Changes for page ANU Seismic Data Loggers

Last modified by robert on 2025/06/27 16:42

From version 40.2
edited by robert
on 2025/03/03 18:19
Change comment: There is no comment for this version
To version 48.1
edited by robert
on 2025/06/20 12:31
Change comment: There is no comment for this version

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3 3  ANU has designed and built three generations of seismic data recorders, two of which (the small yellow TerraSAWR and the larger beige LPR-200) are still in use today. Despite their contrasting appearance, they both use the same software, data cards, and have the same instrument response.
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11 +)))
5 5  
13 += Power Considerations =
14 +
15 +Both the LPR-200 (or "Low Power Recorder" 200) and TerraSAWR are designed to use as little power as possible, and more or less use the same amount of power.
16 +
17 +At 100 Hz and with a GPS cable connected these loggers draw about 220 mW of power once the screen is off. Adding a sensor (e.g. a Trillium Compact 120) increases this to approximately 400 mW, or 0.4 volt-amps. So, in theory 7 Ah battery should last about 10 days without a solar panel, but in practice it seems to be a bit closer to 8 which may be due to variability in power drain while in getting GPS locks.
18 +
19 +For very sunny environments (latitudes < 30) a 20V 10 Watt solar panel should have no issue keeping these loggers alive over the summer months, and assuming unobstructed skies should also be fine over winter. However there is no harm in using 20 or even a 40 Watt panel, especially for high latitudes, coastal regions, or areas without a full sky view. In theory up to a 60 Watt solar panel is fine, but we don't recommend anything over 40 Watts and that amount of power is already overkill.
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23 +Power issues are easy and cheap to solve relative to the cost of your experiment, don't skimp!
24 +)))
25 +
6 6  = Data Card Formatting and Information =
7 7  
8 8  Both the TerraSAWR and LPR-200 require SD Cards to be formatted in FAT32 filesystem. For 64Gb cards it can be difficult to format in FAT32, but [[software >>http://auspass.edu.au/field/fat32cardformatter.exe]]is available. ANU recommend SanDisk Extreme 150 mb/s cards in either 32 or 64Gb size. We strongly discourage using cards larger than 64Gb, and in general smaller cards are less likely to fail. We have also found that "adapter" cards (e.g. SD to microSD) are prone to having write issues and **strongly** advise against them.
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9 9  
10 10  The loggers can be "pre-programmed" with information (e.g. site name, sampling rate, etc) or they can be programmed in the field using the buttons on the logger. To pre-program the cards you simply edit a text file (named "[[ANUSRSetup.txt>>http://auspass.edu.au/field/ANUSRSetup.txt]]" for the LPRs, or "[[tSAWRSetup.txt>>http://auspass.edu.au/field/tSAWRSetup.txt]]" for the TerraSAWRs) and place it in the root directory on the SDCard. When the logger boots up, it will parse and load this information.
11 11  
12 -=== The format for ANUSRSetup.txt / LPR200s will be a single line of text that looks like this: ===
32 +== The format for ANUSRSetup.txt / LPR200s will be a single line of text that looks like this: ==
13 13  
14 14  {{{XXX195G0100010034864 2 }}}
15 15  
16 -corresponding to site XXX19,
17 - network 5G,
18 - sample rate 0100, (i.e. 100 Hz)
19 - "gps interval" 01 (once per hour~-~- don't change),
20 - start mode (always 0),
21 - stop mode (always 0),
22 - seismometer type (3 = broadband (+/- 20V), 2 = Guralp (+/- 10V), 1 = shortperiod (+/- 5V),
23 - and seismometer serial number (4864).
36 +//corresponding to//
24 24  
38 + site **XXX19**,
39 + network **5G**,
40 + sample rate **0100**, (i.e. 100 Hz)
41 + "gps interval" **01** (once per hour~-~- don't change),
42 + start mode (always **0**),
43 + stop mode (always **0**),
44 + seismometer type (**3** = broadband (+/- 20V), 2 = Guralp (+/- 10V), 1 = shortperiod (+/- 5V),
45 + and seismometer serial number (**4864**).
46 +
25 25  (% class="box warningmessage" %)
26 26  (((
27 27  NOTE: the 2 at the very end is for "RECORD ON RESTART". The record on restart option ensures that if the logger dies and is powered back up whilst in the field (due to battery charging cycles or other causes) that the recording will resume. (# of blank spaces before this doesn't matter)
28 28  )))
29 29  
30 -=== The format for TSAWR loggers is shorter: ===
52 +== The format for TSAWR loggers is shorter: ==
31 31  
32 32  (% class="box errormessage" %)
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46 46   and seismometer serial number (9999).
47 47  
48 48  
49 -=== The formatting process using the logger: ===
71 +== The formatting process using the logger: ==
50 50  
51 51  The process for formatting an SD card within the logger is straightforward. Navigate to the "SD INFORMATION" screen and press ERASE SD CARD. This process may take up to a minute. This will result in erasing all files from the card. Upon starting recording, a new 'seed' will be written containing all the information that the logger has been set with FINISH THIS SECTION
52 52  
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58 58   32Gb card: 122 days @ 250hz or 305 days @ 100hz
59 59  }}}
60 60  
83 +== Default Settings ==
61 61  
85 +As of 2025, the default settings for both LPR (v. 2.7) and TSWAR (v 3.6a) loggers are below. If you're using a broadband instrument, you are essentially good to go without having to program the cards.
86 +
87 +* XX.ANUSR network and station name
88 +* 100 Hz Sample Rate
89 +* 40V pp (or +/- 20 V) gain / Trillium Compact seismometer version
90 +* Record on Restart enabled
91 +
92 +Note that if a user sets the gain incorrectly, this can be fixed later (assuming nothing clipped) by multiplying or dividing by factors of 2. The gain setting can be looked up from the logfile, else you may have to guess from a PSD or other method.
93 +
62 62  = Logger Menus Overview (and setup) =
63 63  
64 64  The same menus are used in both the TSAWR and LPR-200 loggers.
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69 69  
70 70  This menu also displays the firmware version, battery, external, and solar voltages, and the temperature of the system.
71 71  
72 -==== Upon setup ====
104 +* Check all Initialisation Parameters are marked as successful.
105 +* Check that solar voltage is above 10 V, otherwise the station will not last long.
73 73  
74 -- Check all Initialisation Parameters are marked as successful.
75 -
76 -- Check that solar voltage is above 10 V, otherwise the station will not last long.
77 -
78 -
79 79  == Live Seismometer Data ==
80 80  
81 81  This screen displays real time seismometer data for all 3 axes of the seismometer. Initially, a plot of raw data from all 3 channels is shown. By pressing enter, a high pass filter can be applied showing a more useful plot of all channels. The up and down arrows can be used to change between a view of all channels, individual channels, and all channels on different X axes.
82 82  
83 -==== Upon setup ====
111 +* Check that all 3 channels are present and are producing a signal.
112 +* Stomp on the ground near where the sensor is installed to check that a signal is being picked up by all 3 channels.
113 +* Common representations of poor signals include channels sloping smoothly from high values to zero, or sharp corners in the plots.
84 84  
85 -- Check that all 3 channels are present and are producing a signal.
86 -
87 -- Stomp on the ground near where the sensor is installed to check that a signal is being picked up by all 3 channels.
88 -
89 -- Common representations of poor signals include channels sloping smoothly from high values to zero, or sharp corners in the plots.
90 -
91 -
92 92  == GPS Data ==
93 93  
94 94  This menu displays the status of the stations' GPS connection. The screen lists; UTC time, UTC date, latitude, longitude, altitude, number of satellite connections, and SNR.
95 95  
96 -==== Upon setup ====
119 +* Check that the station is connected to satellites
97 97  
98 -- Check that the station is connected to satellites
99 -
100 -
101 101  == SD Information ==
102 102  
103 103  The menu lists if the SD card has been initialised, as well as the capacity and space free on the memory card. See "Data card formatting" (above) to see how to format and initialise the inserted SD card.
104 104  
105 -
106 106  == System Configuration ==
107 107  
108 108  This menu is used to set the stations identifiers and parameters.
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115 115  
116 116  The seismometer model and serial number (up to 10 characters) can be set. Seismometer model options include:
117 117  
118 -- Trillium Compact
137 +* Trillium Compact (same for 20 and 120)
138 +* CMG - 3ESP
139 +* Guralp 40T
140 +* LE-3D Lite
141 +* Mark L4C
142 +* Mark L4
119 119  
120 -- CMG - 3ESP
121 -
122 -- Guralp 40T
123 -
124 -- LE-3D Lite
125 -
126 -- Mark L4C
127 -
128 -- Mark L4
129 -
130 130  Additionally, the following settings can be used in place of the seismometer model types: +/- 20V, +/- 10V, +/- 5V
131 131  
132 132  The record on restart option ensures that if the logger dies and is powered back up whilst in the field (due to battery charging cycles or other causes) that the recording will resume.
133 133  
134 -==== Upon setup ====
148 +* Set the sampling rate, station identifier, and network code. Set the appropriate seismometer type. Most importantly, ensure the record on restart setting is checked.
135 135  
136 -- Set the sampling rate, station identifier, and network code. Set the appropriate seismometer type. Most importantly, ensure the record on restart setting is checked.
137 -
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139 139  (((
140 140  NOTE: Ensure the 'RECORD ON RESTART' option is marked with a cross.
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145 145  
146 146  == STA/LTA Configuration ==
147 147  
148 -The Short Term Average and Long Term Average Configuration screen is no longer used.
160 +The Short Term Average and Long Term Average Configuration screen.. this is a relic for when people weren't recording continuously. Not advised!
149 149  
150 -
151 151  = LogFile Conversion Script =
152 152  
153 153  Both the TSAWR and LPR-200 write logging information as a binary "dat" file which includes GPS time syncs, temperatures, battery power, and position. To convert them into ASCII you can read, use [[THIS PYTHON SCRIPT>>http://auspass.edu.au/field/anusr_log.py]].
154 154  
155 -
156 156  = Instrument Response =
157 157  
158 -Both the TerraSAWR and LPR-200 use the same ADS1281 analog-to-digital converter chip and are designed to have identical instrument response. Depending on the output sample rate (e.g. 100 Hz, 250 Hz, 500 Hz, 1000 Hz) amplitude response is consistently flat up to ~~100 Hz but phase response can vary above 1 Hz at 100 Hz (or 10 Hz at 250 Hz).
168 +Both the TerraSAWR and LPR-200 use the same ADS1281 analog-to-digital converter chip and are designed to have identical instrument response. Depending on the output sample rate (e.g. 100 Hz, 250 Hz, 1000 Hz) amplitude response is consistently flat up to ~~100 Hz but phase response can vary above 1 Hz at 100 Hz (or 10 Hz at 250 Hz).
159 159  
160 160  The user can choose to apply a 2nd stage "sensor gain" by selecting an instrument type in the setup menu. This effectively selects a 10 Vpp (e.g. short period sensors), 20 Vpp, 40 Vpp (most broadband sensors) regime to match the sensor's sensitivity. This has the effect of doubling amplitude from 10v to 20v, or quadrupling from 10v to 40v. If you have set your sensor correctly (and the signal isn't clipped!) you can "correct" this by simply multiplying your data by 0.5 etc.
161 161  
162 162  Another important thing to note is that the group delay associated with late stage FIR filters is **automatically applied in the logger**, hence there is no need to apply this in the response. These tend to max out at 0.124 seconds for most output sampling rates (0.062 s for 100 Hz).
163 163  
164 -Instrument response can be downloaded from IRIS-NRL (v2) if need be, or by downloading the response of an equivalent sensor at AusPass (e.g. get_stations(level='response') )
174 +Instrument response can be downloaded from IRIS [[Nominal Response Library>>https://ds.iris.edu/ds/nrl/]] if need be, or [[directly from us>>http://auspass.edu.au/data/logger_response]] , or by downloading the response of an equivalent sensor at AusPass (e.g. get_stations(level='response') ).
165 165  
176 +The response info from IRIS-NRL is the "full" version which (in theory!) perfectly describes the data logger's bias on the data. However this is in many way overkill and at the cost of 1) increased metadata size and, more importantly, 2) increased CPU demand in the response removal process. Testing has shown that for signals below 100 Hz, the "full" response offers little to no benefit and can increase the time it takes to remove the response for a 1 hour window of 100Hz data by a factor of x20 or more. For earthquake arrival data this is often negligible, but for data intensive tasks like ambient noise cross-correlations this can be a severe hindrance. Thus we have created a parallel version of this response which removes the SINC and FIR filters completely. These are labelled "fast" in our [[local response archive>>http://auspass.edu.au/data/logger_response]] and essentially truncate response stages 3 onwards into a "fake" decimation step from 1024000 Hz to the desired output samplerate with no filtering whatsoever.
166 166  
167 -= ANU TerraSAWR (Gen 3, FW 3.5a, 2017?- current) =
178 +In the below we show both responses applied to a test signal with a frequency range of 1000 seconds to 100 Hz. The maximum discrepancy in signal is less than 0.01% (1.0001) which is far below what you should expect from the mechanical inconsistencies intrinsic to the sensor itself. Thus, we strongly advise users employ the "fast" version of this response information and it is what we use for our networks by default. If you are recording at 1000 Hz, or care deeply about signals above 100 Hz (so recorded at 250 or 1000 Hz), please use the full response. Any questions, please ask!
168 168  
169 -Text here
180 +[[Testing the "full" and "fast" versions of the ANU data logger response on synthetic 250 Hz data from 1000 seconds to 100 hertz. For all intents and purposes, they are identical.>>image:full_vs_fast.png||data-xwiki-image-style-alignment="center"]]
170 170  
171 -== Sub-paragraph ==
172 172  
173 -XXXX
183 += ANU TerraSAWR (Gen 3, FW 3.5a, 2017- current) =
174 174  
175 -== Sub-paragraph ==
185 +Not sure there's much left to say
176 176  
177 -xx
178 178  
179 179  
180 -
181 -
182 182  = ANU LPR-200 (Gen 2, FW 2.6a/2.7a, 2013 - current) =
183 183  
184 -Text here
191 +Ditto the mighty LPR!
185 185  
186 -== Sub-paragraph ==
187 187  
188 -x
194 += ANU "ANUSR" (Gen 1, 2003? - 2012) =
189 189  
196 +This logger has been retired for a long time and has a different instrument response. It used modular component boards and was powered via an acrylic case of 6 x 6V lantern batteries. There is a somewhat complete one above the CAT lab door if anyone is so inclined to have a look.
190 190  
191 191  
192 -= ANU "ANUSR" (Gen 1, 2003? - 2013?) =
193 -
194 -x
195 -
196 196  = References =
197 197  
198 198  * [[PDF Manual>>http://auspass.edu.au/field/LPR-200_Instruction_Manual.pdf]]
199 -~)~)~)
202 +)))
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202 202  (((
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208 208  )))
209 209  
210 210  
214 +
215 +
216 +
217 +
211 211  (% class="box" %)
212 212  (((
213 213  = TerraSAWR Specs =
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220 220  [[image:1704864886951-793.jpg]]
221 221  
222 222  |=Size (L x W x H)|30 x 25 x12cm
223 -|=Weight (with battery)| ~*~*1.9kg (2.5kg)
230 +|=Weight (with battery)| 1.9kg (2.5kg)
224 224  |=Battery|(((
225 -Lead-acid 12v, ~~7Ah
232 +Lead-acid 12v, ~~7-9Ah
226 226  
227 227  Rechargeable
228 228  )))
236 +|=Current Firmware|3.5a (Jan 2025)
229 229  
230 230  [[image:terrasawr battery.jpg]]
231 231  )))
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242 242  [[image:LPR 3.jpg]]
243 243  
244 244  |=Size (L x W x H)|42 x 34 x17 cm
245 -|=Weight (with battery)|4.9 kg (7.3 kg)
253 +|=Weight (no battery)|5.5 kg
246 246  |=Battery|(((
247 -LiFePo4 140Ah
255 +NOW: Any 12v battery with tab connections that will fit (ex. the same TSAWR battery)
248 248  
249 -Rechargeable
257 +DISCONTINUED: LiFePo4 140Ah Rechargeable (shown below).
250 250  )))
259 +|=Current Firmware|(((
260 +2.6a (old GPS modules) / 2.7a
251 251  
262 +Jan 2025
263 +)))
264 +
252 252  [[image:LPR battery.jpg]]
253 253  )))
254 254  )))
255 -
256 -~)~)~)
268 +)))
full_vs_fast.png
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