Based on your previous focus on the LVDT zero-point setting steps and the impact of zero-point offset, common errors in zero-point setting are as follows:
Cold-state positioning error: Zero-point calibration is performed without fully aligning the needle valve with the gate reference surface, resulting in hidden gaps and subsequent gate leakage during production.
Ignoring hot-state compensation: Zero-point calibration is completed only in a cold state. Failure to recalibrate and correct after the hot runner system heats up causes thermal expansion, leading to an overall shift in the zero-point reference.
Electrical positioning deviation: The true 0V center point of the LVDT output voltage is not found, causing the zero point to fall within the non-linear range, resulting in systematic deviations in the full-stroke displacement data.
Installation coaxiality deviation: The sensor probe and needle valve movement directions are not aligned, causing jamming during operation. The zero point drifts frequently with vibration, making long-term stability impossible.
Confusing reference markings: In multi-channel hot runner scenarios, the zero-point markings of different needle valves are confused, leading to completely disordered opening and closing strokes of the needle valves at each gate.
