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Bartington Grad601 Operation manual

Manual is about: Single Axis Magnetic Field Gradiometer System

Summary of Grad601

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    Operation manual for grad601 single axis magnetic field gradiometer system.

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    Bartington instruments page 3 of 61 om1800/26 table of contents list of figures 6 1. About this manual 7 1.1. Symbols glossary 7 1.2 typography and units 7 2. Safe use 7 3. General description 8 4. Battery cassette and charger 11 4.1. Charging the battery 11 4.2. Changing the battery 12 4.3. Shippin...

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    Bartington instruments page 4 of 61 om1800/26 15.3. Error measurement 25 15.4. Adjustment 26 16. Scan mode (grid mode) / run mode (nmea mode) 28 17. Survey mode (grid mode) 29 17.1. Survey parameters 29 17.2. Single and multiple sensors 30 17.3. Surveying at 1 line/m 35 17.4. Surveying at 2 or 4 lin...

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    Bartington instruments page 5 of 61 om1800/26 a.4. Grids, lines and positions 56 a.5. Survey methods 56 a.6. Equipment required 56 a.7. Setting out the area 57 a.8. Setting up the gradiometer 57 a.9. Logging data 57 a.10. Other methods 58 notes 59.

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    Bartington instruments page 6 of 61 om1800/26 list of figures figure 1: grad-01-1000l identification label 8 figure 2: grad601-2 dual sensor gradiometer arrangement with harness 9 figure 3: grad601-1 single sensor gradiometer arrangement 9 figure 4a: bc601 battery cassette & charger 11 figure 4b: bc...

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    Bartington instruments page 7 of 61 om1800/26 1. About this manual this document describes the installation, function, testing, operation and maintenance of the grad601 single axis magnetic field gradiometer system. It should be read in conjunction with the product brochure (ds1800), which can be fo...

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    Bartington instruments page 8 of 61 om1800/26 3. General description the grad601 is a single axis, vertical component fluxgate gradiometer comprising a dl601 data logger, bc601 battery cassette battery cassette, and either one or two grad-01-1000l cylindrical gradiometer sensors (figure 1) mounted o...

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    Bartington instruments page 9 of 61 om1800/26 the grad601-2, with two sensors, records two lines of data during each traverse and reduces the survey time and distance walked to one half that of using a single sensor gradiometer. Both versions can operate in one of two modes: figure 2 grad601-2 dual ...

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    Bartington instruments page 10 of 61 om1800/26 mode function grid the instrument can be used: • as a survey tool, where data is logged while covering the site in parallel or zigzag paths. Data is saved in grids of 10x10, 20x20, 30x30 or 40x40m. The magnetic gradient is measured along a series of lin...

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    Bartington instruments page 11 of 61 om1800/26 4. Battery cassette and charger the gradiometer battery is a sealed lithium ion type and is housed in a sealed, separate cassette (figure 4a) which also contains the charging circuitry. 4.1. Charging the battery to charge the battery, connect the mains ...

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    Bartington instruments page 12 of 61 om1800/26 note: the battery contains electronic protection against short circuit which, if activated, will reset after a delay of 10 minutes. 4.2. Changing the battery the battery or anti-surge fuse can be replaced by the operator. Remove the back cover of the ba...

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    Bartington instruments page 13 of 61 om1800/26 4.3. Shipping the battery caution: batteries and equipment containing batteries should only be shipped in accordance with local regulations. Refer to the iata website ( www.Iata.Org ) for regulations regarding air transport. Caution: if there is any dou...

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    Bartington instruments page 14 of 61 om1800/26 note: assemble the gradiometer such that the arrows marked on the sensors are carefully aligned to point in the direction in which the operator will walk. This will assist the operator in pointing the arrows in the required direction during the set-up p...

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    Bartington instruments page 15 of 61 om1800/26 6. Connections the functions of the sockets on the underside of the data logger are indicated in the label on the front side of the instrument. Caution: only connect/disconnect the cable from data logger to sensors with the data logger powered off. Not ...

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    Bartington instruments page 16 of 61 om1800/26 7. Grad601-2 carrying harness the harness supplied with the dual sensor gradiometer is shown in figure 8. This completely relieves the operator’s arms of the weight of the gradiometer system, allowing easy operation of the controls. The harness comprise...

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    Bartington instruments page 17 of 61 om1800/26 9. Setting up the gradiometer must be set up using an automated procedure to help it adjust to the environment in which it is to be operated. The same procedure also removes alignment errors and scaling differences between the sensing elements forming t...

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    Bartington instruments page 18 of 61 om1800/26 key function on/off controls the power to the unit and sensors. Press to alternately apply and remove power. When the display is blank, the power is off. When the display is active, the power is on. A short delay is incorporated. Caution: if power is re...

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    Bartington instruments page 19 of 61 om1800/26 11.1. Main menu: grid mode the items in the grid mode main menu are as follows: • start survey • start scan • output data • delete data • set parameters • adjust gradiometer • system reset the two-line display will show only two items at a time. The fir...

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    Bartington instruments page 20 of 61 om1800/26 11.2. Set parameters menu: grid mode from the main menu select set parameters and press enter. This will give a further menu with default parameters set as shown in the table below. Use the arrow keys to select each item in turn, and then press the step...

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    Bartington instruments page 21 of 61 om1800/26 threshold : 1 nt select the deviation in nt at which the alarm is required to operate during a scan operation: increments in units, tens and hundreds and thousands of nt. When the field deviates by the level selected, the alarm message will be shown in ...

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    Bartington instruments page 22 of 61 om1800/26 the sampling frequency can be changed in the parameters menu, as in nmea mode this is not based upon grid size or walking speed. The ranges and resolution provided in nmea mode are the same as in grid mode: see gradiometer range and resolution . It is s...

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    Bartington instruments page 23 of 61 om1800/26 12.2. Capturing data in nmea mode whilst in nmea mode, the dl601 data logger can be connected to any external data logger that is capable of receiving nmea messages. An nmea gps device can then be plugged into the same logger and the data can be correla...

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    Bartington instruments page 24 of 61 om1800/26 note: each time the height settings are adjusted, the system must be set up again using the adjust gradiometer menu item before use. See checking and adjusting the sensors . 14. Operator magnetic hygiene note: the grad601 gradiometer is a very sensitive...

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    Bartington instruments page 25 of 61 om1800/26 automatically applies corrections, must be carried out in a previously selected low magnetic gradient area. Note: the setting-up procedure takes only a few minutes. It should be carried out after the instrument has been assembled and left switched on fo...

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    Bartington instruments page 26 of 61 om1800/26 easily identified features in the landscape on the north/south and east/west directions from the magnetically clean area selected above. Note: be sure to remove the compass from the area afterwards or it will interfere with the setup procedure. 2. Opera...

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    Bartington instruments page 27 of 61 om1800/26 the operator should keep the centre of the assembly over a fixed point. This is most easily achieved using the harness. Note: when the display requests that the sensors be moved to the opposite direction, rotate the gradiometer through 180 degrees for t...

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    Bartington instruments page 28 of 61 om1800/26 the controls are too far out of adjustment, the controls will be re-set automatically and the procedure will be re-started, with the full-scale range set to 1000nt and the fields displayed with a resolution of 1nt. After completing the procedure with th...

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    Bartington instruments page 29 of 61 om1800/26 the threshold function selects the field gradient at which the frequency of the audio output will increase. The audio tone increases from the alarm point to about ten times this value with increasing gradient levels. In scan mode, the screen is refreshe...

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    Bartington instruments page 30 of 61 om1800/26 the number of lines of data recorded will be determined by the size of the grid and the line spacing selected as lines/m. For the grad601-1 single sensor gradiometer, one line of data will be recorded for each traverse. For the grad601-2 dual sensor gra...

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    Bartington instruments page 31 of 61 om1800/26 will select 1 line/m but will traverse the grid at 2m intervals. Thus, for a 10x10m grid, only five traverses will be walked but ten lines of data will appear in the results at the appropriate positions after downloading. Results from each sensor are lo...

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    Bartington instruments page 32 of 61 om1800/26 grids may be surveyed using parallel traverses ( figure 10 ) or zigzag ( figure 11 ). The set parameters option allows the initial starting direction to be saved as part of the header information. Figure 12: possible starting points for first traverse. ...

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    Bartington instruments page 33 of 61 om1800/26 17.2.3. Lines and positions to interface the data of one grid with others to form a larger area map, the lines are spaced symmetrically in one direction and the values are measured at positions spaced symmetrically along the lines. The first line should...

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    Bartington instruments page 34 of 61 om1800/26 if we consider a 30mx30m grid with a line spacing of 1m, then the first line is positioned 0.5m from the top edge of the grid and the remaining lines are then spaced at 1m intervals down the grid. The last line is 29.5m from the top of the grid. Similar...

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    Bartington instruments page 35 of 61 om1800/26 with suitable ropes. It is also convenient to lay a rope along each traverse with 1m rope markers on it to allow the operator to keep pace with the data logging. 17.3. Surveying at 1 line/m a line spacing of 1m ( lines/m set to 1 in survey parameters) i...

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    Bartington instruments page 36 of 61 om1800/26 17.4.1. Surveying at 2 lines/m when using the grad601-2 dual sensor gradiometer for surveying at 2 lines/m with a parallel or zigzag traverse pattern, the operator must follow exactly the appropriate pattern shown in figures 17 and 18. Figure 17: dual s...

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    Bartington instruments page 37 of 61 om1800/26 traverse no. Positioning of sensor and beam centre 1 left-hand sensor at 0.25m and therefore centre of the beam at 0.75m from edge of the grid. 2 centre of beam 1.25m from edge of the grid. 3 centre of beam 2.75m from edge of the grid. 4 centre of beam ...

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    Bartington instruments page 38 of 61 om1800/26 traverse no. Positioning of sensor and beam centre 1 left-hand sensor at 0.125m and therefore centre of beam at 0.625m from the edge of the grid. 2 centre of beam 0.875m from edge of the grid. 3 centre of beam 1.125m from edge of the grid. 4 centre of b...

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    Bartington instruments page 39 of 61 om1800/26 note: for a grad601-2 dual sensor gradiometer, use a trapeze with 1m between the two ropes. Mark the ropes defining the start and end of each traverse such that placing the centre marks of the trapeze over the marks on the edge ropes guides the operator...

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    Bartington instruments page 40 of 61 om1800/26 during a traverse the data logger will display the current gradiometer readings and the grid, traverse and position numbers. The data logger prompts the operator to start each new traverse. When the last line is completed, the operator will be prompted ...

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    Bartington instruments page 41 of 61 om1800/26 back one trav pressing enter once will cause the displayed position number to return to 1, ready to start the traverse again. Further operations of the enter key will cause the traverse number to be decremented. If the option is selected before starting...

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    Bartington instruments page 42 of 61 om1800/26 note: after restarting, if the survey parameters are changed before continuing with the interrupted grid then the data may be saved in the wrong format and false results may be seen. Note: if a download is attempted with a grid still incomplete then the...

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    Bartington instruments page 43 of 61 om1800/26 19.1. Installing the grad601 datalog software the firmware version used by the unit is displayed at start-up. Firmware version used software version to use version 7.4 version 3.16 version 6.6 version 3.16 version 6.3 version 3.13 place the cdrom in the...

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    Bartington instruments page 44 of 61 om1800/26 when all data has been sent, a checksum is sent to validate the data. If the checksums do not match then an error has occurred and the operator will be prompted to repeat the download operation or proceed with the data as received. If the data is receiv...

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    Bartington instruments page 45 of 61 om1800/26 other data processing programs may require the z string or xyz file format, with a separate header file. When all parameters are correct, select save or save all. If the skip or save operations are used followed by the save all operation, the correct gr...

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    Bartington instruments page 46 of 61 om1800/26 19.4.2. Z string format in the single-file z string format the start of the same data will appear as shown (left). The data represents a continuous stream of gradiometer readings, re-formatted as though they had been collected using a single sensor work...

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    Bartington instruments page 47 of 61 om1800/26 2 position in the y direction in metres. The y direction represents the spacing between traverses. So that the plotted values correspond with the spreadsheet view, the first traverse represents the maximum value of y and the last traverse corresponds to...

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    Bartington instruments page 48 of 61 om1800/26 integer marker 32700 start of header 32701 end of header 32702 dummy data 32703 end of data 32704 end of file 32705 end of transmission (this will be followed by a two-byte checksum) 20.3. Transmission format each grid has a 10-integer header containing...

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    Bartington instruments page 49 of 61 om1800/26 20.3.2. Gradiometer data the header is followed by the data as recorded in zigzag or parallel form. If a dual sensor gradiometer is used then the first integer represents the left-hand sensor reading and the second integer represents the right-hand sens...

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    Bartington instruments page 50 of 61 om1800/26 ensure a magnetically quiet area is used: an area chosen to perform the adjustment should be examined using scan mode first. A good set-up area has less than 0.5nt variation in magnetic gradient over a 1.5m x 1.5m area. Ensure you face in one direction ...

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    Bartington instruments page 51 of 61 om1800/26 note: this will also cause the data memory to be cleared and the parameters set in the set parameters menu to be changed to the initial default values. Report the occurrence of any error messages to support@bartington.Com. 21.2.1. Power loss caution: if...

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    Bartington instruments page 52 of 61 om1800/26 power loss during ‘please wait…’ after ‘back one traverse’ is selected: power loss while carrying out this function can lead to different symptoms, which could include the loss of a sector. Grids from previous sectors will still be recoverable. Power lo...

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    Bartington instruments page 53 of 61 om1800/26 23. End of life disposal this product (electrical and electronic equipment) should not be placed in municipal waste. Check local regulations for disposal of electronic products. 23.1. Waste electrical and electronic equipment (weee) regulations the grad...

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    Bartington instruments page 54 of 61 om1800/26 appendix: practical aspects of surveying this section describes practical aspects of setting up and using the grad601 single and dual sensor gradiometers for archaeological prospecting, and for detailed mapping of archaeological features. Note: some poi...

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    Bartington instruments page 55 of 61 om1800/26 • it is helpful if the site is divided into rows of regular grids. Grids of 30x30m are normal, but difficult areas may be surveyed using 10x10m or 20x20m grids, and 40x40m grids can be used where larger areas are involved. • the grids will be recorded i...

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    Bartington instruments page 56 of 61 om1800/26 a.4. Grids, lines and positions • each grid is normally surveyed with a line interval of 1m, and a sample interval of 0.25m along the line of the traverse. This is a good compromise between the sampling rate and walking distance, and provides good resol...

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    Bartington instruments page 57 of 61 om1800/26 for a single sensor gradiometer, the first mark should be at 1m from the end and subsequent marks at 2m intervals. This corresponds to the arrangement in figure 12 . For a dual sensor gradiometer, the first mark should be at 2m, and subsequent marks at ...

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    Bartington instruments page 58 of 61 om1800/26 the second traverse line. A dual sensor gradiometer will be carried with one sensor at 0.5m and the other at 1.5m for the first traverse. When the first two traverses have been recorded, the trapeze is moved to the next mark on the edge lines and the ne...

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    Bartington instruments page 59 of 61 om1800/26 notes.

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    Bartington instruments page 60 of 61 om1800/26.

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    Om1800/26 the copyright of this document is the property of bartington instruments ltd. Bartington® is a registered trade mark of bartington instruments limited in the following countries: united kingdom, australia, brazil, canada, china, european union, india, japan, norway and the united states of...