceed the specified speed limit, the SV0422 alarm may occur.
5. Torque Control Program Logic Is Not Suitable
The logic of the torque control program should be checked carefully. If the program does not correctly limit the speed, transition between modes, or control the torque command, the system may detect overspeed during torque control.
This is especially important when torque control is used in special applications or combined with other CNC functions.
How to Troubleshoot FANUC SV0422 Alarm
When troubleshooting the FANUC SV0422 alarm, the key point is to confirm why the allowable speed in torque control has been exceeded.
You may need to check:
- Whether the alarm occurs during torque control operation
- Whether the torque setting value in the torque control command is suitable
- Whether the speed limit value in torque control is set correctly
- Whether the speed limit control parameters are reasonable
- Whether related torque control parameters match the machine condition
- Whether the torque control program speed setting is suitable
- Whether the torque control program logic is correct
- Whether the alarm appeared after parameter changes, program changes, or machine function modification
Because SV0422 is directly related to torque control speed limits, it is important to check both the parameter settings and the actual program logic. Simply increasing the speed limit without confirming the torque command and machine condition may create additional risk.
Recommended Solution
The correct solution for FANUC SV0422 alarm depends on whether the problem is caused by an unsuitable torque setting, an incorrect speed limit value, unreasonable torque control parameters, or incorrect program logic.
1. Check the Torque Setting Value
First, check the torque setting value in the torque control command.
If the torque command is too large for the machine condition, the axis may exceed the allowable speed range during torque control. Adjust the torque setting according to the actual machine requirement and control purpose.
2. Check the Speed Limit Value
Confirm whether the speed limit value specified in torque control is reasonable.
If the allowable speed is set too low, SV0422 may occur during normal torque control operation. If the speed limit is set too high, however, the machine may operate outside a safe or intended range. The value should be set according to the actual application.
3. Check Torque Control Parameters
Check the speed limit control parameters and other related torque control parameters.
The parameter settings should match the machine configuration and torque control application. If parameter values are unreasonable or were changed incorrectly, reset them according to the correct machine data.
4. Check the Torque Control Program Speed Setting
Review the speed setting used in the torque control program.
If the program commands a speed condition that exceeds the allowed torque control speed limit, modify the program so the speed remains within the permitted range.
5. Check the Torque Control Program Logic
Confirm whether the torque control program logic is suitable.
The program should correctly handle torque command output, speed limit control, mode transition, and stopping conditions. If the logic is incorrect, the axis may exceed the allowable speed during torque control and generate SV0422.
If your machine shows FANUC SV0422 torque control overspeed alarm, please contact REACO CNC directly. Our team can help check the torque setting value, speed limit value, torque control parameters, program speed setting, and torque control logic.
REACO CNC Support for FANUC SV0422 Alarm
REACO CNC provides support for FANUC CNC systems, servo control, torque control applications, parameter checking, program troubleshooting, and related CNC hardware issues.
We can help with:
- FANUC CNC alarm analysis
- FANUC SV0422 alarm troubleshooting
- Torque control overspeed issue analysis
- Torque setting value checking
- Speed limit value checking
- Torque control parameter guidance
- Torque control program speed checking
- Torque control program logic review
- Servo system and CNC function troubleshooting
- Replacement FANUC CNC parts supply
If you are not sure whether the SV0422 alarm is caused by torque command settings, speed limit values, torque control parameters, program speed settings, or torque control logic, you can send us the CNC system model, alarm screen, program condition, related parameter values, and machine application information. Our team will help check the possible cause.
FAQ About FANUC SV0422 Alarm
What is FANUC SV0422 alarm?
FANUC SV0422 alarm means torque control overspeed. It occurs when the allowable speed specified in torque control has been exceeded.
What causes FANUC SV0422 torque control overspeed alarm?
The alarm may be caused by an unsuitable torque setting value, incorrect speed limit value, unreasonable torque control parameters, excessive program speed setting, or incorrect torque control program logic.
What should I check first when SV0422 appears?
First, check the torque setting value and speed limit value in the torque control command. These two items are the main points for this alarm.
Can torque control parameters cause SV0422?
Yes. If the speed limit control parameters or related torque control parameters are not set reasonably, the CNC system may detect overspeed during torque control and generate SV0422.
Can program logic cause FANUC SV0422 alarm?
Yes. If the torque control program logic does not correctly handle torque output, speed limit control, or mode transitions, the axis may exceed the allowable speed and trigger SV0422.
How can I fix FANUC SV0422 alarm?
Check and confirm the torque setting value and speed limit value in the torque control command. Then check the speed limit control parameters, related torque control parameters, programmed speed, and torque control program logic. Adjust the settings according to the actual machine condition.
Need Help with FANUC SV0422 Alarm?
If your CNC machine has a FANUC SV0422 torque control overspeed alarm, please contact REACO CNC. We can help analyze the alarm cause and provide suitable FANUC CNC repair, torque control parameter checking, speed limit setting guidance, program logic review, or related technical support.
Reference Source: Beijing FANUC. This article is based on technical documentation provided by Beijing FANUC. For More Fanuc CNC repair Cases and technical articles, please back to Fanuc Technical Support Center.
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