Users’ Manual
ESM-40S High sensitivity settlement monitoring system
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1 INTRODUCTION
1.1 ESM-40S high sensitivity liquid level settlement system
The Encardio-rite model ESM-40S liquid level settlement system is a precision settlement measuring
system designed for remote measurement of small settlements at multiple spots or locations with high
resolution.
It employs a number of settlement monitoring sensors connected together with a common liquid line. Each
settlement monitoring sensor is equipped with a low pressure, high sensitivity digital transducer (with SDI-
12 interface or Modbus output) to measure the liquid head with respect to the reservoir. One of the
settlement measuring sensors in a system is installed near reservoir, at a stable reference location where
either no significant settlement is expected or its elevation can be precisely determined by conventional
surveying methods. Settlement of all other sensors are measured with reference to this reference sensor.
In practice the liquid vessel of each settlement monitoring sensor in a system are connected together with
a liquid line or tubing so the level of liquid in each sensor tries to find a common level. If any settlement
monitoring sensor goes up relative to the reference sensor liquid drains out of the liquid chamber to
maintain the common liquid level. Similarly, if any of the sensor goes down more liquid fills in the sensor
liquid chamber thus raising the level of the liquid inside the sensor. A larger liquid reservoir chamber at the
reference location is also connected to the common liquid line to supply or absorb the liquid draining in or
out of the sensors due to their upwards or downwards movement thus keeping the common liquid level at
more or less the initially fixed level.
The digital sensors are supplied in two options - SDI-12 serial interface or Modbus (RS-485) output. The
sensors are user friendly and convenient to configure. Encardio-rite model ESDL-30 datalogger can be
used for remote automatic data collection from level sensors at desired intervals. Maximum distance of
datalogger from the most distant SDI-12 settlement sensor can be up to 200 m. A maximum of 32 sensors
can be used in a chain in case the output is Modbus and maximum distance from datalogger to remotest
sensor can be 1.2 km. The datalogger has GSM/GPRS for wireless data transfer to central server (cloud
or local) to provide near real time data at client’s desk.
The ESM-40S liquid level settlement system can also be directly connected to RF Nodes and Gateway
communication network for wireless data transfer.
Real-time settlement/heave (deformation) profile helps in observing the behaviour of structural movement
during and after construction and indicates potentially dangerous conditions that may adversely affect
stability of the structure. The authorities can learn about the slightest of change taking place instantly. This
allows one to take timely decisions, increase safety, reduce project delays and be more cost effective.
1.2 Conventions used in this manual
WARNING!
Warning messages calls attention to a procedure or practice, that if not properly followed
could possibly cause personal injury.
CAUTION:
Caution messages calls attention to a procedure or practice, that if not properly followed may
result in loss of data or damage to equipment.
NOTE:
Note contains important information and is set off from regular text to draw the users’ attention.
1.3 How to use this manual
This users’ manual is intended to provide you with sufficient information for making optimum use of the
precision liquid level settlement monitoring system in your application. The manual is divided into a number
of sections. Each section contains a specific type of information. The index will help to quickly look for
specific information, when required.
