Course GEOL-110:  Seismic survey, February 2008


O.M., 14 Feb. 2008
University of Bergen, Norway
Dept. of Earth Science

1. Instrumentation diagram




Fig. 1. Instrumentation diagram, GEOL-110, February 2008

2. Filter / Amplifier settings


3. Connection of Sparker

The sparker element has no polarity.
For the record: Boomer plate HAS polarity. Brown wire should go to Sparker Control Bank "positive" terminal (left on picture below). Boomer plates will  move in opposite direction (which is not desirable) if polarity is not correct.



Fig. 2. Connection of sparker. No polarity on sparker; on boomer connect "brown" wire to left terminal.

4. Grounding

Filter/amplifier and EPC plotter grounds should be connected to a common point.

Sparker ground lugs should be connected to ship's ground.


5. Sparker energy output

Ref. this picture from top of  Sparker Control Bank:



Fig. 3.  Selecting sparker capacitance


The wiring straps now divide the capacitance (expressed as energy - in Joules) into two sections. The one to the left is 300 + 100 + 100 Joule = 500 Joule.  The section to the right also represents 500 Joules.

The large switch will either short-circuit the section to the right, or include it in operation. As shown, the right capacitor section is short-circuited.


6. Spark gap cleaning


You might need to clean spark gap terminals:



Fig. 4. The spark gap terminals may need cleaning. Use abrasive paper sheets.

7. Sparker Cables

Referering to cable numbering in fig. 1, we use these cables:

7.1 Cable S1


Fig. 5. Sparker cable S1

We have two adapters  for this cable.


Fig. 6. Adapter A, for Sparker cable S1

If you use this cable, please note that fuses may blow on a 16 Amp power line that already supplies other equipment.


Fig. 7. Adapter B, for Sparker cable S1
 
The grey/blue connector can be purchased at Onninen, Minde. Part number is printed on connector lid.


7.2 Cable S2



Fig. 8. High-voltage cable between the two main sparker boxes.


7.3 Cable S3



Fig. 9. 115 Vac cable between transformer and sparker control unit.


8. Transformer 230 Vac to 115 Vac


Fig. 10. Transformer, 230 Vac to 115 Vac.


9. EPC Key output

The EPC "Key" output should be a positive pulse, in order to trigger the Sparker Control unit.

10. Pictures from 2007 survey