EV charging guns, vehicle inlets and charging connectors are repeatedly inserted, withdrawn, locked, unlocked and exposed to outdoor contamination during their service life. A few manual cycles cannot reveal gradual wear, locking failures, contact instability or corrosion-related problems. An automated insertion-withdrawal and environmental immersion test system combines mechanical endurance, contaminated-medium conditioning and process monitoring in one platform for connector manufacturers, EVSE suppliers, vehicle laboratories and third-party test organizations.

1. Test Scope and Applicable Standards

The system is commonly used for normal operation, insertion-withdrawal endurance, locking-device reliability, insertion-force variation and post-conditioning connection checks. Test programs may be developed with reference to GB/T 20234 series, IEC 62196 series and customer-specific connector specifications. Before testing, the laboratory should confirm whether the sample is an AC connector, DC connector or high-power interface and define travel, speed, dwell time, separation distance and acceptance criteria.

2. Main System Modules

• Servo or motor-driven linear actuator for repeatable insertion and withdrawal;
• Adjustable fixture and alignment stage for the plug, gun, coupler or vehicle inlet;
• Locking and unlocking mechanism for mechanical or electronic locking devices;
• Immersion tanks for salt solution, simulated rainwater, contaminated water or mud;
• PLC and HMI for sequence editing, cycle setting, dwell time and alarm conditions;
• Optional continuity, contact resistance, temperature-rise or electrical-load monitoring.

3. Key Technical Configuration

A typical system can provide an adjustable travel of approximately 1 to 150 mm, variable insertion speed from positioning speed to high-speed operation and a preset cycle count of tens of thousands of operations. The laboratory should program insertion speed, contact dwell, withdrawal distance and immersion duration as separate parameters. For connectors with a locking device, the sequence should include insertion, lock confirmation, dwell, unlock and withdrawal.

Fixture alignment is critical. The connector axis must remain aligned with the mating inlet so that the test does not introduce unrealistic side load. The immersion module should use corrosion-resistant containers, drainage and cleaning provisions, while keeping the drive and sensors isolated from the test medium.

4. Recommended Operating Procedure

1. Record sample identification, initial appearance, insertion force, locking function and electrical condition;
2. Adjust the fixture and confirm smooth mating without visible lateral loading;
3. Use low-speed jog mode to set insertion end position, withdrawal end position and safety limits;
4. Set speed, dwell time, immersion medium, conditioning time, cycle count and stop conditions;
5. Run a small number of trial cycles to verify the sequence, sensors and locking mechanism;
6. Start the endurance test and perform periodic inspections of force, wear, continuity and temperature rise;
7. Clean the sample after testing and compare final measurements with the initial condition.

5. Data Evaluation

Completion of the target cycle count is not the only acceptance criterion. The laboratory should evaluate insertion-force drift, locking delay, terminal loosening, contact-resistance instability, insulation cracking, corrosion and sealing damage. If continuity loss, incomplete mating or abnormal drive force occurs, the machine should stop automatically and retain the cycle number and alarm record.

6. Selection and Maintenance

When specifying the equipment, provide connector samples, drawings, maximum insertion force, sample mass, test media, target cycles and electrical-load requirements. Multi-model laboratories benefit from quick-change fixtures and recipe-based control. Routine maintenance should include guide lubrication, alignment verification, tank cleaning, sensor calibration and safety-interlock testing. Shenzhen LSKFT Testing Instruments Co., Ltd. can configure insertion endurance, contaminated-medium conditioning, electrical monitoring and data-recording functions according to the applicable connector standard and sample structure.