Manual Hand-held Gaussmeter BGM101

Transcription

1 Manual Hand-held Gaussmeter BGM101

2 Inhaltsverzeichnis Introduction... 3 Measuring Príncipe... 3 Technical data:... 4 Scope of delivery... 3 Optional accessories... 4 Operating elements of the hand-held Gaussmeter BGM Keys... 6 Menu... 7 Axial and transverse measuring probe Operating instructions Handling measuring probes PC Software and Data Acquisition Maintenance and cleaning Support Page 2

3 Introduction The hand-held Gaussmeter BGM-101 for mobile AC and DC measurement of magnetic fields has been developed for a wide range of applications and is characterized by its extremee accuracy and easy handling. This device is operated via a touch screen display supported by three touch keys. Measuring Príncipe The Hall Effect describes the occurrence of electric voltage in a conductor through which current flows and which is located in a stationary magnetic field. The voltage flows down through the conductor vertically parallel to the current flow and to the direction of the magnetic field and is called Hall voltage UH. In this process a constant current is present adjacent to the Hall sensor. As soon as the Hall sensor is moved into a magnetic field, the electrons move in one direction depending on the polarity, whereby the so-called Hall voltage is created. This Hall voltage is emitted by means of further factors such as the speed of movement of the electrons and calibration factors of the sensors such as field strength around the Gaussmeter. Measurement of the magnetic field strength is in A7m or Oersted. Becausee of the linear relationship of magnetic field (H) and magnetic flux density (B) in air the display of magnetic flux density in Gauss or Tesla has become the accepted method in field measurement.(conversion of field and flux density in air: 1 Gauss = 10-4 Tesla = 10³ A/m =12,56 Oe) B = µ 0 * H Page 3

4 Technical data: Display: Measuring resolution: Multicolour Backlight Touch TFT (320x240 px) 0.1 Gauss (200 Gauss range) Sampling of measuring values: DC accuracy: AC accuracy: Frequency range: Measuring ranges: Measuring units: samples/sec. (Digital Noise Filter) ±0,5% of the maximum measuring range ±0,5% DC to 10 khz 4 measuring ranges, divided as follows: 4 x 10-3 T 40 x 10-3 T 400 x 10-3 T 2 T 40 G 400 G 4 x 10 3 G 20 x 10 3 G 40 Oe 400 Oe 4 x 10 3 Oe 20 x 10 3 Oe 3 x 10 3 A/m 30 x 10 3 A/m 300 x 10 3 A/m 1,5 x 10 6 A/m Gauss, Tesla, Oersted, A/m Temperature range: Measuring device temperature drift: Weight: Dimensions: Interface: Battery: Other: 0 to 85 C 0.05% / C 185g 125 x 75 x 25 mm USB 2.0 (loading and data transmission function) LiPO 3.7V 2500 mah Impulse measurement up to 50µs True RMS measurement Memory for 200 minimum and maximum values Relative measurement, alarm function, bar chart in display Personal settings memory Page 4

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6 Scope of delivery The Gaussmeter can be supplied with the following accessories: 1. Hard-top case 2. At least 1 measuring probe ( depending on the order) Transverse probe (for measuring magnetic fields vertical to the probe) Axial probe(for measuring magnetic fields parallel to the probe) Both 3. Probe extension cable (1 metre) 4. USB loading and data cable 5. User manual (CD ROM) 6. USB driver (Windows XP and Win7) for transmission of data to PC. (CD ROM) Page 3

7 Optional accessories 1. BZC 101 zero field chamber. Small measuring chamber for eliminating external magnetic fields for quick calibration of the measuring probe. The shielding of a static external magnetic field corresponds to approx. 60 db. The chamber has a diameter of 15 mm. External dimensions are 65mm x 25mm x 25mm. 2. BPC-101 probe extension cable (1 metre) 3. Aluminium case with padded lining Page 4

8 Operating elements of the hand-held Gaussmeter BGM-101 Page 5

9 Keys POWER/ STANDBY To switch the device on or off press for half a second. When this key is pressed quickly the device goes into standby and can be switched into operating mode again in the same way. RUN/MENUE NULL/Reset Up/Down Press the key for half a second to access the menu and also to return to run mode. For zero calibration of individual ranges press the key for half a second. (During zero calibration please remember to insert the probe in the BROCKHAUS zero chamber) When this key is pressed quickly the peak memory is cleared. With these two keys the measuring ranges can be switched to RUN mode. In the menu it is possible to switch between different options. Page 6

10 Menu 1. Acquisition 1.1. Relative Ref. Setting a reference value. The function of the relative measurement reference is activated in menu item Alarm Comparator LO Setting of a lower comparator threshold value which is set as the lower limit when measuring Comparator HI Setting of an upper comparator value which as set as the upper limit when measuring Symbols In alarm mode a visual notification appears in the display when the upper and lower measuring values exceed the comparator thresholds which have been set Beep Signal In alarm mode an acoustic signal is heard when the upper and lower measuring values exceed the comparator thresholds which have been set LO Filter Settle 1,6 s Settle 400 ms Settle 100 ms 1.4. HI Filter Detect 1,6 ms Detect 400 µs Detect 100 µs Page 7

11 2. Visualization The different measuring modes can be selected here. When one mode has been activated, measurements are carried out in this mode only. The following measuring modes are available: - DC - AC - DC + AC - DC rel. - AC rel. The units for output are also set here (see menu 2.6 output unit). In the Config-Menu of the individual modes the display setting can be adjusted during measurement DC Config Span Info Options of Fast Peak and Min / Max Fast Peak Displays the minimum and maximum peak as well as the difference between these peaks Min / Max Displays the minimum and maximum measured value as well as the difference between these values Bar graph Visual display of the individual ranges, both positive and negative; serves as an indicator for switching ranges. In auto range mode this happens automatically Alarm The alarm is activated in DC mode. The upper and lower limits can be set in menu 1.2. It is also possible, when the alarm is active, to set the currently measured value directly as the lower or upper limit in operating mode. Page 8

12 2.2. AC Config Min / Max Displays the minimum and maximum measured values as well as the difference between these two values Bar graph Visual display of the individual ranges, both positive and negative; serves as an indicator for switching over ranges. In auto range mode this happens automatically Alarm Here the alarm is activated in AC mode. The upper and lower limits can be set in menu 1.2. It is also possible, when the alarm is active, to set the currently measured value directly as the lower or upper limit in operating mode DC + AC Config DC Bar graph As well as display in an AC bar graph, it is also possible to display a DC bar graph of the individual ranges, in the positive and negative ranges; serves as an indicator for switching ranges. In auto range mode this happens automatically AC Bar graph As well as display in a DC bar graph, it is also possible to display an AC bar graph of the individual ranges, in the positive and negative ranges; serves as an indicator for switching ranges. In auto range mode this happens automatically Alarm Option of DC or AC alarm. Page 9

13 DC Alarm Here the alarm is activated in DC mode. The upper and lower limits can be set in menu 1.2. It is also possible, when the alarm is active, to set the currently measured value directly as the lower or upper limit in operating mode AC Alarm Here the alarm is activated in AC mode. The upper and lower limits can be set in menu 1.2. It is also possible, when the alarm is active, to set the currently measured value directly as the lower or upper limit in operating mode DC rel. Config Span Info Option of Min /Max and Relative Difference between nominal and actual in % Min / Max Display of minimum and maximum values / + [%] Display of relative difference between nominal and actual values in percent Bar graph Visual display of the individual ranges, both positive and negative; serves as an indicator for switching ranges. In auto range mode this happens automatically Alarm Here the alarm is activated in DC mode. The upper and lower limits can be set in menu 1.2. It is also possible, when the alarm is active, to set the currently measured value directly as lower or upper limit in operating mode.. Page 10

14 2.5. 5AC rel. Config Same functions as in 2.4 for DC, also available for AC mode Span Info Option of Min /Max and Relative Difference between nominal and actual in % Min / Max Display of minimum and maximum value / + [%] Display of relative difference between nominal and actual values in percent Bar graph Visual display of the individual ranges, both positive and negative; serves as an indicator for switching ranges. In auto range mode this happens automatically Alarm Here the alarm is activated in AC mode. The upper and lower limits can be set in menu 1.2. It is also possible when the alarm is active to set the currently measured value directly as the lower or upper limit in operating mode 2.6. Output Unit Output of values possible in the following units: Tesla [T] Gauss [G] Ampere per metre [A/m] Oersted [Oe] Page 11

15 3. Settings Here different settings can be made Display Setting the brightness of the display 3.2. Date / Time Setting date and time. Implemented with future firmware update Auto Power Off Setting for standby mode when the device is not actively used for a longer period USB Charge Setting whether the device should charge the battery if the device is connected to a PC via USB. ( Charging time is longer than when connected to a mains adapter.) 4. Memory This function is implemented with the future firmware update.. 5. Transfer The transfer functions are also implemented with the future firmware update Probe Setup 5.2. Setup Probe 5.3. No Probe Setup Page 12

16 Axial and transverse measuring probe The hand-held Gaussmeter can be operated with an axial or a transverse probe.. Illustration 1 Axial probe BAP101 ( height 800µm) Illustration 2 Transverse probe BTP101 (height 460µm) Page 13

17 Technical data of the Hall element: Kondition Max Value Tempo. Coefficient of VH B=50mT, C 125 C -0,06%/ C Temp. Coefficient of Rin B=0mT, C 125 C 0,3 %/ C Linearity B=0.1/0.5T, Ic=5mA 2% Page 14

18 Operating instructions 1. Switch on the hand-held Gaussmeter with the Power On switch. A display test is carried out for 1 second which briefly shows all the display options. For a further 3 seconds the programmed probe calibration number is shown. Now the device is ready for use. 2. Using the Gauss/Tesla button you can set the desired measuring unit. 3. Set the measuring range by using the Range button. As a rule you can also set AUTORANGE, but in some situations this may require up to 2 seconds for the measurements. If this is too long for a large number of measurements, making the settings manually is recommended. When the fields to be measured are very small, it is advisable not to use the AUTORANGE setting, since interference from external fields can influence the measuring range. (e.g. measurement of a small DC field could be influenced by interference from an AC field in the background). 4. Set the device to zero using the zero probe button in order to eliminate interference from small magnetic fields or offsets which have been preset. Hold the device away from a magnetic source and then set to zero. If you have an optional zero setting chamber, then insert the measuring probe into the chamber and set to zero. The measuring sensor should be kept as still as possible while being set to zero. If very strong interference from magnetic fields is o be eliminated, this can be done using the Relative button. First of all conduct a measurement of the source of interference and press the Relative button once to accept the measured value as a reference. 5. Max Hold und Max Hold Reset Function The Max-Hold-Function shows the largest magnetic field measured after a reset has been carried out. To activate this press the Max Hold button and start the measurement. The highest value so far is shown in the display. After completion of the measurement you can carry out a reset by activating the Max Reset key. When changing over the measuring range from AC to DC a reset of the Max Value takes place automatically. The Max Hold function can also be combined with the relative measurement. 6. The Relative function is for showing measurement deviations. For example small measurement deviations in very large fields can be measured. By activating the Relative button you can save a reference point during a measurement so that you can refer to this value for all subsequent measurements. Page 15

19 7. Alarm On/Off and Alarm Point. With these functions threshold values can be defined so that when these thresholds are exceeded an acoustic signal (alarm) is sounded. The alarm threshold has to be set manually. To do this press the button Alarm point and then enter a threshold value using the keypad. This must be confirmed with the Enter key. To activate the alarm press the Alarm on/off button (the text Alarm appears in the display.) Should the defined measuring value be exceeded during measurement the alarm tone will sound until the value falls again within the threshold. or you can also deactivate the alarm with the Alarm on/off button. 8. With the filter function you can activate a mean value measurement with 8 measuring values in order to stabilize the displayed measuring results. The filter function is activated or deactivated with the Filter key. 9. Locking the keypad. By pressing the Enter key for 10 seconds the keypad can be locked. LLL then appears in the display. In locked mode you can still switch the alarm and the whole device on and off. All preset functions are saved and the keys locked. Pressing the Enter key again for 10 seconds will unlock the keys again. Page 16

20 Handling measuring probes To avoid any damage to the sensitive measuring probes and to guarantee the best possible accuracy the following points must be observed: 1. Careful handling of measuring probes. The greatest care is to be taken when handling the measuring probes since the measuring sensors (Hall sensors) are on the surface of the measuring tip of the measuring probe. Heavy pressure or sudden impact on the measuring sensor may lead to breakage of the sensor. A broken Hall sensor cannot be repaired which means that the whole measuring probe must be replaced. Even if the sensor does not break, if too much pressure is applied to the sensor this may lead to falsification of the measuring results so that the measuring probe has to be recalibrated by the manufacturer. To avoid damage the flexible handle of the measuring probes should never be bent more than 45. No weight should ever be applied to the measuring probe and the probe should never be clamped. After use the measuring probe should be stored in the tubular packaging supplied. 2. General preparation and operation of the measuring probe The measuring probe should be allowed to warm up for approx. 5 minutes before starting measurements to ensure the highest degree of accuracy. When using an optional zero chamber, this should have the same ambient temperature as that to which the probe is exposed. The displayed DC polarity plays a role in DC measurements and is defined by the position of the Hall sensor. On transversal probes the black head shows the direction of the positive magnetic flux. Page 17

21 The direction of positive magnetic flux is on the tip of the axial probe. (see illustration). If the exact direction of the magnetic field is not known, this can be defined by slowly rotating the measuring probe. The field strength rises and falls during this slow rotation backwards and forwards. Page 18

22 PC Software and Data Acquisition BGM Quickstart Guide for.net applications The BGM.dll enables access to the hand-held Gaussmeter via your.net application. This document describes the steps required to make the recorded measured values available for this application. DeviceManager.vb of the demo application supplied serves as a model. 1. Integrate the BGM.dll into your.net project. 2. Create or make a reference to the BGM object of thebgm.dll Public _bgmdevice As BGM.DeviceInterface = BGM.DeviceInterface.Instance 3. Register or implement the event handlers listed below to communicate the connection status, the serial number and the measuring results. Registration of event handlers AddHandler _bgmdevice.results, AddressOf _bgmdevice_results AddHandler _bgmdevice.serialnumber, AddressOf _bgmdevice_serialnumber AddHandler _bgmdevice.connectionfound, AddressOf _bgmdevice_connectionfound AddHandler _bgmdevice.connectionlost, AddressOf _bgmdevice_connectionlost Implementation of event handlers Private Sub _bgmdevice_results(byval dc As Double, ByVal ac As Double, _ End Sub ByVal dc_min As Double, ByVal dc_max As Double, _ ByVal ac_min As Double, ByVal ac_max As Double, _ ByVal lowpeak As Double, ByVal highpeak As Double, _ ByVal range As BGM.DeviceInterface.ResultsRangeT) Private Sub _bgmdevice_serialnumber(byval serialnumber As String) Page 19

23 End Sub Private Sub _bgmdevice_connectionfound() End Sub Private Sub _bgmdevice_connectionlost() End Sub 4. Set up a connection to the device _bgmdevice.connect("com1", , 8, IO.Ports.StopBits.One, IO.Ports.Parity.None, IO.Ports.Handshake.None) Now, periodically, the measured values of the hand-held Gaussmeter will be communicated to your.net application. To end communication to the hand-held Gaussmeter carry out the steps 5 and End the connection to the device. _bgmdevice.disconnect() 6. Delete the event handlers RemoveHandler _bgmdevice.results, AddressOf _bgmdevice_results RemoveHandler _bgmdevice.serialnumber, AddressOf _bgmdevice_serialnumber RemoveHandler _bgmdevice.connectionfound, AddressOf _bgmdevice_connectionfound RemoveHandler _bgmdevice.connectionlost, AddressOf _bgmdevice_connectionlost Page 20

24 Maintenance and cleaning In principle the Gaussmeter and the probes require no maintenance. Use a clean dry cloth to clean the device. The use of any additional cleaning substances containing solvents will damage the display and the housing of the Gaussmeter. Support In case of any problems with the Gaussmeter BGM101 please make a note of the software revision number and the serial number of the device and contact us: Dr. Brockhaus Messtechnik GmbH & Co. KG Gustav-Adolf-Str. 4 D Lüdenscheid Germany Tel.: Support.gaussmeter@BROCKHAUS.COM Page 21