1、 Overview of vibrating wire displacement sensors (crack gauges)
The vibrating wire sensor is a type of non electrical measurement sensor that is widely valued and applied both domestically and internationally. It includes a heat-treated vibrating wire detection element, consisting of a stress relieving spring connected to one end of the vibrating wire and the other end of the sliding rod. As the sliding rod is pulled, the spring begins to elongate and causes an increase in the tension of the vibrating string. The vibration frequency of the steel string also changes accordingly, and the tension is proportional to the elongation of the spring. Therefore, the change in displacement can be achieved by measuring the tension of the steel string, which is the change in the vibration frequency of the steel string.
Due to the fact that the vibrating wire sensor directly outputs the natural frequency signal of the vibrating wire, it has the characteristics of strong anti-interference ability, small influence of electrical parameters, small zero drift, small influence of temperature, stable and reliable performance, vibration resistance, and long service life.
2、 Application fields of vibrating wire displacement sensors (crack gauges)
Vibration string displacement sensors are widely used in engineering projects such as dams, bridges, rocks, concrete, soil, roads, factories, tunnels, underground chambers, and model tests to monitor the displacement, settlement, deformation, cracks, and other changes in long-term relative displacement of structural objects.
3、 Technical parameters of vibrating wire displacement sensor (crack gauge)
| Model | MLZX-XXXmm |
| Testing Range | 12.5, 25, 50, 100, 150, 200, 250, 300mm |
| Resolution ratio | 0.025%FSR |
| Linearity | 0.25%FSR |
| Temperature and drifting | ＜0.05%FSR/℃ |
| Stability | ＜0.2%FSR/Year |
| Frequency range | 1500-2800Hz |
| Temperature range | -40 ~ +60℃ |
| Coil resistance | 230Ω±10Ω |
| IP Rate | IP67 |
| Cable Type | 2-core |
4、 Naming rules for vibrating wire displacement sensors (crack gauges) products
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5、 Installation dimensions of vibrating wire displacement sensor (crack gauge) (unit: mm)
6、 Precautions for vibrating wire displacement sensors (crack gauges)
● This instrument should operate within the rated measurement range.
● When installing instrument cables, try to keep them away from electrical interference such as engines, transformers, spot welding machines, power cables, motor engines, etc. Cables are never allowed to be buried underground or transmitted together with AC power lines! Otherwise, the cable will sense electrical interference signals of other frequencies, which will cause trouble for the instrument to obtain stable readings.
● When extending cables according to on-site needs, attention should be paid to ensuring reliable waterproof sealing at the joints.
● The instrument should be handled and installed with caution, avoiding violent vibrations. To avoid any mechanical damage or deformation to instruments or components, it is important to protect the sensors, measuring rods, and their connecting ports from damage and deformation
● The instrument cable can reach up to 1000 meters (to be purchased separately). The user did not specify when placing an order, and all wires were wired to a length of 2 meters before leaving the factory.
● When the instrument has not been used for more than 12 months, it should be recalibrated before use.
7、 Detection report of vibrating wire displacement sensor (crack gauge):
