The qualified inspection of electric actuators requires comprehensive evaluation from multiple aspects, including performance testing, functional verification, safety and environmental adaptability. The following are detailed inspection steps and methods:
Recommended inspection tools- multimeter, megohmmeter, oscilloscope, torque tester, signal generator, environmental test chamber, etc.
Appearance and mechanical structure inspection
1. Appearance inspection: Confirm that the shell is not deformed, scratched, or rusted, and the markings are clear (model, voltage, current, etc.).
2. Mechanical parts: Check whether the transmission mechanism (gears, screws, etc.) is flexible, without jamming or abnormal wear.
3. Sealing: For waterproof/dustproof models (such as IP65 and above), check whether the sealing ring is intact and perform waterproof test if necessary.
Electrical performance test
1. Insulation resistance test: Use a megohmmeter to measure the insulation resistance between the power terminal and the shell (usually required to be ≥100MΩ, 500VDC).
2. Withstand voltage test: Apply 1.5 times the rated voltage (or according to the standard such as 1500VAC/1 minute) to verify the insulation strength, without breakdown or leakage.
3. Voltage range test: Test whether it can start and run normally within the range of ±10% of the rated voltage (such as 220VAC±10%).
Basic function verification
1. Stroke control: Open/close position accuracy: Test whether the full open and full closed positions are accurate, and repeat positioning errors (such as ±0.5° or ±1mm). Limit switch: Manually or automatically trigger the limit to confirm that the actuator can stop accurately and the signal output is normal.
2. Signal feedback: Check whether the 4-20mA, 0-10V or switch signal matches the position (such as 0% corresponds to 4mA, 100% corresponds to 20mA). Verify the linearity of the potentiometer or encoder feedback.
3. Manual operation: Test whether the manual mode (handwheel or clutch device) can be switched and operated normally.
Dynamic performance test
1. Running speed: measure whether the full stroke time meets the nominal value (such as 30 seconds/90°).
2. Torque/thrust test: Use a torque meter or load sensor to verify whether the rated torque (such as 50Nm) meets the standard.
3. Overload protection test: Apply 120% of the rated load to check whether the overload protection or alarm is triggered. Noise and vibration: Monitor abnormal noise during operation, and the vibration amplitude should meet the standard (such as ≤0.1mm/s).
Communication and protocol test (intelligent actuator)
1. Bus communication: Test whether Modbus, Profibus and other protocols can read and write parameters normally.
2. HART/Bluetooth configuration: Verify whether the remote configuration and diagnostic functions are effective.
Environmental adaptability test
1. High temperature/low temperature test: Test the startup and operation stability within the nominal temperature range (such as -30℃~+70℃).
2. Humidity test: Run in an environment with 85% humidity to check whether the insulation performance is reduced.
3. Protection level: Water spray (IP65) or immersion test (IP67) according to IP level.
Safety and protection function
1. Overheat protection: simulate motor overheating, check whether it automatically cuts off the power and alarms.
2. Phase sequence protection (three-phase motor): change the phase sequence to verify whether it alarms or refuses to run.
3. Emergency stop: test whether the external ESD signal can immediately cut off the power.
Life test (sampling)
1. Mechanical life: continuous operation of the rated number of cycles (such as 100,000 times), check wear and performance degradation.
2. Electrical life: frequent start and stop test contactor or relay durability.
Through the system detection of the above steps, it can be ensured that the electric actuator meets the qualified standards in terms of performance, safety and reliability. For batch acceptance, it is recommended to conduct random inspections according to the AQL sampling standard.