The ESM-40S high-sensitivity liquid level settlement system is designed for remote measurement of minute differential settlement in tunnels, bridges, buildings, etc. with high precision. It consists of low-pressure, high-sensitivity settlement sensors with digital output, connected in series to a reference reservoir and desiccant unit via fluid-filled and air vent tubes, respectively.
All interconnected settlement sensors are mounted at the same elevation. They are connected in series by a fluid-filled tube to a reference sensor mounted on stable ground at the same elevation. The settlement sensors and the reference sensor have a common fluid level initially. The fluid level in the reference reservoir is maintained almost constant. Settlement or heave of any sensor installed at settlement locations causes a difference in elevation between the sensor and reference reservoir, resulting in a change in liquid head, which is read by the settlement transducer.
The settlement sensors are interconnected with an air vent tube terminated in a desiccant unit with a moisture trap. The common vent line being open to the atmosphere results in the settlement reading not being affected by local air currents and changes in atmospheric pressure.
Data for remote online monitoring is retrieved from the sensors by the Encardio-rite model ESDL-30, a digital datalogger. With real-time data, authorities can monitor the slightest changes taking place instantly. This allows for taking timely decisions, resulting in increased safety, cost effectiveness, and reduced project delays.
| Range | 1000 mm; can be calibrated to 500 mm |
| Sensor resolution | 0.01 mm |
| Sensor accuracy | Better than ± 0.4 mm |
| Output signal | SDI-12 serial interface or Modbus (RS-485) |
| Temperature limit | -20° to 80°C |
| Protection | IP-67 |