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Title

     HYA (Høyanger) upgrade, 2017

By
O.M.
Date
11 January, 2018
Version
0.1

1 HYA / HØYANGER UPGRADE, 19-20 DECEMBER, 2017


Sensor pit
Before: After:
Click to enlarge. Click to enlarge.
Telemetry, mains power, building 150 m from sensor pit
Before: After:
Click to enlarge.
Click to enlarge.
Click to enlarge.

2 PROCUREMENTS


Pos Qty Unit Supplier part no. Description
1 3 ea Mouser EIR2-EXTEND Ethernet Modules COPPER FOR 10/100 NETWORKS, VDSL2
2nd source: Digi-Key: EIR2-EXTEND, Ethernet Extenders
2 1 ea RS 508-2827 Fibox, PC 382818T, PC 82818T -- SOLID PC Polycarbonate Enclosure, IP66, IP67, 378 x 278 x 180mm
For use inside sensor box.
3 1 ea RS 188-2572 Fibox Mounting Plate for use with EK Series
Model: EKPVT, 338 x 238 ---- "Mounting plate, for enclosures: • 380x280x130, 380x280x180, 380x280x230, 560x380x180"
4 1 ea RS 508-2798 SOLID PC Polycarbonate Enclosure, IP66, IP67, 278 x 188 x 180mm
5 1 ea RS 188-2522 Fibox Mounting Plate for use with EK Series - model: EKJVT
      (1)          DC/DC-konverter

3 UPS


  • Manufacturer: APC
  • Model: BackUPS CS 650
  • Specifications
  • Connected loads:
    • GSM modem:
    • GSM SMS reset device
    • Seismometer / digitizer / power supply: Estimated 28 V x 0.482 A/0.8 = 17 Watt (efficiency factor: 0.8)
 POWER LOAD SUPPORTED BY UPS:
 ---------------------------
 Digi WR-21 modem ........................:  10 W
 Sikom GSM Mini ..........................:   5 W
 Seismometer, digitizer, power supply ....:  17 W
 ------------------------------------------------
 Total load (average) ....................:  32 W
                                             ====

According to manufacturer's runtime graph for this UPS model, a 40 Watt load should have 92.4 minute backup time, provided batteries are fully charged, and new. So 32 Watt load should have at least 90 minute backup time, when batteries are new, degrading perhaps to 30 minutes when batteries approach end-of-life state, after 5 years (these are estimates, at this stage).

4 NORTH ORIENTATION OF SENSOR


4.1 Using new fiber-optic gyro (FOG)


4.1.1 Instrument


  • Manufacturer: Teledyne Marine UK / TSS
  • Model: CDL TOGS
  • Datasheet (also local copy).
  • FOG instrument accuracy is 0.5 deg secant latitude RMS; that is, it has 0.5 deg RMS accuracy at the Equator, with heading error proportional to the inverse of the cosine of latitude. That means FOG heading accuracy at HYA latitude (61.16365N) is 1.04 deg RMS.

SPECIFICATIONS (from http://www.teledynemarine.com/cdl-togs):

4.1.2 Checkout procedure


Instrument checkout procedure, excerpt from manual p. 55:

4.1.3 Entering latitude value


By typing "menu", the FOG can be configured. We need to set latitude value. Confirmation:

  TOGS v1.4.0 - Main - Wed 20 Dec 2017 09:23:40
    Mode = 02 Status = 0
    1. Set initial latitude [61.164 deg]
    2. Set speed            [0.0 m/s]   
    3. Ports & strings                  
    4. Advanced                         
    5. Configuration dump               
    0. Back

This print-out confirms TOGS was given the correct latitude: 61.164 deg N

4.1.4 Telegram format


The TOGS-S outputs a Mode (‘mod’) and ‘hexadecimal’ Status Flag (‘erf’) information. The Operation Status Mode and definitions are listed in table below.

  -----------------------------------------------
  Mode   Meaning
  -----------------------------------------------
   0     Initial Power-On
   1     Coarse stationary alignment mode
   2     Fine stationary alignment mode
   3     Coarse stationary alignment mode w/GPS
   4     Fine stationary alignment mode w/GPS
   9     Aided navigation AHRS mode

Where the relevant telegram has this structure:

TOGS format:

  AHaaa.aa APbccc.cc ARdeee.ee Mf Ehhhhhhhhh Sg Ciiii<cr><lf>

  Where:
      aaa.aa is Heading in degrees decimal (0 to 359.99 deg)
      b [-] bow down / [+] stern down
      ccc.cc is Pitch in degrees decimal (-89.99 to 89.99 deg)
      d [-] port down / [+] starboard down
      eee.ee is Roll in degrees decimal (-179.99 to 179.99 deg)
      f is the TOGS-S IMU mode
      hhhhhhhhh is the cycle counter
      g is TOGS-S error status flags
      iiii CRC-16 checksum

Data file, 20 December 2017, captured during North alignment of new HYA BB sensor: HYA-North-alignment-FOG-20Dec2017.txt

Final telegrams, when alignment was complete:

  AH359.99 AP+000.77 AR-000.06 M9 E000053890 S0 CDFC4
  $HEHDT,359.9,T*29
  $HEROT,+000.0,A*00
  AH359.99 AP+000.77 AR-000.06 M9 E000053940 S0 CD3D9
  $HEHDT,359.9,T*29
  $HEROT,+000.0,A*00

4.2 If compass must be used


Fra: https://www.ngdc.noaa.gov/geomag-web/

4.3 Using sun's azimuth


5 ESTIMATE OF ORIGINAL SENSOR ORIENTATION


We are interested in determining the original sensor orientation when HYA 3-component station was established 4 May 1994, in order to rotate data records received in the period up to current modification, if orientation deviated much from that of geographic North.

Due to a misunderstanding, this issue was not deemed to be of such importance. So when original orientation was checked now, it was more to get an impression of what significance the new fiber-optic gyro could have in correcting orientation at other sites in the future. A different procedure would otherwise have been used in order to perform a thorough check on original sensor orientation.

ESTIMATE OF ORIGINAL SENSOR ORIENTATION
Click to enlarge.

Fig. 1: 19 Dec 2017 -- HYA, after opening sensor enclosure. Click to enlarge.

Click to enlarge.

Fig. 2: 19 Dec 2017 -- HYA, fiber-optic gyro being used to determine geographic North direction. Click to enlarge.

Click to enlarge.

Fig. 3: 19 Dec 2017 -- HYA, using compass to confirm fiber-optic North direction (blue line drawn on pit concrete). Expect to see 1.2 deg E deviation. To the right, zoomed version, with magnetic deviation shown. Click to enlarge.

Click to enlarge.

Fig. 4: 19 Dec 2017 -- HYA, expected 1.24 E +/- 0.44 deg deviation, provided fiber-optic compass yielded very accurate North orientation. (In fact, fiber-optic gyro measurement also has a specified accuracy, lightly above 1 deg RMS, at HYA latitude.) Click to enlarge.

Click to enlarge.

Fig. 5: 19 Dec 2017 -- HYA, compass aligned along sensor box side wall. Click to enlarge.

Click to enlarge.

Fig. 6: 19 Dec 2017 -- HYA, compass aligned along sensor box side wall, which is designated "N". Click to enlarge.

Click to enlarge.

Fig. 7: From NOOA online declination calculator, we obtain declination when HYA 3-component sensors was installed, 4 May, 1994.

5.1 Tentative conclusion


  1. Fig. 4 suggests that fiber-optic gyro shows correct geographic North orientation, as compass, when aligned on the new FOG North line, shows approx 1.9 deg E. Expected declination for HYA location as of 19 Dec 2017, is 1.24 E +/- 0.44 deg. FOG instrument accuracy is 0.5 deg secant latitude RMS; that is, it has 0.5 deg RMS accuracy at the Equator, with heading error proportional to the inverse of the cosine of latitude. That means FOG heading accuracy at HYA latitude (61.16365N) is 1.04 deg RMS.
  2. It is assumed that long side of sensor box was oriented North/South. We do not know if this is magnetic North, or if declination was taken into account - installation record does not show.
  3. Fig 6 shows that compass points 4.64 deg E, when it is aligned to long side of sensor box. Subtracting nominal declination of 1.2 deg E (as of December 2017), this means sensor box is oriented 3.44 deg W. When we read declination from NOAA online calculator, valid on date of sensor box installation (4 May 1994) we obtain 3.0 degrees W.
  4. This leads to the tentative conclusion that sensor box long side was oriented towards magnetic North during installation 4 May, 1995. Which implies that sensors were aligned 3 West, compared to geographic North, according to NOAA online mag. declination calculator.

6 WEATHER, ROAD CONDITIONS, AVALANCHE WARNINGS


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Page last modified on June 01, 2018, at 09:49 AM
Electronics workshop
Department of Earth Science - University of Bergen
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