The Encardio Rite Model EAN-90M MEMS Tiltmeter is used in the monitoring of inclination and vertical rotation in structures such as buildings, dams, etc.

Robust and robust during construction, the high-resolution tiltmeter has great temperature stability. It is equipped to have a voltage output which can be detected by any readout unit that can measure the differential voltage output.

Principle of operation

The Model EAN-90M Tiltmeter has a stainless steel housing which has the accurate accelerometer and proper signal conditioning circuit mounted inside it.

The accelerometer picks up the force due to gravity which is at the highest when the accelerometer is rotated to the tilt position of 90-degree and lowest(zero) when the angle of tilt is zero. For all the other tilt angle, the accelerometer force can be determined by the product of the sine of tilt angle and acceleration due to gravity.

The tilt sensor thus provides a bipolar DC voltage output proportional to the sine of tilt angle measured by the tiltmeter. The output is measured as zero when it is placed in an accurately vertical position.

Even though the sensor gives a moderately low-cost tilt measurement, it provides excellent resolution, long term stability and low thermal sensitivity. With the use of suitable mounting accessories which include brackets and anchors, the MEMS tiltmeter can be secured on any vertical surface, horizontal floor, or ceiling.

The difference that has to be understood here is that the Model EAN 90-M is not designed for the complete determination of tilt in structures. It is used to measure the change in the tilt of a structure to which the sensor is attached.

To calculate the change in the tilt of structure, the initial tilt reading when the instrument has been placed on the structure is recorded and subtracted from the subsequent tilt reading.

Tool and accessories

Following tools and accessories are required for proper installation of tiltmeter.

• Power drill
• Concrete / Masonry drill bit 8 mm
• Spanner 8/9, 12/13 mm
• Allen key 5 mm
• Cloth for cleaning

Read More: What Are Tiltmeters and Where Are They Used?

Installation of Tiltmeter

The MEMS Tiltmeter can be mounted on a vertical surface, or swung from the ceiling or placed on the floor with the help of suitable mounting arrangement/bracket available from Encardio Rite as optional accessories.

Let’s look at the procedure to install the instrument on a vertical surface.

• Identify the wall where the change in the tilt has to be measured. Using a drilling machine, dig an 8 mm Φ x 50 mm deep hole for Hilti anchor HSA M8 x 75 or equivalent.
• Insert anchor in the drilled hole.
• Once the anchor is placed accurately, install the tiltmeter bracket on it and secure it tightly.
• Set the MEMS tiltmeter on the installed bracket with two M6 x 20 mm Allen bolts.
• Once the above steps are done, connect the tiltmeter with the readout unit.
• Tighten anchor and Allen bolts/nuts so that the tiltmeter reads almost vertical on the read-out unit.

Let’s have a look at the Installation on the horizontal surface

• Trace the placement of the two mounting holes using the mounting bracket as a template.
• Visually ensure that the two-hole positions are almost aligned along the axis at which tilt has to be measured.
• Using a drilling machine, dig an 8 mm Φ x 50 mm deep hole for Hilti anchor HSA M8 x 75 or equivalent.
• Once that is done, place the anchors in the drilled holed.
• Mount the tiltmeter bracket on the anchor and secure it.
• Fix the tiltmeter on mounting bracket with two M6 x 20 mm Allen bolts.
• Connect tiltmeter with read-out unit.
• Tightly secure the anchors & Allen bolts/nuts to ensure that the tiltmeter reads almost vertical on the read-out unit.

Read More: Tiltmeter: How does it Work, Installation, & How to Read

Let’s look at the procedure to install the tiltmeter on the roof

• Drill 8 mm Φ x 50 mm deep hole for Hilti anchor HSA M8 x 75 or equivalent on the roof at which change in tilt has to be measured.
• Once that is done, place the anchors in the drilled holed.
• Mount the tiltmeter bracket on the anchor and secure it.
• Fix the tiltmeter on the mounting bracket with two M6 x 20 mm Allen bolts.
• Connect tiltmeter with read-out unit.
• Tighten anchor and Allen bolts/nuts so that the tiltmeter reads almost vertical on the read-out unit.

Measurement of Tilt

Encardio Rite Model EDI-53UTM portable digital read-out unit/data logger is used to read the output of the MEMS Tiltmeter. The output can be obtained from a remote location too by using an automatic data acquisition system like Encardio Rite model EDAS-10.

The tiltmeter is equipped with a 2m built-in six-core cable that can be discontinued or extended to the nearest measurement station through a suitable junction box.

When using with Encardio Rite model EDI-53UTM portable digital read-out unit, a break-out box (special junction box) having suitable circular connector is available.

Wiring Details

Connecting sensor to Encardio Rite Digital readout unit

Using a break-out box, connect the tiltmeter to the Encardio Rite model EDI-53UTM portable digital read-out unit/datalogger. The mating circular connector to the read-out unit is accommodated in the break-out box. Along with the connecter, it also contains a lightning arrestor.

Encardio Rite model EDI-53UTM portable digital read-out unit/datalogger reads sine of tilt angle when the parameter of typical tiltmeter is fed.

To read sine of tilt angle, set-up EDI-53UTM channel as follows:

Tilt angle can be calculated by sin-1(observed value). For bi-axial tilt meter, set-up two channels (one for A-axis and one for B-axis) in a similar manner.

This was all about MEMS Tiltmeter operating principle, installation procedure, and taking readings. If you have any doubts or questions, feel free to drop it in the comment section below.