Geospace GSB, User Manual

Page 1: ... Manual GSB User Manual 593 01940 01 Rev C release date TBD Page 1 of 27 GSB User Manual Geospace Technologies Corporation 7007 Pinemont Drive Houston TX 77040 TEL 713 986 4444 FAX 713 986 4447 www geospace com ...

Page 2: ...ge or computer language in any form or by any means electronic manual or otherwise without written permission of Geospace Technologies Corporation 7007 Pinemont Drive Houston Texas 77040 U S A Copyright violators may be subject to civil penalties DISCLAIMER Geospace Technologies Corporation makes no warranties as to the accuracy validity or fitness for use of the contents of this Manual Geospace T...

Page 3: ...leep mode 8 3 3 Disabled mode 8 3 4 Search lost device mode 8 3 5 Powered off 8 4 Field operation instructions 9 4 1 Deploying GSBs 9 4 2 Picking up GSBs 13 4 3 GSB LED flash codes 15 4 4 LineViewer LHR LHV operations 16 4 5 Extended operation time 17 4 6 Charge of internal battery 18 4 7 Preparing GSBs for storage or shipment 19 5 GSB test 20 5 1 Instrument test 21 5 2 Sensor test 24 6 Attachment...

Page 4: ...124 dB instantaneous dynamic range Battery life 60 days 24 hours day operation for 1 channel devices or 40 days for 3 channels A low power option is available for GSB 3s to increase operation time Record time can be extended by connecting an external battery or a solar panel Built in full resolution test signal generator Solid state flash memory 16 or 32 GB 115 230 days at 2 ms SR per channel No a...

Page 5: ...ays of deployment Light weight 1 Kg 1 or 3 channels models 2 GSB data downloader and charger The GSB racks provide an interface to download data and charge the internal battery The racks are 12 slots modular There are two types of racks available to be used with the GSBs Portable for small crew operation or to be used in remote sites GSB trailer for normal operations 2 1 Portable chargers and data...

Page 6: ...mer s request each module can charge the internal battery and retrieve seismic data from up to 60 GSBs simultaneously A trailer with 8 modules 480 slots can charge approximately 2000 GSBs per days Vertical racks can also be installed in containers or any warehouse 3 GSB operational modes The operational modes for the GSB are Record mode Recording seismic data ...

Page 7: ...SP position accuracy and display a SOS pattern in the LED Powered off All GSB circuitry is turned off It is set when devices are programmed to storage or shipping mode 3 1 Record mode This is the normal operation mode in the field when the GSBs are recording seismic data To be in this mode the desired recording hours should be programmed using parameters set in GeoReaper To enter into record mode ...

Page 8: ... this mode the GSB searches for GPS for 15 minutes to get an accurate position while showing a SOS LED pattern It helps to improve its location if the device is recording or to find a disabled device lost in the field To put a device in this mode the user should use the LHR LHV combo to perform the Find Lost Device operation If you are searching for a lost GSB that has not been deployed yet you ne...

Page 9: ...conds and then turns off 4 Field operation instructions When the GSBs are removed from the rack they immediately go to disabled mode radio channel for communication is programmed to channel 1 In this mode the GSB LED shows two quick flashes every 10 seconds see section 4 3 for detailed LED flash codes descriptions 4 1 Deploying GSBs To deploy GSBs to start recording seismic data follow the next st...

Page 10: ...of 27 B Put the GSB in record mode a Hold the GSB from the geophone side and keep it as vertical as possible see notes at the end of this section b Observe that the GSB LED goes to an intermediate state where the LED flashes for one second on followed by one second off pattern ...

Page 11: ...ent sequence running geophone tests LED flash rapidly 5 times a second If the GSB is still showing sleep mode because the angle on step B was incorrect restart the sequence F Wait until the GSB is in recording mode one quick flash every 8 seconds for recording with GPS off or LED two quick flashes once per second for GPS on with GPS fix It continues to record until device is sent to disabled mode ...

Page 12: ...GSB User Manual GSB User Manual 593 01940 01 Rev C release date TBD Page 12 of 27 Notes GSB power connector up Tilt 0 to 20 for deployment GSB flat tilt of 90 20 ...

Page 13: ... Picking up GSBs To pick GSBs properly from the spread follow the next steps A Hold the GSB from the battery side and keep it as vertical as possible B Wait for the LED turns on about 10 seconds C Put the device plate up on the surface After about 2 seconds the GSB goes to disabled mode ...

Page 14: ...from the spread while is disabled the LED blinks twice every 10 seconds indicating a disabled state F To Transport GSBs is recommended to grab them from the geophone side to avoid going to the pre deploy mode Note If the GSB is not set to disabled mode it could generate extra segments of data while it is being moved to a different location ...

Page 15: ...ritical GSR Error LED flashes repeatedly on solid for 1 second followed by off for one second Critical Geophone 1 Error LED on solid for 1 second followed by 1 short pulse Critical Geophone 2 Error LED on solid for 1 second followed by 2 short pulses Critical Geophone 3 Error LED on solid for 1 second followed by 3 short pulses Critical Geophone 4 Error LED on solid for 1 second followed by 4 shor...

Page 16: ...iewers and LHRs get statuses from GSBs via radio LVs should have the script version 2 0 from GeoReaper loaded to allow a QC evaluation that includes Parameters checksum The GSBs have inclinometers to allow measuring the angle of the case vs gravity vector as follows Tilt information may be read in QC devices Using Line Viewer ...

Page 17: ...TBD Page 17 of 27 Using LHV LHR 4 5 Extended operation time The GSB recording hours may be extended connecting an external battery or a solar panel Using an external battery the GSB gets the power from the external battery first and then switches to the internal one ...

Page 18: ...nternal battery is performed when the device is connected to the rack The GSBs may be programmed to start the charging process as soon they are connected to the rack no need of external commands The charge of the battery requires 1 hour for every 10 days of field recording time The process of charging starts feeding the battery with a constant current of 4 2 Amperes up to the time when the nominal...

Page 19: ...rt industry regulations Geospace recommends setting the batteries to 60 or 30 of their capacities respectively This operation is performed upon GeoReaper command When the GSBs are set to 60 or 30 they use the measured voltage to estimate the actual capacities of the batteries The following situations can occur If the capacity is higher than the programmed limit the GSB enters a turn everything on ...

Page 20: ...ey must be reconnected to the GSB rack The GSBs are not required to go fully charge or discharge the battery for initial evaluation of the capacities The software uses the measured battery voltages to determine their capacities 5 GSB test Geospace provides different techniques to confirm the proper performance of GSBs when they are connected to the server or via radio in field operations When they...

Page 21: ...st specifications are in Table 1 Table 1 GSB THD Instrument Test Gain Accuracy The gain accuracy test confirms that the gain calibration applied by the channel yields the proper DC value The test uses the internal test oscillator to measure the various gain steps in a series of 21 measurements The first record measures a full scale test oscillator reference DC signal through the output circuitry a...

Page 22: ...cond record sets the input switches to the test oscillator position and the test oscillator is set to run at 31 25Hz at full scale and is used to compute the RMS value of the full scale data The ratio of RMS value of the full scale data to noise is computed to yield the dynamic range of the data channel Test specifications are in Table 3 Table 3 GSB Dynamic Range Instrument Test Impulse The impuls...

Page 23: ... of the channel samples The DC offset value is removed from the data samples before computing the RMS value to get the equivalent input noise Test specifications are in Table 4 Table 4 GSB Noise Instrument Test Impedance The input switches are connected to the test oscillator A sinusoidal signal of 15 625 Hz is generated at 90 of full amplitude to give a reference measurement of 2048 samples A sec...

Page 24: ... of 31 25 Hz sinusoidal wave at 55 of full amplitude A data record is acquired for analysis The dB Vrms value is computed for each channel Parameter specifications are in Table 6 Table 6 GSB CMRR Instrument Test 5 2 Sensor test The GSBs automatically perform sensor tests when they are deployed or any time programmed by the user during the day or by QC device command The sensor tests are Sensor Imp...

Page 25: ...s common to both input pins Results may be affected by leakage bad sensors and high ambient noise To perform CMRR test the GSB test signal generator provides a sine wave of known amplitude 90 of full scale and frequency selected by user to both analog pins and evaluates the ratio of the RMS value of the output voltage vs the ADC input A comparison vs maximum ratio selected by user provides a pass ...

Page 26: ...GSB User Manual GSB User Manual 593 01940 01 Rev C release date TBD Page 26 of 27 6 Attachments 6 1 GSB 1 specifications ...

Page 27: ...GSB User Manual GSB User Manual 593 01940 01 Rev C release date TBD Page 27 of 27 6 2 GSB 3 specifications ...