Geokon RB-500 User manual

Instruction Manual
Model RB-500
MEMS Sensor Readout Box
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 © 2005-2019 by Geokon®
(Doc Rev J, 05/01/19)

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. INCLINATION MEASUREMENT ...................................................................................................................... 2
2.1 DATA INTERPRETATION ....................................................................................................................................... 3
2.2 READING TEMPERATURE ..................................................................................................................................... 3
3. MAINTENANCE.................................................................................................................................................... 4
3.1 GENERAL MAINTENANCE .................................................................................................................................... 4
3.2 CALIBRATION ...................................................................................................................................................... 4
3.3 BATTERY CHARGING ........................................................................................................................................... 4
4. TROUBLE SHOOTING ........................................................................................................................................ 5
APPENDIX A. SPECIFICATIONS .......................................................................................................................... 6
A.1 RB-500 SPECIFICATIONS .................................................................................................................................... 6
A.2 THERMISTOR (INSTALLED IN MEMS SENSOR).................................................................................................... 6
APPENDIX B. THERMISTOR TEMPERATURE DERIVATION ...................................................................... 7
APPENDIX C. EXAMPLE CALIBRATION SHEET ............................................................................................ 8
FIGURES
FIGURE 1-SAMPLE CALIBRATION SHEET...................................................................................................................... 8
TABLES
TABLE 1-WIRING CHART ............................................................................................................................................. 2
TABLE 2-SPECIFICATIONS ............................................................................................................................................ 6
TABLE 3-THERMISTOR RESISTANCE VERSUS TEMPERATURE ....................................................................................... 7
EQUATIONS
EQUATION 1-TILT CALCULATION ................................................................................................................................ 3
EQUATION 2-RESISTANCE TO TEMPERATURE .............................................................................................................. 7

1
1. INTRODUCTION
The Geokon Model RB-500 MEMS (Micro Electro Mechanical Structure) Sensor Readout Box
is a portable battery powered instrument for reading the voltage output from the Geokon 6150
and 6155 MEMS In Place Inclinometers, the Geokon 6160 MEMS tilt sensors, and the Model
6101 Portable Tiltmeter.
The Readout Box incorporates a 12 volt, 1.2 Ahr Lead acid battery, a 4½ digit liquid crystal
display (LCD), a power on/off switch, an A/B selector switch, a battery charger circuit, an AC
adaptor connector, and a 10-pin Bendix connector and a terminal strip.
The RB-500 instrument supplies +12V power to the MEMS sensor and displays the output in
Volts which is proportional to the sine of the angle of inclination.

2
2. INCLINATION MEASUREMENT
Complete the following steps:
1) Connect the MEMS Sensor to the readout box by means of the 10-pin plug or, if bare leads,
by means of the terminal strip on the face panel following the printed color code on the
panel.
Wire Color
Description
RED
+12V Power
RED’S BLACK
GROUND
WHITE
Channel A +Voltage Output
WHITE’S BLACK
Channel A –Voltage Output
SHIELD
Cable overall shield
GREEN
Uniaxial sensors: Thermistor +
Biaxial sensors: Channel B +Voltage Output
GREEN’S BLACK
Uniaxial sensors: Thermistor –
Biaxial sensors: Channel B –Voltage Output
BLUE
Biaxial sensors: Thermistor +
BLUE’S BLACK
Biaxial sensors: Thermistor –
Table 1 - Wiring Chart
Warning! Do not allow the RED and RED’S BLACK leads to touch each other, if the
leads do touch each other it will blow the internal 0.6A Slo-Blo fuse. Additional fuses are
supplied with the readout box.
2) Switch the power switch to the "ON" position.
3) Switch the selector switch to the "A" position.
4) Read the display and record the reading.
5) If a Biaxial sensor is connected, switch the selector switch to the “B” position.
6) Read the display and record the reading.
7) Power the unit off with the "OFF" switch.

3
2.1 Data Interpretation
The calculated Tilt is derived from the equation:
Tilt = (R1– R0)G
Equation 1 - Tilt Calculation
Where;
G = The gauge factor, (sin θ/volt) or (degrees/volt) from the calibration report provided with the
sensor. (A sample calibration report is provided in Appendix C.)
R0= The initial reading in volts as displayed on the RB-500
R1= The current readings in volts as displayed on the RB-500.
2.2 Reading Temperature
The RB-500 does not read temperatures.
The thermistor built into the sensor gives a varying resistance output as the temperature changes.
To read the thermistor using an ohmmeter, complete the following:
1) Connect the ohmmeter to the two thermistor leads (refer to Table 1). Since the resistance
changes with temperature are large, the effect of cable resistance is usually insignificant. For
long cables a correction can be applied, equal to approximately 14.7Ωfor every 1000 ft., or
48.5Ωper km at 20 °C. Multiply these factors by two to account for both directions.
2) Look up the temperature for the measured resistance in Table 3 in Appendix B

4
3. MAINTENANCE
3.1 General Maintenance
Keep the following points in mind when using the RB-500 MEMS Sensor Readout to maximize
reliability and accuracy of the unit.
•The readout box is splash proof, but it will not withstand complete immersion in water.
•The face plate should be kept clean and dry and the box should be stored in a warm dry area
when not in use.
•The transducer connector is waterproof.
•The battery charger connector is not waterproof.
•In very wet or humid conditions, the connector should be kept sealed using the plug
provided.
•Do not spray oil or WD40 into the connections. If they become wet, they must be dried
prior to use or errors will likely result. Clean the connections with soap and water and dry
thoroughly before use.
3.2 Calibration
The readout should be sent periodically (every 12 months) back to the manufacturer for
inspection, cleaning, and calibration. A nominal fee will be charged for the service, but it is
highly recommended.
3.3 Battery Charging
Battery charging is accomplished by plugging the AC adapter provided into the 3-pin connector
on the readout box face plate and into the 120 VAC mains (230 VAC adaptor also available).
The charger is automatic and can be left connected to the battery indefinitely. This will preserve
the maximum charge condition with no danger to the battery.
CAUTION: Lead acid batteries are good in that they do not have the memory effect of Ni-Cad
batteries. However, they do suffer from the disadvantage that they do not always recover from a
deep discharge if the battery is allowed to go absolutely flat or dead. It is important, if the battery
is not to be used for an extended period, that the charger be left plugged in. Also, avoid draining
the battery completely.

5
4. TROUBLE SHOOTING
If the readout box fails to put out any power, it may be because the 12-volt power lead was
inadvertently shorted to ground. To check, remove the face plate and replace the 6/10 Amp fuse
to be found in the fuse holder. Additional fuses are included with a new readout box. If the
readout box fails to power up it may be that the internal two-amp fuse has blown. This fuse
protects the battery in case of major internal malfunction. Additional fuses are included with a
new box.

6
APPENDIX A. SPECIFICATIONS
A.1 RB-500 Specifications
Range:
±4.000 Volts input.
Resolution:
100µV
Accuracy:
±0.06%
Power Requirements:
12 VDC @ 50 mA
Battery Type:
Lead acid 12 volt, 1.2 Ahr
Operating Time:
≈24 hours
AC Adaptor:
120 VAC: 50-60 Hz, 18 VDC, 533 mA
230 VAC: 50-60 Hz, 15 VDC, 800 mA
Dimensions:
6.5 ×4 ×8.5", 165 ×102 ×216 mm
Weight:
5 lbs., 2.3 kg.
Materials:
Aluminum case and lid
Operating Temperature:
-20 to +120° F, -30 to +50° C
Display:
4½ digit LCD
Input connection:
Bulkhead: Bendix PTO2A-12-10S
Mating: Bendix PY06A-12-10P(SR)
Fuse
Two 2A Slo-Blo (Geokon p/n ELC-412)
One 0.6A Slo-Blo (Geokon p/n ELC-104)
Charger connection:
Bulkhead: Lemo EGG OK 303 CNL(N&W)
Mating: Lemo FGG OK 303 CNA C/3.7
Table 2 - Specifications
A.2 Thermistor (Installed in MEMS Sensor)
(see Appendix B also)
Range: -80 to +150° C
Accuracy: ±0.5° C

7
APPENDIX B. THERMISTOR TEMPERATURE DERIVATION
Thermistor Type: YSI 44005, Dale #1C3001-B3, Alpha #13A3001-B3
Resistance to Temperature Equation:
T= 1
A+B(LnR)+C(LnR)3-273.15 °C
Equation 2 - Resistance to Temperature
Where;
T =Temperature in °C.
LnR =Natural Log of Thermistor Resistance.
A =1.4051 ×10-3 (coefficients calculated over the −50 to +150°C. span)
B =2.369 ×10-4
C =1.019 ×10-7
Ohms
Temp
Ohms
Temp
Ohms
Temp
Ohms
Temp
Ohms
Temp
201.1K
-50
16.60K
-10
2417
+30
525.4
+70
153.2
+110
187.3K
-49
15.72K
-9
2317
31
507.8
71
149.0
111
174.5K
-48
14.90K
-8
2221
32
490.9
72
145.0
112
162.7K
-47
14.12K
-7
2130
33
474.7
73
141.1
113
151.7K
-46
13.39K
-6
2042
34
459.0
74
137.2
114
141.6K
-45
12.70K
-5
1959
35
444.0
75
133.6
115
132.2K
-44
12.05K
-4
1880
36
429.5
76
130.0
116
123.5K
-43
11.44K
-3
1805
37
415.6
77
126.5
117
115.4K
-42
10.86K
-2
1733
38
402.2
78
123.2
118
107.9K
-41
10.31K
-1
1664
39
389.3
79
119.9
119
101.0K
-40
9796
0
1598
40
376.9
80
116.8
120
94.48K
-39
9310
+1
1535
41
364.9
81
113.8
121
88.46K
-38
8851
2
1475
42
353.4
82
110.8
122
82.87K
-37
8417
3
1418
43
342.2
83
107.9
123
77.66K
-36
8006
4
1363
44
331.5
84
105.2
124
72.81K
-35
7618
5
1310
45
321.2
85
102.5
125
68.30K
-34
7252
6
1260
46
311.3
86
99.9
126
64.09K
-33
6905
7
1212
47
301.7
87
97.3
127
60.17K
-32
6576
8
1167
48
292.4
88
94.9
128
56.51K
-31
6265
9
1123
49
283.5
89
92.5
129
53.10K
-30
5971
10
1081
50
274.9
90
90.2
130
49.91K
-29
5692
11
1040
51
266.6
91
87.9
131
46.94K
-28
5427
12
1002
52
258.6
92
85.7
132
44.16K
-27
5177
13
965.0
53
250.9
93
83.6
133
41.56K
-26
4939
14
929.6
54
243.4
94
81.6
134
39.13K
-25
4714
15
895.8
55
236.2
95
79.6
135
36.86K
-24
4500
16
863.3
56
229.3
96
77.6
136
34.73K
-23
4297
17
832.2
57
222.6
97
75.8
137
32.74K
-22
4105
18
802.3
58
216.1
98
73.9
138
30.87K
-21
3922
19
773.7
59
209.8
99
72.2
139
29.13K
-20
3748
20
746.3
60
203.8
100
70.4
140
27.49K
-19
3583
21
719.9
61
197.9
101
68.8
141
25.95K
-18
3426
22
694.7
62
192.2
102
67.1
142
24.51K
-17
3277
23
670.4
63
186.8
103
65.5
143
23.16K
-16
3135
24
647.1
64
181.5
104
64.0
144
21.89K
-15
3000
25
624.7
65
176.4
105
62.5
145
20.70K
-14
2872
26
603.3
66
171.4
106
61.1
146
19.58K
-13
2750
27
582.6
67
166.7
107
59.6
147
18.52K
-12
2633
28
562.8
68
162.0
108
58.3
148
17.53K
-11
2523
29
543.7
69
157.6
109
56.8
149
Table 3 - Thermistor Resistance versus Temperature
55.6
150

8
APPENDIX C. EXAMPLE CALIBRATION SHEET
Figure 1 - Sample Calibration Sheet