Maintenance Guide for Surface Mount Technology (SMT) Machine Drive and Motor System

Maintenance Guide for Surface Mount Technology (SMT) Machine Drive and Motor System

Function description of core components
Common brands of component functions
Servo motors control the precise movement of the placement head (X/Y/Z axes), Panasonic, YASKAWA
The core power source for high-speed mounting of linear motors (such as FUJI NXT) Siemens
The drive controller parses the motion instructions and outputs current signals Delta and Mitsubishi
The encoder provides real-time feedback on the motor position accuracy (±0.01mm) HEIDENHAIN
I. Daily Maintenance and Care Standards
1. Cleaning and dust prevention management
Weekly tasks:

Clean the motor heat dissipation fins with anhydrous ethanol (to prevent overheating and burning out);

Clean the ventilation filter screen of the drive controller with a vacuum cleaner and an anti-static brush (dust accumulation causes overheating failure rate ↑30%).

Taboo: Do not directly blow compressed air onto the encoder (it may damage the optical grid).

2. Maintenance of mechanical components
Lubrication

Apply lithium-based grease (such as Mobilith SHC 100) to the guide rails of linear motors and replenish it every 500 hours.

The lead screw drive mechanism uses ISO VG32 grade lubricating oil (such as THK AFB-E).

Fastening: Check the torque of the motor installation bolts monthly (refer to the equipment manual, for example, YAMAHA requires 10±1N·m).

3. Electrical system inspection
Cable status:

Check whether the motor power cord/encoder cord is worn (broken skin may cause a short circuit);

Shake the test connector (a loose connection will cause an alarm at the ERR-410 position).

Grounding resistance: Quarterly detection of the grounding resistance of the drive cabinet ≤4Ω (to prevent static interference).

Ii. Diagnosis and Handling of Critical Faults
Common Alarm Codes and Responses
Possible causes of alarm codes and emergency handling steps
ERR-410 encoder feedback loss 1. Check the encoder connection
2. Clean the optical reader
ERR-720 driver overload (Current over-limit) 1. Measure the motor winding resistance (standard 1-2Ω)
2. Check for mechanical jamming
ERR-500 bus communication timeout 1. Restart the driver controller
2. Replace the communication optical fiber
Judgment of motor performance attenuation
Test method:

Run the mounting head without load and record the current value at the rated speed (15% higher than the initial value requires a warning).

The vibration velocity of the motor was detected by a laser vibrometer (> 4.5mm/s indicates bearing wear).

Replacement threshold: Winding insulation resistance < 100MΩ (measured with a 500V megohmmeter).

Iii. In-depth Strategies for Preventive Maintenance (PM)
Monthly PM process
Driver detection:

The oscilloscope measures the output current waveform (a distortion rate > 5% indicates the aging of the IGBT module);

Clean the dust on the circuit board (brush + vacuum cleaner, do not use liquids).

Motor maintenance

The thermal imager scans the temperature rise (the casing needs to be shut down for maintenance if it exceeds 65℃).

High-temperature grease (such as SKF LGHP2) is injected into the bearings.

Annual major maintenance
Disassemble the motor

Replace the bearings (NSK, SKF brands);

Clean the stator windings (soaked in special volatile oil);

Drive maintenance:

Replace the cooling fan (with a lifespan of approximately 20,000 hours);

Test the capacity of the electrolytic capacitor (replace it when it decays by 20%).

Four. Advanced Techniques for Prolonging Life
Reduce electrical stress
Install servo dedicated reactors (to suppress high-frequency harmonics and reduce winding heating);

The power supply configuration of the driver is a voltage-stabilizing UPS (voltage fluctuation ≤±10%).

2. Optimization of motion parameters
Adjust the acceleration and deceleration curves (such as S-shaped curves to reduce mechanical shock);

Hard collisions beyond the range limit are prohibited (rubber buffers should be installed).

3. Spare Parts Management
Reserve key spare parts: encoder modules, driver board power ics (such as Mitsubishi J2 series IPM);

Reuse of old parts: Disassemble scrapped motors to recycle magnets and coils.

V. Classic Fault Cases
Problem: The FUJI NXTⅢ surface mount technology (SMT) machine of a certain factory frequently reports "Z-axis overload" (ERR-720).

Diagnosis process:

Measure the motor current (no-load 3.2A > standard value 2.5A);

Disassembly revealed that the lubricating grease on the guide rail had dried up, causing the resistance to double.

Solution:

Clean the guide rails and apply fully synthetic grease;

Calibrate the pressure of the Z-axis balance cylinder.

Result: The failure interval was prolonged from 3 days to 11 months.

Comparison of maintenance effectiveness
The indicator has no PM maintenance specification PM maintenance
The average lifespan of the motor is 1.5 to 2 years and 4 to 5 years
The frequency of unexpected shutdowns is 2 to 3 times per month and less than 0.5 times per month
The stability of the mounting accuracy is ±0.05mm and the fluctuation is ±0.02mm
Ultimate suggestion: Establish a "Drive - Motor Health File" to record each maintenance data (current/vibration/temperature rise) and predict faults through trends!