How to solve the alarm problem of the CNC lathe driver

文章作者:yuanjie 日期:2025-12-17 阅读量:
For the alarm problem of the CNC lathe driver, based on industry experience cases, I have sorted out a systematic solution for you, which is divided into two steps: ‌ quick troubleshooting ‌ and ‌ deep repair ‌, and attached typical case references:
东莞市远杰实业有限公司
1. Quick Troubleshooting: Locate the type of fault within 3 minutes
 
Youdaoplaceholder0 1. Observe the alarm code ‌
 
Youdaoplaceholder0 overcurrent/overload alarm (such as HC/OL) ‌ : Check if the mechanical load has suddenly changed (such as lead screw jamming, excessive cutting volume), or if the driver's cooling fan has stopped rotating.
 
Youdaoplaceholder0 overvoltage/undervoltage alarm (such as UV/LV) ‌ : Use a multimeter to measure whether the grid voltage is stable (special attention should be paid to three-phase imbalance), or whether the capacitor of the power module is bulging.
 
Youdaoplaceholder0 encoder alarm (such as ENC ERR) ‌ : Check whether the encoder cable is damaged (pay particular attention to the shielding layer), or whether the connection between the motor and the encoder is loose.
 
Youdaoplaceholder0 Communication alarm (such as COMM ERR) ‌ : Confirm whether the communication protocol (such as RS485/Profinet) Settings are correct and whether the cable is subject to electromagnetic interference (such as near the frequency converter).
 
Youdaoplaceholder0 2. Locate by sound ‌
 
The driver makes a "sizzling" sound: It might be due to the breakdown of the IGBT power transistor or the failure of the capacitor.
 
Abnormal noise from the motor: Abnormal position feedback caused by bearing wear or encoder failure.
 
Youdaoplaceholder0 3. Tactile examination ‌
 
Touch the driver housing: If it is hot to the touch and the alarm code is OH (overheating), clean the dust on the heat sink or replace the cooling fan.
 
Check the motor plug: If water or oil stains have entered, clean it with alcohol and carry out waterproof treatment.
 
Ii. Deep Repair: Targeted Solutions
 
Youdaoplaceholder0 Case 1: Guangshu 980TA lathe X-axis drive alarm (not overtraveled) ‌
 
Youdaoplaceholder0 phenomenon ‌ : when the X-axis does not move and the z-axis reaches halfway, the X-axis alarms.
 
Youdaoplaceholder0 Cause ‌ : Abnormal 24V output of the power box, or the alarm line from the system to the driver is disconnected.
 
Youdaoplaceholder0 solves ‌ :
 
Check the 24V output of the power box (normally it should be 24V±5%).
 
Use an oscilloscope to detect the alarm line signal (for low-level alarms, confirm the parameter Settings).
 
If the power cable of the driver breaks, it needs to be re-welded and insulated.
 
Youdaoplaceholder0 Case 2: Z-axis servo fault in Siemens 840D SL system (alarm at 25201) ‌
 
Youdaoplaceholder0 phenomenon ‌ : The feed cable of shaft Z1 motor is out of phase.
 
Youdaoplaceholder0 Cause ‌ : short circuit of the motor winding, or damage to the power devices of the driver.
 
Youdaoplaceholder0 solves ‌ :
 
Measure the three-phase resistance of the motor with a multimeter (the balanced value should be ≤5%).
 
Check the IGBT module of the driver (if it is punctured, replace it and re-debug the parameters).
 
Run the motor under light load in manual mode and observe whether it runs smoothly.
 
Youdaoplaceholder0 Case 3: New generation system Z-axis servo alarm (MLC-020) ‌
 
Youdaoplaceholder0 phenomenon ‌ : An alarm is triggered when the z-axis fails to return to the origin.
 
Youdaoplaceholder0 Reason ‌ : the setting value of the soft limit parameter is less than the position value of the return-to-zero deceleration switch.
 
Youdaoplaceholder0 solves ‌ :
 
Set the soft limit parameter to a large value (for example, MD5002=999999).
 
Re-execute the reset operation and observe whether the alarm disappears.
 
Iii. Preventive Maintenance Suggestions
 
Youdaoplaceholder0 Regular cleaning ‌ : Use compressed air to clean the dust accumulated on the driver's heat sink every quarter to prevent overheating alarms.
 
Youdaoplaceholder0 Parameter backup ‌ : After each modification of the driver parameters, back them up to a USB flash drive (for Fanuc systems, it can be backed up via a CF card).
 
Youdaoplaceholder0 Spare parts management ‌ : It is recommended to stock 1-2 vulnerable parts (such as cooling fans and electrolytic capacitors) to shorten the maintenance cycle.
 
If you need a more specific solution (such as the alarm code analysis of a certain brand of driver), you can tell me your lathe model and alarm code. I will further analyze it in combination with practical operation cases!