Users’ Manual
ESM-40S High sensitivity settlement monitoring system
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The fluid level in the reference reservoir is maintained constant and monitored with the measuring tube of
the reservoir. An air vent tube connects all the sensors to the moisture trap. This eliminates any error due
to barometric pressure variation.
Settlement or heave of any sensor installed at settlement location, causes difference in elevation between
the sensor and reference reservoir, resulting in change in liquid head, which is read by the low level pressure
transducer
.
Settlement of sensor gives a higher liquid head while heave results in a lower liquid head.
The low range pressure transducer of the settlement sensor has a digital output. All the sensors are
connected in series with a single 3 core signal cable. The signal cable is connected to our model ESDL-30
compact digital datalogger for remote online monitoring. With ESDL-30 datalogger and its configuration
software, it is quite easy and fast to configure the whole system.
2.3 ESM-40S/1 Settlement sensor
Two or more high precision settlement sensors are used in the settlement monitoring system. One of the
sensor is installed near the reservoir, as a reference sensor (at a stable location). Each settlement sensor
consists of a low range pressure transducer with high sensitivity that monitors the head of liquid, quick
connectors to connect fluid and air vent tubes, drain valve, male connector for signal cable and wall
mounting fixing plate.
Figure 2-2 Settlement sensor
2.4 ESM-40S/2 Reservoir assembly
The reservoir assembly consists of a reference tank containing the fluid. A level measuring scale is
provided to know the level of fluid inside tank. It is supplied with wall mounting plates attached, and with
suitable fasteners. Capacity of the reservoir is 6 litre. Maximum and minimum water level is marked.
Figure 2-3 Reservoir (reference tank)
