Description
The JM series employs a vibrating wire sensor attached to a spring under tension between two anchors. Any change in distance between the anchors alters the wire tension, which is measured by the sensor housed in a sliding stainless steel casing for protection.
Models Available:
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JM-S Crackmeter: Surface-mounted on structures using groutable or bolt-on anchors. Equipped with ball joints at both ends to accommodate anchor misalignment. Available in 3-D configuration for measurement in three orthogonal directions or with special clamps for geogrid installation.
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JM-E Embedment Jointmeter: Embedded within concrete, spanning the construction joint. Installed in two parts (socket and sensor) during successive concrete pours.
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JM-T: Designed for use with borehole extensometers.
All models include an integrated thermistor for temperature measurement.
Specifications:
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Measurement Range: 25 to 300 mm (depending on model)
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Overrange Capacity: 100% of range
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Accuracy: ±0.25% F.S. (±0.1% optional)
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Resolution: 0.02% F.S. minimum
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Operating Temperature: −20°C to +80°C
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Thermistor Resistance: 3 kΩ
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Cable Types: IRC-41A, IRC-41AP, IRC-3902, IRC-21A (JM-T)
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Dimensions vary by model and range
