Insensitive Elevator Light Curtains: Causes & Replacement Tips
In modern elevator systems, the elevator light curtain is one of the key safety components designed to protect passengers. It detects whether people or objects enter the doorway during door opening and closing. Once the light curtain becomes slow to respond or less sensitive, it can lead to passenger or object entrapment, increasing safety risks and potentially causing accidents. Therefore, correctly identifying the cause of light curtain malfunction and replacing it when necessary is a critical part of elevator maintenance.
As a professional elevator and escalator spare parts supplier, A-FLY has found through numerous projects that an “insensitive” elevator light curtain is rarely caused by a single factor — it is often the result of multiple issues combined.
1. Surface Contamination or Aging
After long-term operation, dust, oil, and moisture can accumulate on the emitter and receiver surfaces of the light curtain, directly affecting the stability of infrared signal transmission. In high-traffic or dusty environments, reduced sensitivity is very common. Additionally, aging internal electronic components in older light curtains can slow down response speed.
2. Installation Misalignment or Loose Mounting
Continuous vibration from elevator door movement may loosen mounting brackets or shift the installation angle of the light curtain, causing the emitter and receiver signals to lose precise alignment. In such cases, the light curtain may appear to be functioning but responds slowly to small or fast-moving obstacles.
3. Unstable Power Supply or Signal Issues
Voltage fluctuations, loose terminals, or aging signal cables can all cause unstable operation. Some light curtains may still show indicator lights under abnormal power conditions, but their detection performance may already be significantly reduced, leading to misjudgment as “intermittent faults.”
4. Environmental Interference
Direct strong light, reflective metal surfaces, or electromagnetic interference can all disrupt normal light curtain detection. These environmental factors are especially common in older elevators or modernization projects.
5. Model Mismatch or Poor Compatibility
When replacing elevator components, if the light curtain model does not match the door operator system or control logic, even a brand-new unit may show delayed response or false triggering.
When Should an Elevator Light Curtain Be Replaced?
If frequent false entrapment alarms occur, door closing reactions become noticeably slow, adjustments are ineffective, or the unit has exceeded its design service life, replacing it with a high-quality light curtain is the safer and more cost-effective solution.
A-FLY Professional Recommendation
A-FLY provides a wide range of high-sensitivity, anti-interference elevator light curtain solutions compatible with different door operator systems and application environments. Choosing reliable elevator spare parts not only reduces failures but also significantly improves overall elevator safety performance.
