Based on your previous focus on the zero-point setting, deviation correction, and calibration of LVDT sensors in hot runner scenarios, you can determine if an LVDT is working properly using the following methods:
Appearance and Wiring Inspection: Check the sensor body for high-temperature burns and mechanical deformation, ensure the shielded signal cable is undamaged and has no loose connections, and confirm that the power supply voltage is within the rated range, with no short circuits or open circuits.
Zero-Point Signal Verification: Fix the probe in the mechanical zero position and use a multimeter to test the output voltage. Confirm that the value is stable and close to 0V, with a deviation controlled within ±1mV, and no drift or jumps.
Full-Stroke Linearity Verification: Manually drive the probe to complete the preset full stroke, recording the output voltage point by point. Confirm that the voltage changes linearly with displacement, with a full-stroke linearity error ≤0.5%, and no stuttering or signal jumps.
Hot Condition Verification: Heat the hot runner to the operating temperature and hold for 2 hours. Confirm that there is no zero-point drift under hot conditions, the displacement feedback is completely synchronized with the actual action of the needle valve, and no alarm triggering.
