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Installation Manual Model 6160/6161 MEMS Tilt Sensor 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 ®...
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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.
APPENDIX C. SAMPLE CALIBRATION REPORT ................... 15 APPENDIX D. WIRING CODE ..........................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...
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FIGURES 1 - M 6160 MEMS T ......................1 IGURE ODEL ENSOR 2 - M 6160 T ................. 1 IGURE OUNTING RACKET FOR THE ODEL ENSOR 3 - M 6161A T ........................2 IGURE ODEL ENSOR 4 - M 6161B T ........................
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.
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) and the current reading compared to the calibration readings.
2.2.1 Mounting with a Drop-in Anchor 1) Mark the location where the bracket will be installed. 2) Using a hammer drill, drill a half inch (12 mm) hole approximately 1.5" (37 mm) deep. Clean the hole thoroughly, blowing out with compressed air if possible. 3) Insert the 3/8"...
2.2.2 Mounting with an Anchor Rod 1) Mark the location where the bracket will be installed. 2) Using a hammer drill, drill a half inch (12 mm) hole approximately four inches (100 mm) deep. 3) Clean the hole thoroughly, blowing out with compressed air if possible. 4) Mix the grout or epoxy and fill the hole.
2.3 Sensor Installation 2.3.1 Installing Uniaxial Tiltmeters Attach the tiltmeter to the mounting bracket using the supplied 10-32 cap screws, washers, and nuts. Remove the slotted head locking clamp screw completely and replace with the Phillips head seal screw (provided). This is very important if the sensor is to remain waterproof.
When properly made, this type of splice is equal or superior to the cable in strength and electrical properties. Contact Geokon for splicing materials and additional cable splicing instructions.
2.5 Lightning Protection The Model 6160 MEMS Tiltmeter, unlike numerous other types of instrumentation available from Geokon, does not have any integral lightning protection components, e.g., transzorbs or plasma surge arrestors. Usually this is not a problem. However, if the instrument cable is exposed, it may be advisable to install lightning protection components, as the transient could travel down the cable to the gauge and possibly destroy it.
3. TAKING READINGS 3.1 Dataloggers In most cases the 6160 and 6161 MEMS Tiltmeters will be monitored continuously and automatically using a Datalogger. Connections to the Geokon Model 8021 Micro-1000 Datalogger, which uses a Campbell Scientific CR1000 MCU are shown in Appendix D.
R is the current reading in volts is the reading at θ =zero zero G is the Gauge Factor shown on the calibration report for the Model 6160 tiltmeter. For measurements of tilt, i.e., changes of inclination, where R is the initial reading and R...
4.3 Environmental Factors Since the purpose of the inclinometer installation is to monitor site conditions, factors that may affect these conditions should be observed and recorded. Seemingly minor effects may have a real influence on the behavior of the structure being monitored and may give an early indication of potential problems.
5. TROUBLESHOOTING Maintenance and troubleshooting of the MEMS sensors used in the Model 6160 and 6161 Tiltmeters are confined to periodic checks of cable connections. The sensors are sealed and there are no user serviceable parts. Consult the following list of problems and possible solutions should difficulties arise. Consult the factory for additional troubleshooting help.
Polyurethane jacket, Foil shield, Polyurethane jacket, nominal OD = 7.9 mm Nominal OD = 6.3 mm Table 1 - Model 6160 and 6161 Tilt Sensor Specifications Notes: Depends on readout equipment. For best results requires a 4 ½ digit digital voltmeter.
APPENDIX B. THERMISTOR TEMPERATURE DERIVATION Thermistor Type: YSI 44005, Dale #1C3001-B3, Alpha #13A3001-B3 Resistance to Temperature Equation: − 273 2 A B LnR C LnR Equation 4 - Convert Thermistor Resistance to Temperature Where; T = Temperature in °C. LnR = Natural Log of Thermistor Resistance A = 1.4051 ×...
APPENDIX D. WIRING CODE Uniaxial MEMS with Connector Pin Connector Pin Biaxial MEMS 03-250V0 Designation Thermistor Designation without Thermistor cable 12VDC 12VDC Red’s Black Ground Ground White A Out Diff + A Out Diff + White’s Black A Out Diff - A Out Diff - Bare Shield...
APPENDIX E. 6160 STANDARD ADDRESSABLE SYSTEMS Description: The standard 6160 addressable system incorporates a Distributed Multiplexer Circuit Board that allows multiple MEMS type tiltmeters, uniaxial or biaxial, to be connected as “drops” off of a single bus. The tiltmeter “string” is addressed via ENABLE and CLOCK signals in the same manner as the Geokon Model 8032-16 Channel Multiplexer.
*1K and 5K precision resistors are used to complete the thermistor bridge circuit: Table 6 - Thermistor Bridge Circuit Specifications for Addressable System (Logic Level Style) Circuit Board: Board Dimensions: 4.5"(L) x 1.155"(W) x 0.4"(H) Power Requirements: +12V (± 3V) 110mA (max) when active 700uA (max) standby Operating Temperature:...
APPENDIX F. PROGRAMMING THE MEMS TILTMETER WITH CRBASIC Description: CRBASIC is the programming Language used with Campbell Scientific CRBASIC Dataloggers. Campbell’s LoggerNet Software is typically used when programming in CRBASIC. The MEMS sensor should be read with the VoltDiff instruction and the output averaged 100x. (No Thermistor in this example.) Sample Program: 'Declare Public Variables for Reading MEMS Sensor...
APPENDIX G. PROGRAMMING THE ADDRESSABLE MEMS TILTMETER WITH CRBASIC Description: CRBASIC is the programming Language used with Campbell Scientific CRBASIC Dataloggers. Campbell’s Loggernet Software is typically used when programming in CRBASIC. The MEMS sensor should be read with the VoltDiff instruction and the output averaged 100x. Sample Program: ‘The following sample program reads 20 addressable Bi-Axial MEMS Gauges and Thermistors.
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'counter for number of sensors For Channel = 1 To 20 '1st clock using C8 PortSet(8,1) Delay(0,10,MSEC) PortSet(8,0) Delay(0,10,MSEC) 'Delay Delay(0,100,mSec) 'Read the A-axis 'Reset the temporary storage location MEMS_3 = 0 'counter For MEMS_1 = 1 To 100 'differential voltage measurement on DIFF1 VoltDiff (MEMS_2,1,mV5000,1,False,0,1000,0.001,0) 'Sum the readings MEMS_3 = MEMS_3 + MEMS_2...
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'Calculate the Average reading value Reading_B = MEMS_3 / 100 'Delay Delay(0,100,msec) 'Read the thermistor 'half bridge measurement - SE5 AND EX1 BrHalf(THERM_1,1,mV2500,5,VX1,1,2500,0,1000,250,2.5,0.0) 'Calculate the temperature THERM_2 = THERM_1 / 5000 THERM_3 = (2.5 - (THERM_2*1000) - THERM_1)/THERM_2 Reading_THERM = 1/(.0014051 + (.0002369*LOG(THERM_3)) + (.0000001019*(LOG(THERM_3)^3))) - 273.2 '2nd clock using C8 PortSet(8,1)