Industrial Vibration Sensors: The ‘Eyes’ of Equipment Health

In modern industrial production, the health status of equipment directly determines the stability, efficiency, and economic benefits of the production line. As a key intelligent device for equipment health monitoring, vibration sensors can accurately capture subtle abnormal signals during equipment operation, providing crucial data support for preventive maintenance. This article will comprehensively explore the working principles, application scenarios, and intelligent monitoring strategies of industrial vibration sensors in PLC systems.

A vibration sensor is a high-precision instrument that can accurately convert complex mechanical vibrations into electrical signals. In the complex industrial field, it acts like a “health check doctor” for equipment, capable of real-time monitoring of the vibration characteristics and operating status of machinery. Taking large rotating equipment such as motors, fans, and centrifugal pumps as examples, vibration sensors can sensitively capture potential fault signals such as bearing wear, rotor imbalance, and shaft misalignment, providing key clues for equipment maintenance.

The core parameters monitored by vibration sensors include three dimensions:

1. Vibration Amplitude
   
   : Directly reflects the intensity of vibration and is a basic indicator for judging equipment anomalies.
2. Vibration Frequency
   
   : Reveals the characteristic frequency spectrum of vibration, which can diagnose specific fault types.
3. Vibration Acceleration
   
   : Reflects the severity of vibration and is an important basis for assessing equipment health.

These three parameters are like a “physical examination report” for equipment operation, providing a comprehensive reflection of the operational status.

Taking the Siemens S7-1200 as an example of a medium PLC, vibration sensors are typically connected to the analog input, with a typical signal access scheme as follows:

+-----[AI1]-----+
|               |
[ Vibration Sensor ]----[ Signal Conditioning Circuit ]----[ PLC Analog Input]

The following is a simple vibration anomaly judgment program that triggers an alarm when the vibration exceeds a preset threshold:

+---[ >1.5 ]---+
|              |
AI1---+     M0.0     |
|
+---[ TON ]----+
T37

• Carefully select the matching sensor measurement range.
• Regularly perform professional sensor calibration.
• Pay attention to electromagnetic interference design.
• Select appropriate sensor installation positions and orientations.
• Configure a reasonable signal filtering circuit.

In actual industrial sites, different vibration characteristics often correspond to different types of equipment faults:

• High-frequency vibration: Usually indicates bearing wear or damage.
• Low-frequency vibration: May be due to uneven foundations or loose bases.
• Pulsating vibration: Likely indicates intermittent mechanical collisions or loose parts.
• Continuous vibration: May involve imbalance of rotating components.

During the installation and debugging of vibration sensors, it is essential to strictly adhere to the following safety regulations:

1. Power supply to the equipment must be completely cut off before work.
2. Wear appropriate insulating protective gear.
3. Strictly follow on-site safety operation regulations.
4. Do not debug in the absence of professionals.

Through advanced vibration sensor technology, engineers can achieve dynamic and precise monitoring of equipment status, foresee potential faults in advance, effectively reduce the risk of unexpected equipment downtime, safeguard industrial production, and maximize production efficiency and economic benefits.