Geokon 6160 User manual

No part of this instruction manual may be reproduced, by any means, without the written consent of Geokon®.
The information contained herein is believed to be accurate and reliable. However, Geokon®assumes no responsibility for errors,
omissions or misinterpretation. The information herein is subject to change without notification.
Copyright © 2006-2019 by Geokon®
(Doc Rev T, 05/01/2019)
Installation Manual
Model 6160/6161
MEMS Tilt Sensor

Warranty Statement
Geokon warrants its products to be free of defects in materials and workmanship, under normal
use and service for a period of 13 months from date of purchase. If the unit should malfunction,
it must be returned to the factory for evaluation, freight prepaid. Upon examination by Geokon,
if the unit is found to be defective, it will be repaired or replaced at no charge. However, the
WARRANTY is VOID if the unit shows evidence of having been tampered with or shows
evidence of being damaged as a result of excessive corrosion or current, heat, moisture or
vibration, improper specification, misapplication, misuse or other operating conditions outside of
Geokon's control. Components which wear or which are damaged by misuse are not warranted.
This includes fuses and batteries.
Geokon manufactures scientific instruments whose misuse is potentially dangerous. The
instruments are intended to be installed and used only by qualified personnel. There are no
warranties except as stated herein. There are no other warranties, expressed or implied, including
but not limited to the implied warranties of merchantability and of fitness for a particular
purpose. Geokon is not responsible for any damages or losses caused to other equipment,
whether direct, indirect, incidental, special or consequential which the purchaser may experience
as a result of the installation or use of the product. The buyer's sole remedy for any breach of this
agreement by Geokon or any breach of any warranty by Geokon shall not exceed the purchase
price paid by the purchaser to Geokon for the unit or units, or equipment directly affected by
such breach. Under no circumstances will Geokon reimburse the claimant for loss incurred in
removing and/or reinstalling equipment.
Every precaution for accuracy has been taken in the preparation of manuals and/or software,
however, Geokon neither assumes responsibility for any omissions or errors that may appear nor
assumes liability for any damages or losses that result from the use of the products in accordance
with the information contained in the manual or software.

TABLE of CONTENTS
1. INTRODUCTION ...................................................................................................................................................1
2. INSTALLATION ....................................................................................................................................................3
2.1 PRELIMINARY TESTS............................................................................................................................................3
2.2 INSTALLING MODEL 6160 SENSORS ....................................................................................................................3
2.2.1 Mounting Brackets ......................................................................................................................................3
2.2.2 Mounting the Sensor ...................................................................................................................................6
2.2.3 Sensor Protection........................................................................................................................................7
2.3 INSTALLING MODEL 6161 SENSORS ....................................................................................................................7
2.3.1 A Axis Tilt Adjustments ...............................................................................................................................8
2.3.2 B Axis Tilt Adjustments ...............................................................................................................................8
2.4 JUNCTION BOXES.................................................................................................................................................9
2.5 SPLICING..............................................................................................................................................................9
3. TAKING READINGS...........................................................................................................................................10
3.1 DATALOGGERS ..................................................................................................................................................10
3.2 RB-500 READOUT BOX .....................................................................................................................................10
3.3 MEASURING TEMPERATURE ..............................................................................................................................10
4. DATA REDUCTION ............................................................................................................................................11
4.1 TILT CALCULATION ...........................................................................................................................................11
4.2 TEMPERATURE CORRECTION .............................................................................................................................11
4.3 ENVIRONMENTAL FACTORS...............................................................................................................................11
5. TROUBLESHOOTING........................................................................................................................................12
APPENDIX A. SPECIFICATIONS.........................................................................................................................13
A.1 MEMS TILT SENSOR ........................................................................................................................................13
A.2 THERMISTOR.....................................................................................................................................................13
APPENDIX B. THERMISTOR TEMPERATURE DERIVATION...... ERROR! BOOKMARK NOT DEFINED.
APPENDIX C. SAMPLE CALIBRATION REPORT ...........................................................................................14
APPENDIX D. WIRING CODES ............................................................................................................................16
APPENDIX E. 6160 STANDARD ADDRESSABLE SYSTEMS..........................................................................17
APPENDIX F. PROGRAMMING THE MEMS TILTMETER WITH CRBASIC ............................................19
APPENDIX G. PROGRAMMING THE ADDRESSABLE MEMS TILTMETER WITH CRBASIC.............20

FIGURES
FIGURE 1-MODEL 6160 MEMS TILT SENSOR.............................................................................................................. 1
FIGURE 2-MOUNTING BRACKET FOR THE MODEL 6160 TILT SENSOR ......................................................................... 1
FIGURE 3-MODEL 6161A TILT SENSOR (VERTICAL ORIENTATION,BIAXIAL MODEL SHOWN)..................................... 2
FIGURE 4-MODEL 6161B TILT SENSOR (VERTICAL ORIENTATION,BIAXIAL MODEL SHOWN) ..................................... 2
FIGURE 5-TILTMETER MOUNTING BRACKETS.............................................................................................................. 3
FIGURE 6-DROP-IN ANCHOR INSTALLATION ................................................................................................................ 4
FIGURE 7-ANCHOR ROD .............................................................................................................................................. 5
FIGURE 8-UNIAXIAL OR BIAXIAL TILTMETER INSTALLATION DETAILS ....................................................................... 6
FIGURE 9-ADJUSTMENT SCREW LOCATIONS................................................................................................................ 8
FIGURE 10 -SAMPLE MODEL 6160 CALIBRATION REPORT...........................................................................................15
TABLES
TABLE 1-MODEL 6160 AND 6161 TILT SENSOR SPECIFICATIONS................................................................................13
TABLE 2-THERMISTOR RESISTANCE VERSUS TEMPERATURE...............................ERROR!BOOKMARK NOT DEFINED.
TABLE 3-CABLE 03-250V0 WIRING............................................................................................................................16
TABLE 4-ADDRESSABLE MEMS (LOGIC LEVEL STYLE)WIRING ...............................................................................17
TABLE 5-THERMISTOR BRIDGE CIRCUIT.....................................................................................................................18
EQUATIONS
EQUATION 1-INCLINATION VERSUS VOLTS ................................................................................................................11
EQUATION 2-TILT VERSUS VOLTS ..............................................................................................................................11
EQUATION 3-TILT VERSUS VOLTS CORRECTED FOR TEMPERATURE ..........................................................................11
EQUATION 4-CONVERT THERMISTOR RESISTANCE TO TEMPERATURE .................ERROR!BOOKMARK NOT DEFINED.

1
1. INTRODUCTION
The Geokon Model 6160 MEMS Tilt Sensor is designed for permanent long-term monitoring of
changes in tilt of structures such as dams, embankments, foundation walls, retaining walls,
buildings, and the like. There are two main types of Tilt Sensors: The Model 6160 is an adaption
of the tiltmeter used in Model 6150 In-Place Inclinometer, and the 6161 utilizes the same MEMS
sensors inside a Nema 4 enclosure. Examples of each type are shown in the Figures below. Each
style of housing contains either one or two Micro-Electro-Mechanical Systems (MEMS) sensors
oriented at 90 degrees to measure biaxial tilts. All types include a thermistor for measuring
temperatures.
They are designed to be attached to the structure so that they can sense and measure any tilting of
the structure in uniaxial or biaxial directions. Angular changes of as little as two arc seconds can
be detected.
Figure 1 - Model 6160 MEMS Tilt Sensor
Figure 2 - Mounting Bracket for the Model 6160 Tilt Sensor

2
Figure 3 - Model 6161A Tilt Sensor (Vertical Orientation, Biaxial model shown)
Figure 4 - Model 6161B Tilt Sensor (Vertical Orientation, Biaxial model shown)

3
2. INSTALLATION
2.1 Preliminary Tests
Prior to installation, the sensors need to be checked for proper operation. Each tilt sensor is
supplied with a calibration report, which shows the relationship between output voltage and
inclination. The tilt sensor electrical leads are connected to a Datalogger or the RB-500 readout
box (see Section 3 for readout instructions) Hold the sensor in an approximately vertical position
and observe the reading. The sensor must be held in a steady position. The current reading
should be close to the factory vertical reading provided on the calibration report. (See Appendix
C. for a sample calibration report.) The temperature indicated by the thermistor should be close
to the ambient temperature.
Checks of electrical continuity can also be made using an ohmmeter. Resistance between any
conductor and the shield or the case should exceed two megohms.
2.2 Installing Model 6160 Sensors
2.2.1 Mounting Brackets
The first step is to install the uniaxial/biaxial mounting bracket (Figure 5), which is
designed for mounting on vertical walls. The bracket may be mounted using a drop-in
anchor or an anchor rod that is epoxied or grouted in place. See Section 2.2.1 for
instructions using drop-in anchors, and Section 2.2.2 for anchor rods.
Figure 5 - Tiltmeter Mounting Brackets

4
2.2.1.1 Mounting with a Drop-in Anchor
1) Mark the location where the bracket will be installed.
2) Using a hammer drill, drill a 12 mm (0.5") hole approximately 37 mm (1.5") deep.
Clean the hole thoroughly, blowing out with compressed air if possible.
3) Insert the 3/8" drop-in anchor with setting pin into the hole. The threaded end should
be closest to the opening.
4) Insert the provided setting tool, small end first, into the anchor. Expand the anchor by
hitting the large end of the setting tool with several sharp hammer blows.
5) Thread the supplied 3/8-16 anchor rod into the anchor.
6) Attach the mounting bracket to the bolt using the supplied hardware, as illustrated in
Figure 6.
7) Use a leveling device to align the bracket vertically to the wall.
Figure 6 - Drop-in Anchor Installation
Top
View
Tilt A
_
+
Flat Washer
2" 3/8
-
16 Anchor Rod
Flat Washers
Lock Washer
3/8
-
16 Nuts
Wall
3/8" Drop
-
In Anchor
Setting Pin
Tilt B
+
_
10-32 Nuts
10-32 Cap Screws