AM BORSIGTURM 54
13507 BERLIN
Projekt Elektronik
TEL. 030 / 43 03 22 40
MESS - UND REGELUNGSTECHNIK GMBH FAX 030 / 43 03 22 43
Operating Manual
Made in Germany
Copyright Projekt Elektronik GmbH 26.02.2018
1. Warning
Observe personal protection rules!
Please read this Operating Manual carefully!
When measuring magnetic fields, consider and observe the
regulations concerning potential dangers caused by DC and AC
magnetic fields.
The direct influence of magnetic fields (for limits see DIN VDE 0848)
may be harmful to one's health.
The operation of cardiac pacemakers may be affected dangerous!
Examples for sources of potentially hazardous magnetic fields:
• ultrasonic sources
• induction heaters and furnaces
• magnetic resonance tomographs
• medical magnetic fields
More information can be obtained in the following documentation:
• Electromagnetic Compatibility (Elektromagnetische Verträglichkeit),
VDE, Vol. 1 to 4
• DIN VDE 0848
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2. Technical Advice
Please read this Operating Manual carefully!
2.1 Transverse Probe
The transverse probe has a blue protective cap which have to be unscrewed
before measurement.
Utmost care and attention are needed if magnets have to be measured that
are not mechanically fixed. Clashing poles can destroy the Hall element!
As the Hall element (ceramic) is very sensitive to pressure or shock,
mechanical stress must be avoided (risk of breakage)!
2.2 Transverse Probe Brass
When measuring fields of B > 20 mT and f > 10 kHz, the probe brass
should not be operated for more than 1 min in order to prevent excessive
heating of the brass tube with the Hall element inside!
Attention should be paid to the fact that at the probe a connection exist
between GND, cable shield, plug housing and brass tube. Possibly an
isolated installation of the probe and/or plug would be necessary to prevent
an unintended connection between measuring ground and protective earth.
2.3 Transverse Probe Hot
The transverse probe has a protective cap which have to be drawn off
before measurement.
Only the probe, the handle and the cable are temperature-resistant. The
probe connector with the electronic may only be operated up to +50 °C.
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2. Technical Advice
2.4 Transverse Probe Flex
The transverse probe has a protective cap which have to be drawn off
before measurement.
Only the probe itself is temperature-resistant. The handle, the cable and the
probe connector with the electronic may only be operated up to +50 °C.
No pressure shall be applied to the hall element (ceramic) because it is very
pressure sensitive (risk of breaking)!
2.5 Transverse Probe Wire
The wire probes are very sensitive. The wires of the probe may not be bend
at the element and may not be pulled.
Only the probe itself is temperature-resistant. The handle, the cable and the
probe connector with the electronic may only be operated up to +50 °C.
No pressure shall be applied to the hall element (ceramic) because it is very
pressure sensitive (risk of breaking)!
2.6 Axial Probe UAP
To be able to gain best stability in the 2 µT range the probe should be
switched on for at least 30 minutes.
The axis of the compensation potentiometer should not be exposed to
bending forces to prevent the axis and the potentiometer from damage.
2.7 AS-Probe Adapter
Attention should be paid that there is a connection between GND and cable
shield as well as the connector housing in the adapter cable. At brass
probes this is also connected to GND. Possibly an isolated installation of the
probe is necessary to prevent an unintended connection between measuring
GND and protective earth.
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2. Technical Advice
2.8 AS-Adapter 3
One should be aware, that the probes and all outputs have a common
ground. Especially when using the brass version of AS-probes (AS-NTM,
AS-LTM) an isolation between probe and other parts of the measurement
setup can be necessary. It should be noted that the three adapter cables (X,
Y, Z) and the probes provide a connection between the GND and the cable
shield as well as the connector housing. Possibly an isolated installation of
the probe is necessary to prevent an unintended connection between
measuring GND and protective earth.
2.9 ESD
Electrostatic discharges (> 0.5 kV) to the sensor can damage it. Structural
safety measures would affect measurement accuracy due to loss of
sensitivity.
2.10 Minimum Operation Conditions (EMC)
Measurement results may vary up to 2 % in the presence of strong HF fields
(> 3 V/m).
2.11 Ground Connection / Earthing
It should be observed, that in the probe a connection between GND, plug
shield, plug case and cable shield is made. At bass probes, this is also
connected to GND. Possibly an isolated installation of the probe is
necessary to prevent an unintended connection between measuring GND
and protective earth.
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3. Table of Contents
1. Warning .............................................................................................................. 2
2. Technical Advice ............................................................................................... 3
2.1 Transverse Probe ....................................................................................... 3
2.2 Transverse Probe Brass ............................................................................. 3
2.3 Transverse Probe Hot ................................................................................. 3
2.4 Transverse Probe Flex ............................................................................... 4
2.5 Transverse Probe Wire ............................................................................... 4
2.6 Axial Probe UAP ......................................................................................... 4
2.7 AS-Probe Adapter ....................................................................................... 4
2.8 AS-Adapter 3 .............................................................................................. 5
2.9 ESD ............................................................................................................ 5
2.10 Minimum Operation Conditions (EMC) ....................................................... 5
2.11 Ground Connection / Earthing .................................................................... 5
3. Table of Contents .............................................................................................. 6
4. List of Figures ................................................................................................. 11
5. Description ...................................................................................................... 13
5.1 Purpose of a Magnetic Field Meter ........................................................... 13
5.2 General Description of Operation ............................................................. 13
5.2.1 Teslameter FM 302 ....................................................................... 13
5.2.2 AS-Active-Probe ............................................................................ 15
5.2.2.1 Probe Extension Cord ..................................................... 17
5.2.3 AS-Probe Adapter ......................................................................... 17
5.2.4 AS-Adapter 3 ................................................................................. 18
5.3 Items Supplied .......................................................................................... 19
6. Operation ......................................................................................................... 20
6.1 Introduction ............................................................................................... 20
6.2 Safety Notes ............................................................................................. 20
6.3 Teslameter FM 302 ................................................................................... 21
6.3.1 Controls and Connectors ............................................................... 21
6.3.1.1 Housing ........................................................................... 22
6.3.1.2 Handle ............................................................................. 22
6.3.1.3 top hat rail adapter (optional) ........................................... 22
6.3.1.4 Power Switch ................................................................... 22
6.3.1.5 Keypad ............................................................................ 22
6.3.1.6 Display ............................................................................. 23
6.3.1.7 Key “zero” – Offset Compensation .................................. 25
6.3.1.8 Key “DC AC” – Measuring Mode ..................................... 27
6.3.1.9 Key “gain” – Measuring Range ........................................ 27
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3. Table of Contents
6.3.1.10 Key “unit” – Unit .............................................................. 28
6.3.1.11 Key “rel abs” – Relative Measurement ............................ 28
6.3.1.12 Key “min max” – Minimal Measurement, Maximal
6.3.1.13 Key “time” – Measuring Time .......................................... 29
6.3.1.14 Key “filter” – Filter ........................................................... 30
6.3.1.15 Acoustic Feedback ......................................................... 31
6.3.1.16 Analog Output ................................................................. 31
6.3.1.17 Probe Connector ............................................................. 32
6.3.1.18 USB Interface ................................................................. 32
6.3.1.19 Power Connector ............................................................ 32
6.3.1.20 Battery Compartment ...................................................... 32
6.3.2 Usage of The Teslameter FM 302 ................................................ 33
6.3.2.1 Time Response of Display and Analog Output ............... 34
6.3.2.2 Power Supply .................................................................. 35
6.3.2.3 Battery / Accumulator Operation ..................................... 35
6.3.2.4 Power Adapter Operation ............................................... 35
6.3.2.5 USB Operation ................................................................ 36
6.3.2.6 Display of Units with older AS-Active-Probe ................... 37
6.3.3 USB Interface ............................................................................... 38
6.3.3.1 General ........................................................................... 38
6.3.3.2 Driver Installation Windows............................................. 38
6.3.3.3 Driver Installation Linux .................................................. 38
6.3.3.4 Configuration of the Virtual Serial Port ............................ 39
6.3.3.5 General about Commands .............................................. 39
6.3.3.6 Command “absolute” ...................................................... 40
6.3.3.7 Command “coupling” ...................................................... 40
6.3.3.8 Command “default” ......................................................... 40
6.3.3.9 Command “digits” ........................................................... 41
6.3.3.10 Command “filter” ............................................................. 41
6.3.3.11 Command “fmstatus” or “status” ..................................... 41
6.3.3.12 Command “gain” ............................................................. 42
6.3.3.13 Command “inttime” or “time” ........................................... 43
6.3.3.14 Command “keys” ............................................................ 43
6.3.3.15 Command “logging” ........................................................ 44
6.3.3.16 Command “maximum” .................................................... 44
6.3.3.17 Command “minimum” ..................................................... 45
6.3.3.18 Command “range” ........................................................... 45
6.3.3.19 Command “relative” ........................................................ 45
6.3.3.20 Command “serial” ........................................................... 46
6.3.3.21 Command “sound” .......................................................... 47
6.3.3.22 Command “unit” .............................................................. 47
6.3.3.23 Command “version” ........................................................ 48
6.3.3.24 Command “zero” ............................................................. 48
Measurement .................................................................. 29
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3. Table of Contents
6.3.4 Control Software FM 302 Control .................................................. 49
6.3.4.1 General Description ......................................................... 49
6.3.4.2 Installation ....................................................................... 50
6.3.4.3 Connection to Teslameter FM 302 .................................. 50
6.3.4.4 Display and Setting of parameters .................................. 51
6.3.4.5 Oscilloscope Display ....................................................... 52
6.3.4.6 Logging of Measured Values ........................................... 53
6.3.4.7 Limit Comparator ............................................................. 56
6.3.4.8 Restore Factory Settings ................................................. 58
6.3.4.9 Uninstall ........................................................................... 58
6.3.4.10 Source Code ................................................................... 58
6.4 AS-Active-Probe ....................................................................................... 59
6.4.1 Polarity .......................................................................................... 59
6.4.1.1 Transverse Probe ............................................................ 59
6.4.1.2 Axial Probe ...................................................................... 60
6.4.2 Measuring Arrangement ................................................................ 61
6.4.3 Precision and Repeatability ........................................................... 62
6.4.4 Winding up of Cables .................................................................... 62
6.4.5 Transverse Probe AS-NTP 0,6 ...................................................... 63
6.4.6 Transverse Probe Brass AS-NTM, AS-NTM-2, AS-LTM ............... 63
6.4.7 Transverse Probe Hot AS-NTP-Hot-05 ......................................... 63
6.4.8 Transverse Probe Flex AS-NTP-Flex, AS-NTP-Flex 0,6 ............... 64
6.4.9 Transverse Probe Wire AS-NCu-Wire ........................................... 64
6.4.10 Axial Probe AS-HAP, AS-NAP, AS-LAP ........................................ 65
6.4.11 Axial Probe AS-UAP GEO-X, AS-UAP Lot .................................... 65
6.4.12 Usage of the AS-Active-Probes ..................................................... 67
6.4.12.1 Usage with the Teslameter FM 302 ................................. 67
6.4.12.2 Usage as Autonomous Transducer ................................. 67
6.4.12.3 Usage with the AS-Probe Adapter ................................... 69
6.4.12.4 Usage with the AS-Adapter 3 .......................................... 69
6.4.13 Zero Chamber (optional) ............................................................... 69
6.4.14 Linearity Curves (optional) ............................................................. 69
6.5 AS-Probe Adapter ..................................................................................... 71
6.5.1 Controls and Connectors ............................................................... 71
6.5.2 Structure ........................................................................................ 72
6.5.2.1 Supply Voltage Inputs...................................................... 73
6.5.2.2 Power LED ...................................................................... 73
6.5.2.3 Probe Supply ................................................................... 73
6.5.2.4 Probe Signal Input ........................................................... 73
6.5.2.5 Measurement Signal Output ............................................ 73
6.5.2.6 Gain Switch ..................................................................... 74
6.5.3 Adapter Cable ............................................................................... 74
6.5.4 Usage of the AS-probe adapter ..................................................... 75
6.6 AS-Adapter 3 ............................................................................................ 76
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3. Table of Contents
6.6.1 Controls and Connectors .............................................................. 76
6.6.2 Overview of Controls and Connections ......................................... 76
6.6.2.1 Supply Voltage Inputs ..................................................... 78
6.6.2.2 Power LED ...................................................................... 78
6.6.2.3 Probe Supply .................................................................. 78
6.6.2.4 Probe Signal Input .......................................................... 78
6.6.2.5 Measurement Signal Output ........................................... 78
6.6.2.6 Gain Switch ..................................................................... 79
6.6.3 Adapter Cable ............................................................................... 79
6.6.4 Usage of the AS-Adapter 3 ........................................................... 82
7. Technical Specifications ................................................................................ 85
7.1 Teslameter FM 302 (without AS-Active-Probe): ....................................... 85
7.2 AS-Active-Probes ..................................................................................... 88
7.2.1 Sensitivity Classes – Overview ..................................................... 90
7.2.2 AS-active-probes – Overview Normal ........................................... 93
7.2.3 AS-active-probes – Overview Earth Magnetic Field ...................... 94
7.2.4 AS-active-probes – Overview High Field ...................................... 94
7.2.5 AS-active-probes – Overview Low Field ....................................... 95
7.2.6 AS-active-probes – Overview Further Data .................................. 96
7.2.7 Axial Probe 12 T (AS-HAP) ........................................................... 97
7.2.8 Transverse Probe 2000 mT (AS-NTP 0,6) .................................... 98
7.2.9 Transverse Probe Brass 2000 mT (AS-NTM) ............................... 99
7.2.10 Transverse Probe Brass with Very High Precision 2000 mT (AS-
NTM-2) ........................................................................................ 100
7.2.11 Axial Probe 2000 mT (AS-NAP) .................................................. 101
7.2.12 Transverse Probe Hot with Improved Temperature Characteristics
2000 mT (AS-NTP-Hot-05) ......................................................... 102
7.2.13 Transverse Probe Flex 2000 mT (AS-NTP-Flex) ........................ 103
7.2.14 Transverse Probe Flex 2000 mT (AS-NTP-Flex 0,6) ) ............... 104
7.2.15 Transverse Probe Wire 2000 mT (AS-NCu-Wire) ....................... 105
7.2.16 Transverse Probe Brass 200 mT (AS-LTM) ................................ 106
7.2.17 Axial Probe 200 mT (AS-LAP) .................................................... 107
7.2.18 GEO-X Axial Probe 200 µT (AS-UAP GEO-X)............................ 108
7.2.19 Lot Axial Probe 200 µT (AS-UAP Lot) ......................................... 109
7.3 AS-Probe Adapter .................................................................................. 110
7.4 AS-Adapter 3.......................................................................................... 111
8. Maintenance .................................................................................................. 114
8.1 Visual Inspection .................................................................................... 114
8.2 Checking Battery .................................................................................... 114
8.3 Maintaining Accumulators ...................................................................... 114
8.4 Cleaning ................................................................................................. 115
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3. Table of Contents
8.5 Warranty Provisions ................................................................................ 115
9. Customer Service .......................................................................................... 116
9.1 Calibration............................................................................................... 116
9.2 Repairs ................................................................................................... 116
9.3 Follow-up Orders .................................................................................... 116
9.4 Disposal .................................................................................................. 116
10. EU Declaration of Conformity ...................................................................... 117
11. Index ............................................................................................................... 118
Gebrauchseinweisung FM 302 0203-116.docx
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4. List of Figures
Figure 1 Example of an order of FM 302 with three probes and options ................ 19
Figure 2 Controls and connectors FM 302 .............................................................. 21
Figure 3 Keypad of Teslameter FM 302 ................................................................. 22
Figure 4 Display of Teslameter FM 302 .................................................................. 23
Figure 5 Display of serial number and firmware version ......................................... 23
Figure 6 Display of Teslameter FM 302 .................................................................. 23
Figure 7 Display without probe ............................................................................... 24
Figure 8 Display while range overflow .................................................................... 24
Figure 9 Display battery state ................................................................................. 24
Figure 10 Display supply by power adapter or USB ............................................... 25
Figure 11 Display while offset compensation process ............................................ 25
Figure 12 Display error message offset out of range .............................................. 26
Figure 13 Display reset offset compensation .......................................................... 26
Figure 14 Display measuring mode ........................................................................ 27
Figure 15 Display in relative measurement ............................................................. 28
Figure 16 Display in minimal measurement ............................................................ 29
Figure 17 Display in maximal measurement ........................................................... 29
Figure 18 Display measuring timeout ..................................................................... 30
Figure 19 Display filter length ................................................................................. 30
Figure 20 Usage of Teslameter FM 302 ................................................................. 33
Figure 21 Time response ........................................................................................ 34
Figure 22 Display with not representable unit ......................................................... 37
Figure 23 Control software FM 302 Control ............................................................ 49
Figure 24 Value display of the control software ...................................................... 51
Figure 25 Control of keypad lock and acoustic feedback ........................................ 51
Figure 26 Control of the FM 302 settings ................................................................ 52
Figure 27 Oscilloscope-like display ......................................................................... 53
Figure 28 Setting logging parameter ....................................................................... 53
Figure 29 Log file example...................................................................................... 54
Figure 30 Single value logging ................................................................................ 54
Figure 31 Continuous value logging ....................................................................... 55
Figure 32 Log preview ............................................................................................ 56
Figure 33 Limit comparator ..................................................................................... 56
Figure 34 Oscilloscope display with limits of limit comparator ................................ 57
Figure 35 Reset to the factory settings ................................................................... 58
Figure 36 Measurements using a transverse probe ................................................ 59
Figure 37 Trigonometric of the measuring arrangement ......................................... 59
Figure 38 Measurements using an axial probe ....................................................... 60
Figure 39 Trigonometric function of the axial probe ................................................ 60
Figure 40 Measuring arrangement bar magnet ....................................................... 61
Figure 41 Measuring arrangement cylindrical coil ................................................... 62
Figure 42 Transverse probe 0,6 .............................................................................. 63
Figure 43 Transverse probe brass .......................................................................... 63
Figure 44 Transverse probe Hot ............................................................................. 63
Figure 45 Transverse probe Flex ............................................................................ 64
Figure 46 Transverse probe Flex 0,6 ...................................................................... 64
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4. List of Figures
Figure 47 Transverse probe Wire ........................................................................... 64
Figure 48 Axial probe ............................................................................................. 65
Figure 49 Axial probe AS-UAP GEO-X................................................................... 65
Figure 50 Axial probe AS-UAP Lot ......................................................................... 65
Figure 51 Controls connector AS-UAP ................................................................... 66
Figure 52 Usage of AS-active-probe with FM 302 .................................................. 67
Figure 53 Usage AS-probe at ±3 V......................................................................... 68
Figure 54 Pin configuration AS-probe at ±3 V ........................................................ 68
Figure 55 Structure AS-active-probe ...................................................................... 69
Figure 56 Zero Chamber ........................................................................................ 69
Figure 57 Typical linearity curves ........................................................................... 70
Figure 58 Controls and connections AS-probe adapter .......................................... 71
Figure 59 Structure AS-probe adapter.................................................................... 72
Figure 60 Adapter cable ......................................................................................... 74
Figure 61 Connection AS-probe adapter ................................................................ 75
Figure 62 Controls and connectors AS-Adapter 3 .................................................. 76
Figure 63 Structure AS-Adapter 3 .......................................................................... 78
Figure 64 Adapter cable „X, Y, Z” ........................................................................... 81
Figure 65 Connection AS-Adapter 3 with 1-axis AS-active probes ......................... 83
Figure 66 Connection AS-Adapter 3 with 3-axis AS-active probe .......................... 84
Figure 67 AS-NTP 0,6 transverse probe ................................................................ 88
Figure 68 AS-NTM, AS-LTM and AS-NTM-2 transverse probe brass .................... 88
Figure 70 AS-NTP-Hot-05 transverse probe .......................................................... 88
Figure 71 AS-NTP-Flex transverse probe .............................................................. 88
Figure 72 AS-NTP-Flex 0,6 transverse probe ........................................................ 88
Figure 73 AS-NCu-Wire transverse probe Wire ..................................................... 88
Figure 69 AS-NAP, AS-LAP and AS-HAP axial probe............................................ 89
Figure 74 AS-UAP GEO-X axial probe ................................................................... 89
Figure 75 AS-UAP Lot axial probe ......................................................................... 89
Figure 76 Size axial probe 12 T (AS-HAP) ............................................................. 97
Figure 77 Size transverse probe 2000 mT (AS-NTP 0,6) ....................................... 98
Figure 78 Size transverse probe brass 2000 mT (AS-NTM) ................................... 99
Figure 79 Size transverse probe brass 2000 mT (AS-NTM-2) ............................. 100
Figure 80 Size axial probe 2000 mT (AS-NAP) .................................................... 101
Figure 81 Size transverse probe Hot 2000 mT (AS-NTP-Hot-05) ........................ 102
Figure 82 Size transverse probe Flex 2000 mT (AS-NTP-Flex) ........................... 103
Figure 83 Size transverse probe Flex 2000 mT (AS-NTP-Flex 0,6) ..................... 104
Figure 84 Size transverse probe Wire 2000 mT (AS-NCu-Wire) .......................... 105
Figure 85 Size transverse probe brass 200 mT (AS-LTM) ................................... 106
Figure 86 Size axial probe 200 mT (AS-LAP) ....................................................... 107
Figure 87 Size GEO-X axial probe 200 µT (AS-UAP GEO-X) .............................. 108
Figure 88 Size Lot axial probe 200 µT (AS-UAP Lot) ........................................... 109
Figure 89 AS-probe adapter ................................................................................. 110
Figure 90 AS-Adapter 3 ........................................................................................ 112
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5. Description
5.1 Purpose of a Magnetic Field Meter
The Teslameter FM 302, the AS-active-probes, the AS-probe adapter and
the AS-Adapter 3 form a handy measuring system which allows to measure
magnetic fields in a wide scope of application. This includes alternating
fields of electromagnets as well as constant magnetic fields of permanent
magnets.
For normal use of the instrument, please refer to section 6 Operation.
5.2 General Description of Operation
The measuring system consists of the Teslameter FM 302 and/or AS-probe
adapter and/or AS-Adapter 3 at least one pluggable AS-active-probe which
contains the sensor.
By the use of pluggable probes, the system may be fast and easily adopted
to different measuring tasks. Depending on the probe, fields from a few
nano-Tesla up to 12 Tesla can be measured. After plugging in the desired
probe one can start to measure immediately without adjustment of zero and
scale since the AS-active-probes have an active electronic which matches
the properties of the sensor to the measuring range of the probe.
There are different probes available which fulfill the requirements
- to the geometry of the cavity to be measured,
- to the strength of the magnetic flux,
- to the treatment,
- to the size of the active sensor area,
- or to the operating temperature.
The selection of probes is regularly extended. This is done especially by
requests of customers.
5.2.1 Teslameter FM 302
The Teslameter FM 302 has a 4 ½ digit display and three measuring
ranges. The sensitivity of the ranges depends on the used probe and differ
in factor 10 and factor 100. The polarity is displayed by the sign. The
displayed unit can be switched between Tesla, Gauss, Oersted and A/m.
The Teslameter FM 302 can used to measure steady as well as alternating
magnetic fields up to 100 kHz (depending on the probe type). For AC-fields
alternatively the mean value (DC) or the effective value (true RMS) can be
displayed (see section 6.3.2 Usage of The Teslameter FM 302).
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5. Description
Another feature of the Teslameter FM 302 is the calibrated analog output,
which is useful for display purposes (oscilloscope, plotter), data logging
(computer) and field control. Here the measured signal in DC or AC coupling
can be selected.
The operation of the Teslameter FM 302 is done via the keypad with 8 keys
which allow to set the functions of the device. For example the measuring
time can be adjusted to meet the requirements of the respective measuring
task, depending if a rather fast capturing of measured values or low noise
measured values are more important. For further filtering a digital filter can
be activated which works as a moving average filter on the measured
values.
In addition to absolute measurement the Teslameter FM 302 offers a
function to relative measurement and for measuring the minimal and
maximal value.
Moreover the Teslameter FM 302 features a USB interface which allows to
control the device and read out the measured values. There are even more
control options available. Also the device can be powered via the USB
connection. At the computer side the Teslameter FM 302 appears as a
virtual serial port so it is easy to integrate the device into existing systems.
The Teslameter FM 302 with its AS-active-probes is not disturbed in its
function by stronger magnetic fields. The device works reliable even at a DC
field of 350 mT. Neither the actual measurement nor the communication with
the computer is interfered. It has just to be considered the occurring action
of force of the device. The main reasons are the battery and the probe
connector.
The Teslameter FM 302 is delivered with a control software. The software
allows to control all settings of the Teslameter via the PC. Thereby the
software offers the complete range of functions which are possible with the
commands via the USB interface.
Besides the simple display of the measured value the software offers an
oscilloscope like display of the last 100 measured values. The time axis
depends on the selected measuring time. The scale of the amplitude axis is
given by the connected probe and the selected sensitivity of the FM 302.
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5. Description
Additionally an amplification to one-tenth of the measurement range can be
activated. The created chart can be saved in different graphic formats.
The control software do not just allow to display the measured values of the
FM 302 but also allows to save them into a log file. For this two different
modes are offered. In the mode “single value logging” single measured
values can be saved with a key press (mouse or keyboard). This mode is
suitable for manual controlled measurements where a number of single
values has to be measured. Otherwise in the mode “continuous value
logging” the measured value are automatically stored continuously into the
log. This mode is suitable to record traces over longer periods of time.
For storing there can be chosen from two different formats. The log can be
saved in classic csv format (comma separated values) where the single data
blocks are separated by a comma and the period is used as decimal
separator. Alternatively the semicolon may be used for separating the data
blocks which makes available the comma as decimal separator. This
settings simplifies the import into software with German localization.
As another function the software offers a limit comparator. An upper and a
lower limit may be entered. The software shows if the current measured
value is below the lower limit, between both limits or above the upper limit.
This function allows e.g. the quick incoming inspection of permanent
magnets.
The polarity can be ignored while checking the compliance with the given
limits. Additionally the set limits can be displayed in the oscilloscope-like
display.
5.2.2 AS-Active-Probe
The AS-active-probes are active probes to measure the magnetic induction.
In contrast to most other available probes, the AS-probes contain an active
electronic so that a calibrated analog signal is available at the plug.
The transverse probe made of glass fiber fabric (AS-NTP 0,6) with their
slight thickness make it possible to measure in narrow air gaps and difficultto-reach locations. For transportation the probe is protected by a cap.
Further-more the probe carrier is temperature resistant up to 100 °C.
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5. Description
For rough operating conditions the transverse probe is provided in a design
with brass protective tube (AS-LTM, AS-NTM). However they are thicker
than the AS-NTP 0,6.
The transverse probes AS-NTP-Flex and AS-NTP-Flex 0,6 are made with a
strip of very thin, extreme flexible and bendable material. They are qualified
to measure remarkable hard to reach locations and smallest air gaps.
Furthermore the probe carrier is temperature resistant up to 100 °C at the
AS-NTP-Flex and even up to 150 °C at the AS-NTP-Flex 0,6.
The probe AS-NCu-Wire is an extra thin sensor connected with very light
wires. Thus the probe is suited to measure at closed quarters and to mount
into complex measurement setups.
At very high demands to accuracy and temperature stability the probe
AS-NTM-2 may be used. Linearity error and temperature drift have been
highly reduced compared to the other probes.
The transverse high-temperature probe AS-NTP-Hot-05 is designed to
measure even at high temperatures up to 150 °C and at low temperatures
down to –40 °C. The probe itself and the probe cable are constructed to
permanently endure those temperatures.
The also available axial probes (AS-LAP, AS-NAP, AS-HAP) have a small
diameter and thus are suitable to measure fields in small coils.
With the axial AS-UAP probes particularly small fields can be measured with
a resolution down to one nano Tesla. Furthermore it has the facility to
compensate ±70 µT which for example provides the possibility to
compensate the earth magnetic field. So only differences are measured
which can be done with higher resolution.
The AS-UAP probe is available in two types. The AS-UAP GEO-X probe is
suitable for general measuring tasks while the AS-UAP Lot probe with their
special plummet housing with weighted tip is mainly suitable for measuring
the vertical component of the earth magnetic field.
All AS-active-probes can be used without the Teslameter as transducer at
an PLC, see section 6.4.12.2 Usage as Autonomous Transducer.
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5. Description
5.2.2.1 Probe Extension Cord
Based on the fact, that the AS-active-probes are active probes, whose
electronic outputs a calibrated voltage signal related to the measured flux
density, a probe extension cord can be inserted between AS-active-probe
and Teslameter FM 302, AS-Adapter 3 or PLC without negative influence on
the measuring signal. So even wider distances between measured object
and measuring device can be bridged.
Appropriated extension cords are optional available in different lengths.
5.2.3 AS-Probe Adapter
The AS-probe adapter is designed to autonomously operate our ASactive-probes without Teslameter.
As a result of the wide supply voltage range of 9 VDC to 36 VDC the AS-probe
adapter may be used universal in different system configurations.
Furthermore the AS-probe adapter galvanically isolates the power supply
from the probe supply and the measuring electronic.
The AS-probe adapter provides high stable ±3 V necessary to supply the
AS-active-probes. To ease the connection of the AS-active-probe to existing
analog inputs with ±10 V input range, the AS-probe adapter contains an
integrated amplifier. This amplifies the output signal of the AS-active-probes
from ±2 V to ±10 V. With a switch, an additionally 10times higher gain can
be chosen which allows to perform even sensitive measurements.
The analog output of the adapter is calibrated and thus can be used e.g. for
displaying magnetic pulses in the µs-range (oscilloscope), recording of
measurements and for field control. The bandwidth of the analog output
reaches from DC to a least 100 kHz. Therefore it is suitable for measuring
both constant magnetic fields and alternating magnetic fields.
Included in delivery is an adapter cable which allows the easy connection of
the 15-pole SubD connector of the AS-active-probes with the screw
terminals of the AS-probe adapter.
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5. Description
5.2.4 AS-Adapter 3
The AS-Adapter 3 is used for the autonomous operation of 1-axis and 3-axis
AS active probes. The signals from all 3 probes are available simultaneously
and in parallel via the BNC connections or via the terminal contacts.
The AS-Adapter 3 supplies the AS active probes with ± 3 V in a highly stable
manner. The probe signals are amplified with x5 or x50, so that with ± 2 V or ±
0.2 V they can output ± 10 V for a PLC system and Provide oscilloscope.
The wide supply voltage range is 9 VDC to 36 VDC. The signals and supply of
the probes are galvanic isolated from the operating voltage.
The analog output of the AS-adapter 3 is calibrated and thus can be used
e.g. for displaying magnetic pulses in the µs-range (Oscilloscope), recording
of measurements and for field control. The bandwidth of the analog output
reaches from DC to a least 100 kHz. Therefore it is suitable for measuring
both constant magnetic fields and alternating magnetic fields. The actual
usable bandwidth depends on used AS-active probe.
After connecting the desired probe, the measurement can start without
adjusting zero and scale because all AS-active probes are calibrated. Hence
replacement probes can be used at any time.
All of our AS-active probes may be connected to the AS-Adapter 3. This
allows the fast adaptation to different measuring task by simply plugging in a
different probe. Depending on the type of AS-active probe fields from a few
nano Tesla up to 12 Tesla can be measured. Further information can be
found in the data sheet of the AS-active probes.
The AS-Adapter 3 has table feet’s and a DIN rail holder mount for cabinet
device mounting.
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5. Description
Teslameter FM
302 AS-Probe A
dapter
AS-Adapter 3
AS-active
-
probe
operating manual
5.3 Items Supplied
The delivered content depends on the concrete order. It may contained::
- case with replacement battery - 5 m adapter cable for probe connection
- factory calibration certificate - factory calibration certificate
- 1.8 m USB cord - 9 V plug-in power supply unit for
- CD with drivers and control software AS-probe adapter (optional)
- power adapter (optional)
- top hat rail adapter fixed to the device
(optional) - 3 pieces 5 m adapter cable for probe
connection
- factory calibration certificate
- factory calibration certificate - 9 V plug-in power supply unit for
- zero chamber (optional) AS-probe adapter (optional)
- linearity curve (optional)
- probe extension cord (optional)
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Figure 1 Example of an order of FM 302 with three probes and options
6. Operation
6.1 Introduction
This Operating Manual should be read carefully before measuring
6.2 Safety Notes
instrument is operated for the first time.
Projekt Elektronik GmbH will not be responsible for damage to the
instrument caused by disregarding this Operating Manual. Neither will
responsibility be assumed for consequential damage resulting from
such mishandling of the instrument.
Also before initial operation, the content of the case should be checked for
completeness of the items supplied (see section 5.3 Items Supplied)!
In order to ensure safe operation of the instrument, be sure to observe the
following recommendations:
• The magnetic field meter was tested after manufacture for compliance
with all applicable safety standards and regulations. To preserve this
condition and to ensure safe operation, the user should be sure to
observe all safety notes and cautions included in this Operating Manual.
• Before measurements, check your probe, probe cord, probe housing,
Teslameter housing, AS-Probe Adapter-housing, AS-Adapter 3-housing,
power adapter and power cord for damage.
• If you believe that the instrument cannot be operated safely any longer,
switch it OFF, mark it accordingly and keep it in a manner to prevent
unintentional use.
Safe operation will not be possible if the unit, the probe, any connecting
cable, the battery or the accumulator, power adapter or power cord show
visible damage, or if the unit fails to operate.
• This instrument must not be handled by children!
• Due attention should be given to the accident prevention rules issued by
authorized bodies, especially to any rules concerning electromagnetic
fields.
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6. Operation
6.3 Teslameter FM 302
6.3.1 Controls and Connectors
Housing
2 line LCD display
Keypad
Analog output
Probe connector
Figure 2 Controls and connectors FM 302
Power switch
USB connector
Power input
Battery compartment
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6. Operation
6.3.1.1 Housing
The screwed housing is a plastics material resistant to scratches and
fracture to protect the electronics from outside influence.
6.3.1.2 Handle
The handle swings out of the bottom and can be used to support the
Teslameter FM 302 on a horizontal surface or - if replaced - to suspend it.
6.3.1.3 top hat rail adapter (optional)
With the optionally available top hat rail adapter fix mounted to the
Teslameter FM 302, the device can be mounted to a top hat rail. For release
the locking bar has to be pulled up with a screw driver.
6.3.1.4 Power Switch
On the left side of the Teslameter FM 302 is a sliding switch to switch it on
and off.
6.3.1.5 Keypad
The Teslameter FM 302 has a keypad which allows to control major device
functions. For the usage of the single keys see section 6.3.1.7 to 6.3.1.14.
Figure 3 Keypad of Teslameter FM 302
The control with the keypad can be locked with a command via the USB
interface (see section 6.3.3.14 Command “keys). After switching the device
off and on again, the keys are unlocked.
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6. Operation
6.3.1.6 Display
The Teslameter FM 302 has a two-line LCD display.
After power on the device initializes itself. During that the display shows the
manufacturer and device name.
Afterwards the display shows the device number / serial number and the
firmware version.
Figure 4 Display of Teslameter FM 302
Figure 5 Display of serial number and firmware version
Figure 6 Display of Teslameter FM 302
In the upper line on the left side it is shown if DC fields or AC fields are
measured.
Next to it the current measured value is displayed 4½ -digit. In measuring
mode DC that is the mean value of the probe signal. In AC the effective
value (true RMS) of the alternating component of the probe signal is
displayed. See also section 6.3.1.8 Key “DC AC” – Measuring Mode.
Positive measurement results are displayed without a sign.
Rightmost the unit of the measured value is displayed. The unit can be
switched between Tesla, Gauss, Oersted and A/m. See also section
6.3.1.10 Key “unit” – Unit.
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6. Operation
The prefix of the unit and the resolution and consequently the position of the
decimal point of the measured value are derived from the sensitivity of the
connected probe and the selected measuring range.
If no probe is connected to the device, the display shows “no probe“ instead
of measured value and unit.
Figure 7 Display without probe
If the measured value is to large for the selected measuring range the
display shows “overload”.
Figure 8 Display while range overflow
In the lower line of the display in absolute measurement left the currently
selected range is displayed. See also section 6.3.1.9 Key “gain” –
Measuring Range to change the measuring range.
In the lower left the state of the power supply of the Teslameter FM 302 is
displayed. A full battery symbol denotes, that the Teslameter FM 302 is
running on battery and that the voltage of the battery is sufficient to power
the device. An empty battery symbol signalizes that the voltage of the
battery has run significantly low and the battery should replaced (see section
8.2 Checking Battery and 8.3 Maintaining Accumulators).
Figure 9 Display battery state
If the Teslameter FM 302 is powered with a power adapter “EXT” is shown
instead of the battery symbol. If the device is connected via USB and is
powered via the USB connection the display shows “USB”.
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6. Operation
Figure 10 Display supply by power adapter or USB
In the measuring modes relative measurement, minimal measurement and
maximal measurement the lower line shows the measuring mode in the left
and the reference value or minimal or maximal value with unit in the right.
If the Teslameter FM 302 runs on battery as power supply and if the battery
is nearly empty, instead of the unit, the empty battery symbol is shown in
lower right.
The update rate of the display is determined by the setting of the measuring
time. Each time the measuring time has passed a new measured value is
available and printed out at the display. To set the measuring time see
section 6.3.1.13 Key “time” – Measuring Time.
6.3.1.7 Key “zero” – Offset Compensation
The Teslameter FM 302 offers the possibility to compensate an offset of the
zero point. The compensation range is > ±1/10 of the most sensitive
measuring range. With a measuring range of 2 mT that means a
compensation range of > ±200 µT. With this function a deviation of the zero
point caused by temperature change of sensor and electronic can be
removed.
The possibility to compensate the offset is only available in the measuring
mode DC.
After pressing the key “zero” the device automatically performs the
compensation. The message “zeroing” is displayed and a number of dots
shows the progress of the compensation process.
Figure 11 Display while offset compensation process
If the offset is larger than the compensation range, the error message “offset
out of range” is displayed. The compensation is reset to zero.
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6. Operation
Figure 12 Display error message offset out of range
To reset the compensation to zero, the key “zero” has to be pressed a
second time while the compensation process is running. The FM 302
confirms the reset of the compensation with the message “reset zero to
midscale”.
Figure 13 Display reset offset compensation
There are two possibilities to compensate the zero point.
• At the AS-UAP probes in the less sensitive range and all other AS-
probes in the most sensitive range and measuring mode DC the
measuring direction of the probe is positioned orthogonal to the earth
magnetic field in east-west direction. With the “zero” key a compensation
of the zero point is performed. Afterwards the probe should show the
same value only differing in the sign if aligned in north-south and southnorth direction. The typical value of the earth magnetic field in the area of
Europe is 30 µT to 50 µT.
• If a zero chamber is at hand after inserting the probe the offset
compensation can be performed by pressing the “zero” key.
The offset compensation is an additive correction which doesn’t have an
impact on the linearity.
See also section 6.3.3.24 Command “zero” for controlling the offset
compensation via the USB interface.
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6. Operation
6.3.1.8 Key “DC AC” – Measuring Mode
With the key “DC AC” the measure mode is switched between DC field and
AC field measurement. Correspondingly the coupling is switched. The
selected measuring mode is shown in the upper left of the display.
Figure 14 Display measuring mode
DC: The LCD display shows the arithmetic mean of the magnetic field
signal.
The signal of the magnetic field in the frequency range from 0 to
100 kHz (-3 dB) is available at the analog output.
AC: In this position the true effective value (true RMS) of an overlaying
alternating field in the range of 5 Hz to 100 kHz (-3 dB) is displayed.
The analog output provides the time response of the overlaying AC-
field in the range of 5 Hz to 100 kHz.
For the time response of the display and the analog output see section
6.3.2.1 Time Response of Display and Analog Output.
See also section 6.3.3.7 Command “coupling” for controlling the measuring
mode via the USB interface.
6.3.1.9 Key “gain” – Measuring Range
With the key “gain” the measuring range can be selected. There are
available the three ranges B3, B2 and B1. These correspond to a sensitivity
of x1, x10 and x100 of the analog signal. The selected measuring range is
shown in the lower left of the display.
To which measuring range the ranges B1, B2 and B3 correspond can be
read on the imprint of the connector housing of the probe. According to the
chosen range the decimal point and the unit prefix is set at the display.
The chosen range determines the sensitivity of the display and the analog
output.
See also section 6.3.3.12 Command “gain” for controlling the measuring
range via the USB interface.
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6. Operation
6.3.1.10 Key “unit” – Unit
With the key “unit” the unit to display the measured value can be selected.
One can choose from the units Tesla, Gauss, Oersted and A/m. Every key
press cyclically chooses the next unit.
The prefix of the display unit is automatically set depending on the type of
the connected probe and the chosen measuring range.
For exemptions see section 6.3.2.6 Display of Units with older AS-ActiveProbe.
See also section 6.3.3.22 Command “unit” for controlling the unit via the
USB Interface.
6.3.1.11 Key “rel abs” – Relative Measurement
With this key the measuring mode is set to relative measurement. With
pressing the key, the current measured value is taken as reference value
and shown with unit in the lower line of the display.
From now on the measured values in the upper display line are shown
relative to this reference value.
Figure 15 Display in relative measurement
relative value = absolute value – reference value
If the key is pressed again, the Teslameter FM 302 switches back to the
measuring mode absolute measurement.
The relative measurement has no influence on the analog output of the
Teslameter FM 302. The analog output always delivers the current absolute
signal.
See also section 6.3.3.19 Command “relative” and 6.3.3.6 Command
“absolute” for switching between absolute measurement and relative
measurement via the USB interface.
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6. Operation
6.3.1.12 Key “min max” – Minimal Measurement, Maximal Measurement
With this key it is switched cyclically between the measuring modes minimal
measurement, maximal measurement and absolute measurement.
In minimal measurement the upper display line shows still the current
measured value while the lower line displays the smallest value since start
of the measuring mode.
Figure 16 Display in minimal measurement
In maximal measurement the upper display line shows still the current
measured value while the lower line displays the greatest value since start
of the measuring mode.
Figure 17 Display in maximal measurement
The minimal measurement or maximal measurement has no influence to on
analog output of the Teslameter FM 302. The analog output always delivers
the current absolute signal.
See also section 6.3.3.17 Command “minimum”, 6.3.3.16 Command
“maximum” and 6.3.3.6 Command “absolute” for switching between minimal
measurement, maximal measurement and absolute measurement via the
USB interface.
6.3.1.13 Key “time” – Measuring Time
With the key “time” the measuring time is set. This also sets the update rate
of the display. Each time the measuring time has passed a new measured
value is available and printed out at the display.
The internal sample rate of the Teslameter FM 302 is 10 Hz. From the
samples taken during the measuring time, the measured value is computed.
So a longer measuring time reduces the noise of the measured values.
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6. Operation
With the key “time” the measuring times 100 ms, 200 ms, 500 ms, 1 s 2 s
and 5 s can be set.
A short press of the key displays the currently set measuring time.
Subsequent presses cyclically rise the measuring time.
Figure 18 Display measuring timeout
After a fast change of the flux density it is advisable to wait filter x time
before using the measured value.
The setting of the measuring time has no influence on the analog output of
the Teslameter FM 302. The analog output always delivers the unfiltered
absolute signal with full bandwidth.
See also section 6.3.3.13 Command “inttime” or “time” for extended
possibilities for controlling the measuring time via the USB interface.
6.3.1.14 Key “filter” – Filter
With the key “filter” an additional moving average filter of selectable length
can be activated. As the filter works moving about the measured values, the
update rate of the display is kept unchanged.
With the key “filter” a filter length of 1 (filter off) 2, 4, 8, 16, 32 or 64
measured values can be set. A larger filter length results in less noise of the
measured values.
A short press of the key displays the currently set filter length. Subsequent
presses cyclically rise the filter length.
Figure 19 Display filter length
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6. Operation
After a fast change of the flux density it is advisable to wait filter x time
before using the measured value.
The setting of the filter length has no influence on the analog output of the
Teslameter FM 302. The analog output always delivers the unfiltered
absolute signal with full bandwidth.
See also section 6.3.3.10 Command “filter” for extended possibilities for
controlling the measuring time via the USB interface.
6.3.1.15 Acoustic Feedback
Every new setting is acknowledged acoustically by a two-tone. At an error
message the feedback is a disharmonic tone.
See also section 6.3.3.21 Command “sound” for switching acoustic
feedback on and off via the USB interface.
6.3.1.16 Analog Output
The calibrated analog output is a BNC female connector. The output
impedance is 50 Ohm.
With the key “gain” the sensitivity (see section 6.3.1.9 Key “gain” –
Measuring Range) of the analog output is set, too.
The coupling (DC or AC) is determined by the setting of the measuring
mode(see section 6.3.1.8 Key “DC AC” – Measuring Mode).
The settings done with key “time” (see section 6.3.1.13 Key “time” –
Measuring Time) and “filter” (see section 6.3.1.14 Key “filter” – Filter) have
no influence on the analog output. The analog output always delivers the
unfiltered absolute signal with full bandwidth.
Also the measuring modes relative measurement (see section 6.3.1.11 Key
“rel abs” – Relative Measurement) as well as minimal measurement and
maximal measurement (see section 6.3.1.12 Key “min max” – Minimal
Measurement, Maximal Measurement) do not influence the analog output.
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6. Operation
The output voltage range is ±2.3 V. The transfer factor depends on the set
measuring range. For example a measuring range of 2000 mT results in a
transfer factor of 1 V/T.
6.3.1.17 Probe Connector
The AS-active-probes will be connected to this connector. Thereby the
probes should also be screwed. To connect / disconnect the probe the
Teslameter FM 302 should be switched off.
Plugging in the AS-UAP-probe care should be taken not to mechanically
stress the control elements at the probe connector.
If no AS-probe is connected to the Teslameter FM 302 the display shows
“no probe”“ (see also section 6.3.1.6 Display).
6.3.1.18 USB Interface
The Teslameter FM 302 offers a USB interface compatible to USB 1.1 and
USB 2.0.
To this port a USB cord with type B plug can be connected to connect the
Teslameter FM 302 with a PC. A suited cable is included in delivery (see
also section 5.3 Items Supplied).
Via the USB interface the Teslameter FM 302 may be controlled and the
measured values read out (see also section 6.3.3 USB Interface). . Also the
device can be powered via the USB connection so the battery is preserved
and there is no need for a power adapter.
6.3.1.19 Power Connector
If the instrument is powered externally, it is supplied with 9 V through this
connector. (see section 6.3.2.4 Power Adapter Operation). The inner port is
the negative supply voltage.
6.3.1.20 Battery Compartment
The battery compartment houses the 9 V battery or a 9 V accumulator (see
section 8.2 Checking Battery and 8.3 Maintaining Accumulators).
To open the battery compartment the cap at the rear of the device is drawn
away.
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6. Operation
6.3.2 Usage of The Teslameter FM 302
Usually the AS-active-probe is simply connected to the Teslameter. The
Measurement can be started immediately.
Also all extended possibilities of the Teslameter FM 302 are usable in that
way. The calibrated analog output can be connected with e.g. with an
oscilloscope to display fast signal sequences A cable with BNC connector
has to be used.
To control via USB interface the FM 302 has to be connected to the
computer. The connection also can be made to a USB hub. Therefore an
ordinary cable with USB-B connector has to be used. Such a cable is
included in delivery.
Figure 20 Usage of Teslameter FM 302
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6. Operation
To power the device externally a 9 V power supply can be uses. A suitable
power adapter may optionally ordered with the FM 302. Alternatively the
device can be powered via the USB connection. See also section 6.3.2.2
Power Supply.
6.3.2.1 Time Response of Display and Analog Output
Mode: DC AC
Figure 21 Time response
For the upper bandwidth see the technical date of the probe (see section 7.2
Technical Specifications - AS-Active-Probes).
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6. Operation
6.3.2.2 Power Supply
The Teslameter FM 302 may be powered by three different ways. The
device can run from an internal battery / accu (see section 6.3.2.3 Battery /
Accumulator Operation), an external 9 V power adapter (see section 6.3.2.4
Power Adapter Operation) or from the USB connection (see section 6.3.2.5
USB Operation).
The instrument automatically is powered from the power adapter or, while
available, the USB connection and uses the battery only if no other power
source is available. So the battery is preserved.
The switching between the different sources is done automatically and
without interrupting the operation of the device.
The state of the power supply is shown in the display of the Teslameter
FM 302 (see also section 6.3.1.6 Display).
6.3.2.3 Battery / Accumulator Operation
− Open the case (printed lettering up) and remove the Teslameter
FM 302.
− Take the desired probe, connect to Teslameter FM 302 and screw.
− At the AS-NTP 0,6 probe unscrew and remove the protective cap. At the
AS-NTP-Flex probe and AS-NTP-Hot-05 probe careful draw of the
protective cap.
− Switch the instrument ON with the power switch on the left hand side
(see section 6.3.1.4 Power Switch).
− Set the desired parameters with the keys of the keypad. Especially set
the appropriate measuring range with key “gain” (see section 6.3.1.9 Key
“gain” – Measuring Range and measuring mode DC or AC/RMS with key
“DC AC” (see section 6.3.1.8 Key “DC AC” – Measuring Mode.
− The magnetic field can now be measured with the probe.
− The battery life (operating time) is approx. 20 hours, depending on the
probe type.
6.3.2.4 Power Adapter Operation
− Open the case (printed lettering up) and remove the Teslameter FM 302
and the power adapter.
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6. Operation
− Take the desired probe, connect to Teslameter FM 302 and screw.
− Plug the power adapter into a 230 VAC mains socket.
− Plug the small plug from the power adapter into the 9 V-power connector
at the lower left side of the Teslameter FM 302 (see section 6.3.1.19
Power Connector).
− At the AS-NTP 0,6 probe unscrew and remove the protective cap. At the
AS-NTP-Flex probe and AS-NTP-Hot-05 probe careful draw of the
protective cap.
− Switch the instrument ON with the power switch on the left hand side
(see section 6.3.1.4 Power Switch).
− Set the desired parameters with the keys of the keypad. Especially set
the appropriate measuring range with key “gain” (see section 6.3.1.9 Key
“gain” – Measuring Range and measuring mode DC or AC/RMS with key
“DC AC” (see section 6.3.1.8 Key “DC AC” – Measuring Mode.
− The magnetic field can now be measured with the probe.
6.3.2.5 USB Operation
− Open the case (printed lettering up) and remove the Teslameter
FM 302.
− Take the desired probe, connect to Teslameter FM 302 and screw.
− Connect the USB port of the Teslameter FM 302 (see section 6.3.1.18
USB Interface) and the USB port of the PC with a USB cord.
− At the AS-NTP 0,6 probe unscrew and remove the protective cap. At the
AS-NTP-Flex probe and AS-NTP-Hot-05 probe careful draw of the
protective cap.
− Switch the instrument ON with the power switch on the left hand side
(see section 6.3.1.4 Power Switch).
− Set the desired parameters with the keys of the keypad or the USB
commands. Especially set the appropriate measuring range with key
“gain” (see section 6.3.1.9 Key “gain” – Measuring Range and measuring
mode DC or AC/RMS with key “DC AC” (see section 6.3.1.8 Key “DC
AC” – Measuring Mode.
− The magnetic field can now be measured with the probe.
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6. Operation
6.3.2.6 Display of Units with older AS-Active-Probe
The AS-active-probes are coded with information to display the measuring
range and unit. To, in contrast to the Teslameter FM 205, show not only the
unit Tesla but also Gauss, Oersted and A/m at the Teslameter FM 302 an
extension of that coding was necessary. Since September 2011 the ASactive-probes have the extended coding.
At the AS-active-probes without extended coding, the Teslameter FM 302 is
unable to distinct between probes for the low and probes for the ultralow
range. Therefore instead of a unit “??” is displayed. Switching the unit via
key or interface command is not possible in that case, too.
Figure 22 Display with not representable unit
The display of the decimal point however is correspondent to the ranges of
the probes. The information about the unit can be found, like at the
Teslameter FM 205, at the imprint of the probe.
The AS-active-probes for normal or high range with production date before
September 2011 are not affected by this problem.
AS-active-probes with older production date may be upgraded with the
extended coding.
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6. Operation
6.3.3 USB Interface
6.3.3.1 General
The USB interface of the Teslameter FM 302 is realized with the FT232R, a
USB-to-serial converter from Future Technology Devices International Ltd.
(FTDI, http://www.ftdichip.com/).
That means, that the Teslameter FM 302 creates a virtual serial port after it
has been connected to a PC. For communication every ordinary terminal or
terminal program is suited. The control takes place text oriented which
makes it easy to integrate the Teslameter into existing environments.
The necessary USB driver can be found at the CD which is included in
delivery (see also section 5.3 Items Supplied). The newest drivers can be
found at the homepage of FTDI under the menu Drivers – VCP Drivers
(http://www.ftdichip.com/Drivers/VCP.htm).
6.3.3.2 Driver Installation Windows
Windows 7 and above contain the driver for the FTDI chip. Connect the
instrument to a free USB port of your computer. Windows automatically
detects the new device and installs the driver. This may take a moment.
Alternatively the driver from the included CD or from the website of FTDI can
be used.
Further installation guides for different versions of Windows are available (in
English language) at the homepage of FTDI.
(http://www.ftdichip.com/Support/Documents/InstallGuides.htm)
6.3.3.3 Driver Installation Linux
Linux contains the necessary drivers since kernel version 2.6.31. A separate
driver installation is not necessary.
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6. Operation
6.3.3.4 Configuration of the Virtual Serial Port
To communicate with the Teslameter FM 302 the virtual serial port has to be
configured as follows.
baud rate 9600
data bits 8
parity none
stop bits 1
flow control non
6.3.3.5 General about Commands
The Teslameter FM 302 has a simple command structure consisting of the
command name followed by one optional parameter. Command and
parameter are separated by a space. Supplementary whitespaces will be
tolerated. Every command line is finished with a newline character
(LF/10d/0Ah). A preceding carriage-return character (CR/13d/0Ch) will be
tolerated too.
All commands (but not the parameters) may abbreviated as long as they are
distinguishable. The commands are not case-sensitive.
typographic convention of the examples:
normal script output FM 302
bold script input user
[ ] optional-brackets; brackets are not entered
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6. Operation
absolute
coupling
coupling AC
default
6.3.3.6 Command “absolute”
command: absolute
without
parameter
see also section 6.3.1.11 Key “rel abs” – Relative Measurement
example:
display is absolute
6.3.3.7 Command “coupling”
command: coupling [{DC|AC}]
without
parameter
with parameter switches to selected measuring mode
parameter DC, AC
see also section 6.3.1.8 Key “DC AC” – Measuring Mode
examples:
switches to absolute measurement
shows the currently set measuring mode / coupling.
coupling is DC
coupling is AC
6.3.3.8 Command “default”
command: default
without
parameter
example:
factory settings restored
reset instrument to factory configuration
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6. Operation
digits
digits
1
filter
filter 10
6.3.3.9 Command “digits”
command: digits [digits]
without
parameter
with parameter blinds out given number of decimals
parameter 0, 1
examples:
decimals blinded out 0
decimals blinded out 1
6.3.3.10 Command “filter”
command: filter [taps]
without
parameter
with parameter sets filter length to given value
parameter 1 ≤ taps ≤ 64
see also section 6.3.1.14 Key “filter” – Filter
examples:
shows number of blinded out decimals
shows current filter length
filter is 5
filter is 10
6.3.3.11 Command “fmstatus” or “status”
command: fmstatus
status
without
parameter
shows the list of current settings
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6. Operation
status
gain
gain 10
example:
FM 302 status
------------serial no. is 1106827001
firmware version is V1.0, built Sep 8 2011, 13:10:34
coupling is DC
analog gain is x1
unit is T
range is 2000.0 mT
integration time is 500 ms
filter is 5
decimals blinded out 1
zero compensation value is 0
sound is on
keys are unlocked
external offset is 400000
external slope is 0
factory offset is 0
factory slope is 25100
factory calibration active
6.3.3.12 Command “gain”
command: gain [{1|10|100}]
without
parameter
with parameter sets the measuring range to the given sensitivity
parameter 1, 10, 100
see also section 6.3.1.9 Key “gain” – Measuring Range
examples:
shows current sensitivity
analog gain is x1
analog gain is x10
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6. Operation
time
time 1250
keys
keys off
6.3.3.13 Command “inttime” or “time”
command: inttime [time]
time [time]
without
parameter
with parameter sets the measuring time to the given value (interpreted
parameter 100 ≤ time ≤ 25500
see also section 6.3.1.13 Key “time” – Measuring Time
examples:
integration time is 500 ms
integration time is 1300 ms
6.3.3.14 Command “keys”
command: keys [{on|off}]
without
parameter
with parameter switches keypad on (unlocked) or off (locked)
parameter on, off
examples:
shows the current measuring time in milli-seconds
as milli-seconds, rounded to a multiple of 100 ms)
shows if the keypad is locked or not
After switching the device off and on again, the keys are
unlocked.
keys are unlocked
keys are locked
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6. Operation
logging
logging 2
maximum
6.3.3.15 Command “logging”
command: logging [{number|off|on}]
without
parameter
with parameter The parameter “on” switches to permanent logging.
parameter on, off, 1 ≤ number ≤ 65534
examples:
logging is on
1462.7 mT
1462.1 mT
logging off
logging is off
logging 2 records
1247.0 mT
1248.7 mT
6.3.3.16 Command “maximum”
switches between permanent logging and no logging
The parameter “off” deactivates a running logging.
Also the number of values to log may be given
command: maximum
without
parameter
see also section 6.3.1.12 Key “min max” – Minimal Measurement, Maximal
Measurement
example:
display is max
switches to maximal measurement
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6. Operation
minimum
range
6.3.3.17 Command “minimum”
command: minimum
without
parameter
see also section 6.3.1.12 Key “min max” – Minimal Measurement, Maximal
Measurement
example:
display is min
6.3.3.18 Command “range”
command: range
without
parameter
example:
range is 2000.0 mT
6.3.3.19 Command “relative”
switches to minimal measurement
shows the current measuring range determined by probe
and gain setting
command: relative [{reference|set}]
without
parameter
with parameter “set” as parameter switches to relative measurement
show the current measuring mode and if in relative
measurement the reference value
and takes the current measured value as reference
value.
A number as parameter switches to relative
measurement and uses the given number as reference
(interpreted in the currently set unit and rounded to the
current resolution).
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6. Operation
relative
relative set
relative 1.2
706
relative
parameter „set“ or a reference value
The given reference value may not exceed the display
range of the Teslameter FM 302 of 25100 digit. Float
point numbers with “.” as decimal separator and
numbers in scientific notation (e.g. 12E-2) are accepted.
see also section 6.3.1.11 Key “rel abs” – Relative Measurement
examples:
display is relative, reference = 1247.8 mT
display is relative, reference = -23.3 mT
display is relative, reference = 1.3 mT
unit Gs
unit is Gs
relative 1.2706
display is relative, reference = 1.271 kGs
6.3.3.20 Command “serial”
command: serial
without
parameter
example:
serial no. is 1109827002
shows the serial number of the device
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6. Operation
sound
sound off
unit
unit a/m
6.3.3.21 Command “sound”
command: sound [{on|off}]
without
parameter
with parameter switches acoustic feedback on or off
parameter on, off
see also section 6.3.1.15 Acoustic Feedback
examples:
sound is on
sound is off
6.3.3.22 Command “unit”
command: unit [{T|G|Gs|Oe|A/m}]
without
parameter
with parameter sets unit to given unit
parameter T, G, Gs, Oe, A/m
see also section 6.3.1.10 Key “unit” – Unit
exceptions see section 6.3.2.6 Display of Units with older AS-Active-Probe.
examples:
shows if acoustic feedback is activated or deactivated
shows currently set unit
The unit prefix of the display is automatically set
depending on the probe and selected measuring range
unit is T
unit is A/m
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6. Operation
version
zero
zero set
zero -
12345
6.3.3.23 Command “version”
command: version
without
parameter
example:
firmware version is V1.0, built Sep 8 2011, 13:10:34
6.3.3.24 Command “zero”
command: zero [{offset|set}]
without
parameter
with parameter With “set” as parameter the automatic offset
parameter set, -39320 ≤ offset ≤ 26213
see also section 6.3.1.7 Key “zero” – Offset Compensation
examples:
shows the version of the installed firmware
shows the current value of the offset compensation
compensation process is started.
If a number is given as parameter, it is taken as new
value for the offset compensation. The exact transfer
factor is device dependent.
zero compensation value is -7365
zeroing.....
zero compensation value is 10610
zero compensation value is -12345
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6. Operation
6.3.4 Control Software FM 302 Control
Figure 23 Control software FM 302 Control
6.3.4.1 General Description
Included in delivery is a control software for the Teslameter FM 302. The
software allows to control all settings of the Teslameter via the PC. Thereby
the software not only allows to control the settings accessible via the keypad
of the device, but offers the complete range of functions which are possible
with the commands via the USB interface.
The software runs on all platforms where the Microsoft .NET Framework 4.0
is available. Currently (September 2011) that are all Windows version from
Windows XP on.
Detailed information are available at http://msdn.microsoft.com/enus/library/bb882520.aspx
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6. Operation
The provided source code demonstrates the software control of the device
and can be used as a base for the development of an own software.
All in all the software is given as a demo only. The usage in a productive
environment is done at your own risk.
6.3.4.2 Installation
The software FM 302 Control is delivered with a ClickOnce installation
routine. To install the software the setup.exe has to be executed which
can be found at the CD in the folder D:\FM 302 Control\ and there in
the subfolder with the current version. The installation runs automatically
and starts FM 302 Control afterwards.
To run the software the Microsoft .NET Framework 4.0 is necessary. If that
is not available at the computer, it is automatically installed by the
installation routine too.
During installation an entry in the start menu is created so for later use the
software can be started via Start → program → Projekt Elektronik GmbH →
FM 302 Control.
6.3.4.3 Connection to Teslameter FM 302
To use the software FM 302 Control the Teslameter FM 302 has to be
connected to the USB port of the PC.
After the start of FM 302 Control select the virtual serial port created by the
FM 302 in the drop down box in the upper right. Then click “Connect” to
establish the connection. If the Teslameter is connected to the PC after the
software has been started, the new interface will appear automatically in the
list after a few moments.
If the connection was established successfully the other controls of the
software are enabled. The currently set parameters of the Teslameter
FM 302 are read out and the selection fields are preset with these values.
Furthermore the firmware version and the serial number of the FM 302 are
shown.
The graphical user interface of FM 302 Control clearly shows the extended
possibilities of the USB interface commands.
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6. Operation
6.3.4.4 Display and Setting of parameters
The software has a display field whose design is based on the display of the
real device. Like at the device the current measured value plus the
measuring mode and its value are displayed. Additionally the measuring
range (“range”) is shown which is defined by the connected probe and the
sensitivity set at the FM 302.
Figure 24 Value display of the control software
With checking “keyboard” and “sound” the keypad respectively the acoustic
feedback can be activated/deactivated.
Figure 25 Control of keypad lock and acoustic feedback
We recommend to always lock the keypad of the Teslameter while
using the control program. This prevents from making settings at the
device which maybe are not reflected correctly by the control software.
In the drop down boxes the corresponding parameter is set. Therefor one of
the preset values may be chosen or where permitted an arbitrary value (in
the defined borders) may be entered. Selected values are taken
immediately. Values entered with the keyboard are taken when the cursor
leaves the input field (e.g. by clicking into an other field). The input field will
be updated with the value actually confirmed by the FM 302. For the exact
function and the value range of the parameters see the descriptions in
section 6.3.3 USB Interface.
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6. Operation
Figure 26 Control of the FM 302 settings
6.3.4.5 Oscilloscope Display
Besides the simple display of the measured value the software offers an
oscilloscope-like display of the last 100 measured values. The time axis
depends on the selected measuring time. The used scaling is displayed
below the diagram.
The scale of the amplitude axis is given by the connected probe and the
selected sensitivity of the FM 302. It covers the full range of values possible
in the set configuration. In measuring mode relative measurement the
baseline is moved corresponding to the set reference value. See also
section 6.3.1.11 Key “rel abs” – Relative Measurement and section 6.3.3.19
Command “relative.
To better display the change of small values the box “x10” below left at the
display can be check. This reduces the displayed value range to one tenth
what produces a display ten times more sensitive.
By pressing the button “save image” the current image will be saved. The
file format can be chosen from the formats JPEG, PNG, BMP, TIFF, GIF
and EMF.
For the display the values are taken from the digital sampling. With
minimum measuring time of 0.1 s the maximal possible sampling rate
is 10 Hz. For displaying faster signals a real oscilloscope can be
connected to the analog output of the Teslameter FM 302.
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6. Operation
Figure 27 Oscilloscope-like display
6.3.4.6 Logging of Measured Values
The control software not only permits to display the measured values of the
FM 302 but also to save them into a log file. There are two different modes
and two different file formats to chose from. The selection can be made in
the section “logging”.
Figure 28 Setting logging parameter
It is always stored one measured value per line with the current time stamp
with 0.1 s resolution, the current measured value and its unit. If one of the
measuring modes relative measurement, maximal measurement or minimal
measurement is active the corresponding mode abbreviation and the
corresponding reference or measured value and its unit is also stored.
Below is printed an extract from a log file as an example. The measured
values are chronological one below the other. The last measured value is at
the lowest line.
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6. Operation
For storing the log file there can be chosen from two different formats The
log can be saved in classic csv format (comma separated values). In this
format the single data blocks are separated by a comma. The period is used
as decimal separator. Alternatively the semicolon may be used for
separating the data blocks which makes available the comma as decimal
separator. The second format simplifies the import into software with
German localization.
The created log files can easily be imported to every common program for
data evaluation like Microsoft Excel, OpenOffice Calc, Mathlab or gnuplot.
This allows to individually evaluate and process the measured data.
Depending on the selection in the logging settings, the corresponding
logging section is enabled.
In the mode “single value logging” single measured values can be saved
with a key press (mouse or keyboard). At every press of the button “log
value” the current measured value is stored to the log. This mode is suitable
for manual controlled measurements where a number of single values has
to be measured.
2012-03-28 12:48:39,0; 0,67; mT; min; -0,81; mT
2012-03-28 12:48:39,5; 0,57; mT; min; -0,81; mT
2012-03-28 12:48:40,0; -1,47; mT; min; -0,81; mT
2012-03-28 12:48:40,5; -7,33; mT; min; -1,47; mT
2012-03-28 12:48:41,0; -19,95; mT; min; -7,33; mT
2012-03-28 12:48:41,5; -35,88; mT; min; -19,95; mT
2012-03-28 12:48:42,0; -51,29; mT; min; -35,88; mT
2012-03-28 12:48:42,5; -46,67; mT; min; -51,29; mT
2012-03-28 12:48:43,0; -23,17; mT; min; -51,29; mT
2012-03-28 12:48:43,5; 5,86; mT; min; -51,29; mT
Figure 29 Log file example
Figure 30 Single value logging
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6. Operation
In contrast in the mode “continuous value logging” the measured value are
automatically stored continuously into the log. This mode is suitable to
record traces over longer periods of time.
A click on the button “start” starts the recording of measured values. With a
click on “stop” the recording is halted. By clicking “start” again the logging
can be continued. The new measured values are appended to the existing
log.
To reduce the amount of data at long time recordings it is possible to write
only every x-th value to the log. X can be set between 1 (take every
measured value) and 10,000. The logging cycle given by measuring time
and setting of x is displayed at the window. In that way intervals between
100 ms and barely 3 days can be set.
By checking the check box “log overload” it can be determined if an
“overload” is written to the log file in case of exceeding the measuring range
or if no value is logged in this case.
Figure 31 Continuous value logging
Switching between the modes “single value logging” and “continuous value
logging” is possible at any time. New measured values are always
appended to the existing log.
The software shows a preview of the log with the last 20 stored values. At
this preview the last logged value is at the top.
With the button “clear log” the existing log can be erased.
With the button “save loge” the recorded log can be stored. The log is kept
in the program so it can be continued afterwards.
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6. Operation
6.3.4.7 Limit Comparator
Furthermore, the software offers a limit comparator function. Here an upper
and a lower limit can be defined. Thereupon the software shows if the
current measured value is below the lower limit (“to low”), between the limits
(“OK”) or above the upper limit (“to high”). The corresponding field thereby
changes its color from dark to light.
Figure 32 Log preview
Figure 33 Limit comparator
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6. Operation
The limits are taken in the unit, the current measured value is display in. If
the display unit or the sensitivity is changed or if even the probe is change,
an adjustment of the limits may be necessary in some cases.
The limits may have positive, negative or mixed sign. Greater and less are
taken in the mathematical way where –10 is greater than –20.
The upper limit has to be greater or equal than the lower limit. Otherwise the
software will display a warning message and disable the display of the
relation of the current measured value and the display of the limits in the
oscilloscope display.
If the check box “show in graph” is checked, the limits are shown as colored
dashed lines in the oscilloscope display.
Figure 34 Oscilloscope display with limits of limit comparator
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6. Operation
6.3.4.8 Restore Factory Settings
With “restore defaults” the Teslameter FM 302 can be reset to the factory
settings. Here too see the description in section 6.3.3.8 Command “default”.
6.3.4.9 Uninstall
FM 302 Control can be uninstalled under Start → Settings → Control Panel
→ Add or Remove Programs.
6.3.4.10 Source Code
FM 302 Control was written in Visual Basic 2010 Express.
At the CD in the folder FM 302 Control there is a subfolder with the
current version. In this folder is a subfolder Source which contains the
Visual Basic project with the complete source code. The source may be
used as a base to develop an own software or to integrate in an existing
system.
Figure 35 Reset to the factory settings
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6. Operation
6.4 AS-Active-Probe
6.4.1 Polarity
6.4.1.1 Transverse Probe
Maximum flux density is measured if the lines of magnetic field
perpendicularly traverse the Hall element!
A positive reading is obtained when the lines of magnetic force enter the
white ceramic surface of the flexible transverse probe or the engraved black
cross of the transverse probe brass.
Figure 36 Measurements using a transverse probe
If the lines of magnetic force do not enter the Hall element at right angle, the
displayed value results from the true magnetic flux density according to the
following relation:
B = B
Figure 37 Trigonometric of the measuring arrangement
max
• cos α
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6. Operation
6.4.1.2 Axial Probe
A positive reading is obtained when the lines of magnetic field left the black
end face of the axial probe at right angle.
Figure 38 Measurements using an axial probe
The maximum field value is measured when the lines of magnetic field
extend in parallel with the measuring probe. The perpendicular part of the
flux density is not displayed.
Figure 39 Trigonometric function of the axial probe
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6. Operation
6.4.2 Measuring Arrangement
The outlet flux density of a bar magnet may be measured by plain lay a
transverse probe (as seen right in the image) or by orthogonal place an axial
probe (as seen left in the image) on the magnet.
Reversing the transverse probe does not produce the same value because
the active area of the hall element is not exactly in the center of the probe.
According to the states about polarity of the measured value (see section
6.4.1 Polarity) the axial probe shown in the image would produce a positive
measured value. If the cross of the transverse probe in the image points to
the magnet, this probe also would produce a measured value with positive
sign.
Figure 40 Measuring arrangement bar magnet
The field within a cylindrical coil is measurable with an axial probe. If a probe
is feed into the coil the lines of field are along the probe axis. For the axial
probe that is also the measuring direction. At the transverse probe the lines
of field would be perpendicular to the measuring direction so no useable
measuring signal may be generated. Like at the bar magnet with both probe
types the outlet flux density may be measured.
Here too the polarity (see section 6.4.1 Polarity) of the axial probe shown in
the image will produce a positive measured value. If the cross of the
transverse probe in the image points to the coil, this probe also would
produce a measured value with positive sign.
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6. Operation
Figure 41 Measuring arrangement cylindrical coil
6.4.3 Precision and Repeatability
The flux density is a vector. To measure the exact value of that vector, the
probe has to be highly perpendicular to the direction of the flux density.
For example to measure a flux density of 1 T accurate to 1 mT, the angle
deviation may not be lager than 2.56 °.
To further illustration: At a rotation with a radius of 100 mm this is only a
distance of 4.47 mm.
The repeatability extremely depends on the quality of the mechanically
fixation of the probe.
6.4.4 Winding up of Cables
Cables always should be wound up in a way that no knots or twists occur. To
ease you the winding up of the cable we have collected and mentioned
below some instructions available on the Internet.
• https://www.youtube.com/watch?v=0yPcJD7RVuY
• https://www.youtube.com/watch?v=pEd7ru24Vx0
• https://www.youtube.com/watch?v=3j1Wdc-ymbI
• https://www.popularmechanics.com/technology/how-to/tips/a-solution-for-
tangled-headphones-15413257
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6. Operation
6.4.5 Transverse Probe AS-NTP 0,6
Figure 42 Transverse probe 0,6
The transverse probe has a blue protective cap which have to be unscrewed
before measurement.
Utmost care and attention are needed if magnets have to be measured
that are not mechanically fixed. Clashing poles can destroy the Hall
element!
As the Hall element (ceramic) is very sensitive to pressure or shock,
mechanical stress must be avoided (risk of breakage)!
6.4.6 Transverse Probe Brass AS-NTM, AS-NTM-2, AS-LTM
Figure 43 Transverse probe brass
For fields of B > 20 mT and f > 10 kHz , probes brass should not be
operated for more than 1 min in order to prevent excessive heating of
the brass tube with the Hall element inside!
Attention should be paid to the fact that at the probe a connection exist
between GND, cable shield, plug housing and brass tube. Possibly an
isolated installation of the probe can be necessary to prevent an
unintended connection between measuring ground and protective
earth.
6.4.7 Transverse Probe Hot AS-NTP-Hot-05
Figure 44 Transverse probe Hot
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6. Operation
The transverse probe has a protective cap which have to be drawn off
before measurement.
Only the probe, the handle and the cable are temperature-resistant.
The probe connector with the electronic may only be operated up to
+50 °C.
6.4.8 Transverse Probe Flex AS-NTP-Flex, AS-NTP-Flex 0,6
Figure 45 Transverse probe Flex
Figure 46 Transverse probe Flex 0,6
The transverse probe has a protective cap which have to be drawn off
before measurement.
Only the probe itself is temperature-resistant. The handle, the cable
and the probe connector with the electronic may only be operated up
to +50 °C.
No pressure shall be applied to the hall element (ceramic) because it is
very pressure sensitive (risk of breaking)!
6.4.9 Transverse Probe Wire AS-NCu-Wire
Figure 47 Transverse probe Wire
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6. Operation
The wire probes are very sensitive. The wires of the probe may not be
bend at the element and may not be pulled.
Only the probe itself is temperature-resistant. The handle, the cable
and the probe connector with the electronic may only be operated up
to +50 °C.
No pressure shall be applied to the hall element (ceramic) because it is
very pressure sensitive (risk of breaking)!
6.4.10 Axial Probe AS-HAP, AS-NAP, AS-LAP
Figure 48 Axial probe
6.4.11 Axial Probe AS-UAP GEO-X, AS-UAP Lot
Figure 49 Axial probe AS-UAP GEO-X
Figure 50 Axial probe AS-UAP Lot
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6. Operation
The AS-UAP-active probes are used for measurements of the earth
magnetic field and up to ±200 µT.
The AS-UAP is available in two different types. The AS-UAP GEO-X is
intended for general measurements. Here the probe housing has the
minimal dimensions necessary to keep the sensor. Especially for measuring
the vertical component of the earth magnetic field the AS-UAP Lot has a
weighted tip. Hence the probe can be hold like a plummet at the cable.
Because the earth magnetic field is present everywhere with ca. 50 µT, the
probe has a compensation trimmer to set the base value to zero. So it is
possible to measure in the x10 and x100 more sensitive ranges the changes
of the base value.
This compensation can be switched off, so it is possible to measure
absolute values (without compensation) at any time.
To be able to gain best stability in the 2 µT range the probe should be
switched on for at least 30 minutes.
Figure 51 Controls connector AS-UAP
connector housing switch for compensation
trimmer for compensation
The axis of the compensation trimmer should not be bend to not
damage the axis or the trimmer.
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6. Operation
6.4.12 Usage of the AS-Active-Probes
6.4.12.1 Usage with the Teslameter FM 302
Usually the AS-active-probe is simply connected to the Teslameter. The
measurement can be started immediately.
Figure 52 Usage of AS-active-probe with FM 302
Also all extended possibilities of the Teslameter FM 302 like calibrated analog
output, control via USB interface or power supply with power adapter are
usable in that way. Further details can be found in section 6.3.2 Usage of The
Teslameter FM 302.
6.4.12.2 Usage as Autonomous Transducer
Our AS-active-probes can be operated stand-alone. Therefore they simply
have to be supplied with ± 3 V (± 1 %) with max. 20 mA. The analog output
signal can be feed e.g. into the input of a programmable amplifier of a PLC.
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6. Operation
The pin configuration of the probe is shown in the graphic below. All other
pins are reserved for future use ore are only relevant in combination with the
Teslameter FM 302. These pins have to remain unconnected.
Figure 53 Usage AS-probe at ±3 V
Figure 54 Pin configuration AS-probe at ±3 V
Like shown in the inner structure schematic the output signal at pin 1 is
always referred to the ground signal at pin 2 and 3. This ground and the
supply voltages +3 V (pin 4) and –3 V (pin 5) have to be provided from the
outside.
The AS-active-probes may not be powered with asymmetric voltages.
It should be observed, the in the probe a connection between GND,
plug shield, plug case and cable shield is made. At probes with brass
protective tube, this is also connected to GND. Possibly an isolated
installation of the probe is necessary to prevent an unintended
connection between measuring GND and protective earth.
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6. Operation
Figure 55 Structure AS-active-probe
6.4.12.3 Usage with the AS-Probe Adapter
To simplify the usage of the AS-active-probe as autonomous transducer, the
AS-probe adapter can be used. It provides high stable ±3 V to supply the
probe and amplifies the output signal to ±10 V.
For further details see section 6.6.4 Usage of the AS-Adapter.
6.4.12.4 Usage with the AS-Adapter 3
Up to three AS probes simultaneously can be operated on the AS-Adapter
3. The AS-Adapter 3 ensures the supply of all connected probes.
Further details can be found in chapter 6.6.4 Using the AS-Adapter 3
6.4.13 Zero Chamber (optional)
Optional a zero chamber is attainable for our instruments.
The zero chamber is a one side closed pipe of good magnetic shielding
metal to shield the existing outer field. That is at least the earth magnetic
field. In addition there may be other interfering fields from the environment.
In real world shielding may not be 100 %. A small residual magnetic field
remains inside of the zero chamber.
Figure 56 Zero Chamber
If necessary the zero point of an AS-active-probe may be checked and
adjusted with the help of a zero chamber. Therefor the AS-probe is feed into
the zero chamber. Now one can assume that the magnetic field is sufficient
shielded. With the “zero” key of the Teslameter FM 302 (see section 6.3.1.7
Key “zero” – Offset Compensation) the display may set to zero in the most
sensitive range.
6.4.14 Linearity Curves (optional)
Linearity curves are optionally available for the AS-active-probes. The
linearity curves are used for determining exact field values at up to five
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6. Operation
[ mT ]
0°C
20°C
40°C
temperatures. These three curves serve to determine the deviation of the
measuring instrument for specific field strength and temperature readings so
as to correct the field values displayed. So a measurement accuracy of
0.1% is achievable.
Each AS-active-probe have its own individual linearity curve. If an AS-probe
is replaced, the linearity curve have to be renewed too.
Examples of typical linearity curves can be found at our application note
PE003 – zero chamber.
The linearity curve serves as a test record.
The following illustration shows an exemplary set of linearity curves:
25
∆B
20
15
10
5
0
-5
-10
-15
-20
-25
B
[ T ]
210-1-2
0,2 %
±0,2 mT
Figure 57 Typical linearity curves
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6. Operation
6.5 AS-Probe Adapter
6.5.1 Controls and Connectors
Figure 58 Controls and connections AS-probe adapter
supply voltage inputs
measurement signal output
±3 V for probe supply
GND for probe supply and
probe signal
probe signal input
power LED
gain switch
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6. Operation
6.5.2 Structure
Figure 59 Structure AS-probe adapter
The AS-probe adapter basically consists of two components, the voltage
converter and the amplifier.
The voltage converter has a wide input range which allows to supply the
adapter with any constant voltage between 9 V and 36 V. The voltage
converter also generates a galvanic isolation form the supply voltage. The
potential difference between primary and secondary side is limited to 130 V
by a varistor. Therefore the potential difference during operation should not
exceed 100 V.
The voltage converter generates high stable ±3 V necessary to supply the
AS-active-probes. Furthermore it provides the voltage to supply the rest of
the circuit.
The amplifier boosts the probe signal from ±2 V to ±10 V (gain x5). With a
switch an again ten times higher amplification (x50) can be selected. In this
setting ±0.2 V are converted to ±10 V.
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6. Operation
6.5.2.1 Supply Voltage Inputs
With these inputs the AS-probe adapter is connected to the power supply.
The adapter can be supplied with a DC voltage between 9 V and 36 V.
Since the adapter internally uses a DC/DC converter the current
consumption depends on the supply voltage. The higher the supply voltage,
the lower the current which is drawn by the adapter.
The input is equipped with a inverse polarity protection diode. Furthermore
besides an overvoltage suppressor the input has a protection circuit which
shortens the input in case of permanent overvoltage to protect the circuit. In
this case the also integrated resettable fuse will trigger after a few moments.
The threshold of the protection circuit is ~39 V. To reset the triggered
protection circuit the adapter has to be disconnected from the power supply.
6.5.2.2 Power LED
This LED lights up if the adapter is correctly supplied with power. If the LED
does not light up even though the adapter is connected to power supply
maybe the overvoltage protection circuit has triggered.
6.5.2.3 Probe Supply
At these outputs the ±3 V necessary to supply the AS-active-probe is
available. The outputs deliver a maximum current of 20 mA.
The supply of the probe and the input of the probe signal use the same GND
connection
6.5.2.4 Probe Signal Input
At this input the measurement signal delivered from the probe is connected.
The maximal converted input voltage range is ±2 V with gain x5 and ±0.2 V
with x50.
The supply of the probe and the input of the probe signal use the same GND
connection
6.5.2.5 Measurement Signal Output
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6. Operation
At this output the amplified measurement signal is available. At maximum
amplitude the maximal output current is 2 mA. Correspondingly the load has
to be at least 5 kΩ. For smaller amplitudes the output can deliver even
higher currents.
The outcome of the given current drive capability is that higher capacitive
loads results in a reduction of bandwidth.
Unloaded the amplifier has a bandwidth of >100 kHz whereby even fast
transient signals can be transferred.
6.5.2.6 Gain Switch
With this switch the gain can be switched between x5 (±2 V → ±10 V) and
x50 (±0.2 V → ±10 V).
6.5.3 Adapter Cable
With the AS-probe adapter an adapter cable is delivered. This cable has a
15pol SubD female connector at one site and four single wires at the other
side. Therefore with this cable a AS-active-probe can easily be connected to
the AS-probe adapter.
The cable can be extended at the side of the SubD connector with probe
extension cords as well as at the side of the single wires.
Figure 60 Adapter cable
The assignment of the single wires to the corresponding pins of the probe and
the connectors of the AS-probe adapter can be found in the table below.
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6. Operation
wire color
probe function
connector adapter
white probe signal IN ±
yellow +3 V ±3V +
green -3 V ±3V brown ground IN ┴
Table 1
One should be aware, that the probes and all outputs have a common
ground. Especially when using the brass version of AS-probes (ASNTM, AS-LTM) an isolation between probe and other parts of the
measurement setup can be necessary.
6.5.4 Usage of the AS-probe adapter
To use the AS-probe adapter three connections have to be made.
At first the AS-active-probe is connected via the delivered adapter cable with
the connectors “±3V” and “IN” of the AS-probe adapter.
For connection assignment of the adapter cable see Fehler! Verweisquelle
konnte nicht gefunden werden. on page Fehler! Textmarke nicht
definiert..
For power supply the input “PWR” has to be connected to a power supply
which delivers a DC voltage between 9 V and 36 V.
As third the output “OUT” has to be connected with the analog input of a
data acquisition system like e.g. a PLC.
The gain switch is set to the desired position (x5 or x50).
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Figure 61 Connection AS-probe adapter
6. Operation
6.6 AS-Adapter 3
6.6.1 Controls and Connectors
Figure 62 Controls and connectors AS-Adapter 3
Power LED
Clamping contacts for Power
and PE
Bridge for connection of
Ground connection and GND
Clamping contacts for input signals
IN X, IN Y, IN Z
6.6.2 Overview of Controls and Connections
The AS adapter 3 consists of two components, the voltage converter and the
amplifiers.
The voltage converter has a wide-range input whereby the AS adapter 3 can
be supplied with an operating voltage range of 9 VDC to 36 VDC. The signals
and supply of the probes are galvanically isolated from the operating voltage.
Clamping contacts for output
signals X, Y, Z
gain switch
BNC Sockets output signals
OUT X, OUT Y, OUT Z
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6. Operation
The potential difference between the primary and secondary side is limited to
130 V by a varistor.
Therefore, the potential difference in operation should not become greater than
100V.
The AS-Adapter 3 supplies the AS active probes with ± 3 V in a highly stable
manner. The probe signals are amplified with x5 or x50, so that with ± 2 V or ± 0.2
V they can output ± 10 V for a PLC system and Provide oscilloscope.
The AS adapter 3 offers the possibility of a separate connection of a PE
conductor. Furthermore, a connection between GND and the ground terminal of
the housing can be made by means of a bridge.
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6. Operation
Figure 63 Structure AS-Adapter 3
6.6.2.1 Supply Voltage Inputs
With these inputs the AS-probe adapter is connected to the power supply.
The adapter can be supplied with a DC voltage between 9 V and 36 V.
Since the adapter internally uses a DC/DC converter the current
consumption depends on the supply voltage. The higher the supply voltage,
the lower the current which is drawn by the adapter.
The input is equipped with a inverse polarity protection diode. Furthermore
besides an overvoltage suppressor the input has a protection circuit which
shortens the input in case of permanent overvoltage to protect the circuit. In
this case the also integrated resettable fuse will trigger after a few moments.
The threshold of the protection circuit is ~39 V. To reset the triggered
protection circuit the adapter has to be disconnected from the power supply.
6.6.2.2 Power LED
This LED lights up if the adapter is correctly supplied with power. If the LED
does not light up even though the adapter is connected to power supply
maybe the overvoltage protection circuit has triggered.
6.6.2.3 Probe Supply
At these outputs, the AS-active probes required for supply are ± 3 V highly
accurate. The outputs deliver a maximum current of 20 mA per AS-active
probe.
The supply for the probes and the inputs for the probe signals use the same
GND connection.
6.6.2.4 Probe Signal Input
At this input the measurement signal delivered from the probe is connected.
The maximal converted input voltage range is ±2 V with gain x5 and ±0.2 V
with x50.
The supply of the probe and the input of the probe signal use the same GND
connection.
6.6.2.5 Measurement Signal Output
At this output the amplified measurement signal is available. At maximum
amplitude the maximal output current is 2 mA. Correspondingly the load has
to be at least 5 kΩ. For smaller amplitudes the output can deliver even
higher currents.
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6. Operation
cabel
wire color
probe function
connecto
r
The outcome of the given current drive capability is that higher capacitive
loads results in a reduction of bandwidth.
Unloaded the amplifier has a bandwidth of >100 kHz whereby even fast
transient signals can be transferred.
6.6.2.6 Gain Switch
With this switch the gain can be switched between x5 (±2 V → ±10 V) and
x50 (±0.2 V → ±10 V).
6.6.3 Adapter Cable
3 pieces of 1-axis adapter cable are supplied with the AS-Adapter 3. These
cables have a 15-pin SubD socket on one side and four individual wires on
the other side. Thus, with this adapter cables 3 AS-active probes can be
easily connected to the AS-adapter 3. For ease of use, the 3 adapter cables
are assigned according to the channels "X, Y, Z".
The cables can be extended both on the side of the SubD socket with probe
extension cables and on the side of the single conductors.
The assignment of the individual conductors to the respective connection of
the probe or the connection of the AS-probe adapter is shown in Table 2
below.
GE +3V +3V
X GN -3V -3V
WS probe signal IN X
BR ground IN GND
GE +3V +3V
Y GN -3V -3V
WS probe signal IN Y
BR ground IN GND
GE +3V +3V
Z GN -3V -3V
WS probe signal IN Z
BR ground IN GND
Table 2
AS-Adapter 3
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6. Operation
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6. Operation
Figure 64 Adapter cable „X, Y, Z”
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6. Operation
Attention should be paid that there is a connection between GND and
cable shield as well as the connector housing in the adapter cable. At
brass probes this is also connected to GND. Possibly an isolated
installation of the probe is necessary to prevent an unintended
connection between measuring GND and protective earth.
6.6.4 Usage of the AS-Adapter 3
There are three connections to use the AS-Adapter3.
First, the AS active probes are connected to the "± 3V" and "IN X", "IN Y",
"IN Z" terminals of the AS adapter 3 using the 3 enclosed adapter cables.
For pin assignment of the adapter cable, see table 2 on page 80.
For power supply, the input "Power" is connected to a voltage source, which
provides a DC voltage between 9 V and 36 V.
Third, the outputs "OUTX", "OUTY", "OUTX" are connected to the analog
input of a measuring transducer, such as a PLC or connected to an
oscilloscope.
The gain switch is moved to the desired position (x5 or x50).
On the following pages 83 and 84 2 different connection options are shown.
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6. Operation
Figure 65 Connection AS-Adapter 3 with 1-axis AS-active probes
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6. Operation
Figure 66 Connection AS-Adapter 3 with 3-axis AS-active probe
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7. Technical Specifications
7.1 Teslameter FM 302 (without AS-Active-Probe):
Measuring modes DC / AC(RMS)
Ranges 3 ranges per probe,
see technical specification of the AS-probes
sensitivity x1; x10; x100
Bandwidth (-3 dB) DC: DC – ≥100 kHz
AC: <5 Hz – ≥100 kHz
depends also on the used probe
Measurement uncertainty DC in x1: <0,1 % ±2 Digit (at 23 °C ±1 °C)
in x10: <0,1 % ±5 Digit (at 23 °C ±1 °C)
in x100: <0,1 % ±20 Digit (at 23 °C ±1 °C)
offset adjustable with zero-function
Adjustable offset ±4500 digit
at most sensitive range (x100)
Measurement uncertainty RMS 16.7 Hz: ≤-0.3 dB (at 23 °C ±1 °C)
50 Hz: ≤ -0.1 dB (at 23 °C ±1 °C)
with level ≥5 % of range, sine wave
Temperature coefficient max. ±0.01 %/K, typ. <±0.003 %/K
Zero drift max. ±3 digit/1K, typ. ±1 digit/1K (DC at most
sensitive range
Input resistance 10 kΩ ±0.1 %
Operation keypad with 8 keys
USB interface
Operation temperature range +5 °C to +50 °C
Storage temperature range -10 °C to +50 °C
Max. relative humidity 70 % at +35 °C
Operation in magnetic field undisturbed up to at least 350 mT
observe action of force!
Power 9 V battery
at least 400 mAh battery or accumulator,
life time > 20 h, depending on probe type,
jack for 9 V power adapter
9 V DC, 40 mA, minus at inner port
USB interface (low power device)
Dimension:
Length 166 mm (without connected plugs)
Width 88 mm (without connected plugs)
Thickness 31 mm
Weight 225 g (without 9 V battery)
271 g (with 9 V battery)
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7. Technical Specifications
LCD display:
Display 4½ digit two line LCD display
Display range ±25100 digit
Resolution
(e.g. 0.1 mT at range of 2 T)
Measuring modes mean value (DC)
true effective value (AC / true RMS)
Measuring modes absolute measurement
relative measurement
minimal measurement
maximal measurement
Display unit Tesla, Gauss, Oersted, A/m
Update rate given by measuring time
Rise time RMS meas. typ. 0.3 s
Measuring time settable 0.1 s (10 Hz) to 5 s (via keypad)
or 25.5 s (via USB interface)
Digital filter moving average filter with settable filter length
1 to 64 values
Analog output:
Output voltage ±2.7 V
Factor ±2 V per full scale of probe
(e.g. range 2 T → factor 1 V/T)
Bandwidth (-3 dB) DC: DC – ≥100 kHz
AC: <5 Hz – ≥100 kHz
depends also on the used probe
Rise time < 2 µs
Output connector BNC
Output impedance 50 Ω
USB Interface:
Connector USB-B jack
Standard USB 1.1 / USB 2.0 compatible
Driver Windows, Linux, Mac
PC interface creates a virtual serial port
Control via ASCII-commands
1
/
of each measurement range of probe
20.000
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7. Technical Specifications
Control Software at CD:
control possibilities all control possibilities accessible via the USB
interface
measured value display current measured value as number with unit
value of the set display mode as number with
unit
oscilloscope-like display
limit comparator
oscilloscope display last 100 measured values
display range given by probe and sensitivity
setting
or only 1/10 of that (10 times more sensitive)
file format as JPEG, PNG, BMP, TIFF, GIF or
EMF image
data logging single values via key press or
continuously automatic
Log format comma separated and period as decimal
separator (CSV)
semicolon separated and comma as decimal
separator
time stamp with 0.1 s resolution, measured
value, unit
Limit comparator with lower and upper limit
display if measured value below, between
or above limits
possibility to ignore polarity
display of the limits in oscilloscope
display
System requirements Windows with .NET Framework 4.0 available
(since Windows XP)
.NET Framework 4.0
(will be installed by control software)
Source code as Visual Basic 2010 Express project
Technical specifications are subject to change without prior notice!
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7. Technical Specifications
7.2 AS-Active-Probes
Transversal
Figure 67 AS-NTP 0,6 transverse probe
Figure 68 AS-NTM, AS-LTM and AS-NTM-2
transverse probe brass
Figure 69 AS-NTP-Hot-05 transverse probe
Figure 70 AS-NTP-Flex transverse probe
Figure 71 AS-NTP-Flex 0,6 transverse probe
Figure 72 AS-NCu-Wire transverse probe Wire
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7. Technical Specifications
Axial
Figure 73 AS-NAP, AS-LAP and AS-HAP axial probe
Figure 74 AS-UAP GEO-X axial probe
Figure 75 AS-UAP Lot axial probe
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7. Technical Specifications
range
transfer factor
7.2.1 Sensitivity Classes – Overview
Every AS-active-probe delivers a calibrated, analog output signal whose
level depends on the measured field. Our probes are offered in different
sensitivity classes. Table 2 shows the measuring ranges and transfer factors
in dependence of the class.
class
High:
Normal:
Low:
Ultralow:
(1) calibrated up to 12 T
The Teslameter FM 302 offers the opportunity to switch the sensitivity
between x1, x10 and x100. Thus with every probe a wide measuring range
can be covered. Furthermore the Teslameter FM 302 offers switching of the
display unit. Table 3 shows the resulting measuring ranges and Table 4 the
transfer factors for the analog output.
probe without Teslameter
(1)
20 T 200 kG 15,92 MA/m 2 V / 20 T
2 T 20 kG 1592 kA/m 2 V / 2 T
0,2 T
200 µT
2 kG 159,2 kA/m 2 V / 0,2 T
2 G 159,2 A/m 2 V / 200 µT
Table 2
probe
(1)
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7. Technical Specifications
ranges with Teslameter FM
302 (FM
205)
(1)
transfer factors with
(1)
class
High:
Normal:
Low:
Ultralow:
(1) calibrated up to 12 T
range x1, x10, x100
x1
x10
x100
x1
2000 mT
x10
x100
x1
x10
x100
x1
x10
x100
20 T
2 T
0,2 T
200 mT
20 mT
200 mT
20 mT
2 mT
200 µT
20 µT
2 µT
200 kG
20 kG
2 kG
20 kG
2 kG
0,2 kG
2000 G
200 G
20 G
2000 mG
200 mG
20 mG
Table 3
200 kOe
20 kOe
2 kOe
20 kOe
2 kOe
0,2 kOe
2000 Oe
200 Oe
20 Oe
2000 m Oe
200 m Oe
20 m Oe
15,92 MA/m
1592 kA/m
159,2 kA/m
1592 kA/m
159,2 kA/m
15,92 kA/m
159,2 kA/m
15,92 kA/m
1,592 kA/m
159,2 A/m
15,92 A/m
1,592 A/m
class
High:
Normal:
Low:
Ultralow:
(1) calibrated up to 12 T
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Teslameter FM 302 (FM 205)
range x1, x10, x100
x1
x10
x100
x1
x10
x100
x1
x10
x100
x1
x10
x100
2 V / 20 T
2 V / 2 T
2 V / 0,2 T
2 V / 2000 mT
2 V / 200 mT
2 V / 20 mT
2 V / 200 mT
2 V / 20 mT
2 V / 2 mT
2 V / 200 µT
2 V / 20 µT
2 V / 2 µT
Table 4
7. Technical Specifications
ranges and transfer factors
(1)
To ease the connection of the AS-active-probe to existing analog inputs with
±10 V input range, the AS-probe adapter contains an integrated amplifier.
This amplifies the output signal of the AS-active-probes from ±2 V to ±10 V.
With a switch, an additionally 10times higher gain can be chosen which
allows to perform even sensitive measurements.
Table 5 shows the measurement ranges as well as the transfer factors for
the analog output resulting from the different probes.
class
High:
Normal:
Low:
Ultralow:
with AS-probe adapter
range x5, x50
x5
x50
x5
x50
x5
x50
x5
x50
(1) calibrated up to 12 T
Units
• T – Tesla
• G – Gauss
• Oe – Oersted
• A/m - Ampere per Meter
For conversion of magnetic units see our application note “PE005 –
Magnetische Maßeinheiten und deren Umrechnung”.
20 T
2 T
2000 mT
200 mT
200 mT
20 mT
200 µT
20 µT
10 V / 20 T
10 V / 2 T
10 V / 2000 mT
10 V / 200 mT
10 V / 200 mT
10 V / 20 mT
10 V / 200 µT
10 V / 20 µT
Table 5
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7. Technical Specifications
thick
operation
7.2.2 AS-active-probes – Overview Normal
For most application our AS-active-probe of class normal are suited. The
fields typically occurring in technical areas can be measured with this
probes.
class model type linearity error
AS-NTP 0,6 T < 0.5 % ±0.2 mT 0.6 ± 0.1
AS-NTM T-Ms < 0.2 % ±0.2 mT 1.4 ± 0.1
AS-NTM-2 T-Ms
AS-NAP A < 0.5 % ±0.2 mT Ø 6.0
Normal:
AS-NTP-Hot-05 T < 0.2 % ±0.2 mT 1.5 ± 0.1
AS-NTP-Flex T
AS-NTP-Flex
0,6
AS-NCu-Wire T
(2) at +20 °C or +25 °C
(3) probe, handle and cable = -40 °C to +150 °C;
probe plug = +5 °C to +50 °C
(4) at first 70 mm = +5 °C to +100 °C;
handle, cable and probe plug = +5 °C to +50 °C
(5) at first 150 mm = +5 °C to +100 °C;
handle, cable and probe plug = +5 °C to +50 °C
(7) at first 70 mm = +5 °C to +150 °C;
handle, cable and probe plug = +5 °C to +50 °C
< 0.05% ±0.2 mT
< 0.5 % ±0.2 mT
T < 0.5 % ±0.2 mT 0.6 ± 0.1
< 0.5 % ±0,2 mT
Table 6
(2)
up to 1.5 T
up to 1.5 T
mm
1.4 ± 0.1
0.6 ± 0.1
0.6 ± 0.1
temp. °C
5 – 100
5 – 50
5 – 50
5 – 50
-40 – 150
5 – 100
5 – 150
5 – 100
(4)
(3)
(4)
(4)
(5)
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7. Technical Specifications
thick
operation
thick
operation
High:
7.2.3 AS-active-probes – Overview Earth Magnetic Field
For the measurement of very small fields like e.g. the earth magnetic field
we offer our probes of class Ultralow. With the possibility of compensation of
±70 µT the overlaying earth magnetic field can be masked. So even very
small stray and noise fields can be measured with this probes.
class model type linearity error
AS-UAP Geo-X A < 0.8 % ±0.2 µT
Ultralow:
AS-UAP Lot A < 0.8 % ±0.2 µT Ø 18.8
Table 7
(2) at +20 °C or +25 °C
7.2.4 AS-active-probes – Overview High Field
Especially for the measurement of very high field the probe AS-HAP of class
High has been developed. Such high permanent fields are normally only
achieved with superconductors. Temporary they can be generated with
other setups, too.
class model type linearity error
AS-HAP A < 2.0 % ±20 mT
Table 8
(2) at +20 °C or +25 °C
(2)
mm
(2)
mm
Ø 17
Ø 6.4
temp. °C
5 – 50
5 – 50
temp. °C
5 – 50
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7. Technical Specifications
thick
operation
7.2.5 AS-active-probes – Overview Low Field
If only small fields shall be measured, also the probes of class Low can be
used. Typically they are used to measure residual magnetism at produced
parts or to control compliance with limit values (e.g. employee safety,
pacemaker).
class model type linearity error
AS-LTM T-Ms < 0.2 % ±0.1 mT 1.4 ± 0.1
Low:
(2) at +20 °C or +25 °C
AS-LAP A < 0.5 % ±0.1 mT Ø 6.0
Table 9
(2)
mm
temp. °C
5 – 50
5 – 50
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7. Technical Specifications
temperature
7.2.6 AS-active-probes – Overview Further Data
class model
High:
AS-HAP DC – 35 kHz 0.2 mm² -0.05 %/K
AS-NTP 0,6 DC – 35 kHz 0.2 mm² -0.03 %/K
AS-NTM DC – 25 kHz 0.2 mm² -0.03 %/K
AS-NTM-2 DC – 25 kHz 0.12 mm²
AS-NAP DC – 35 kHz 0.2 mm² -0.03 %/K
Normal:
AS-NTP-Hot-05 DC – 35 kHz 0.5 mm² ±1.0% ±0.2 mT
AS-NTP-Flex DC – 0.5 kHz 2 mm² -0.03 %/K
AS-NTP-Flex
0,6
AS-NCu-Wire DC – 35 kHz 2 mm² -0.03 %/K
AS-LTM DC – 10 kHz 0.2 mm² -0.03 %/K
Low:
AS-LAP DC – 10 kHz 0.2 mm² -0.03 %/K
AS-UAP Geo-X DC – 0.5 kHz
Ultralow:
AS-UAP Lot DC – 0.5 kHz
(6) in range of –10 °C to +150 °C
bandwidth
(-3 dB)
active area
DC – 35 kHz 0.2 mm² -0.03 %/K
Table 10
Ø 5 mm
x 22 mm
Ø 5 mm
x 22 mm
coefficient or.
error
±0,005 %/K
±0.1 %/K
±0.1 %/K
(6)
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7. Technical Specifications
7.2.7 Axial Probe 12 T (AS-HAP)
Figure 76 Size axial probe 12 T (AS-HAP)
Ranges (with FM 302) ±0.2 T; ±2 T; ±20 T (calibrated up to ±12 T)
Effective area 0.2 mm²
Diameter of support Ø 6.4 mm
Length of support 180 mm
Transfer factor 0.1 V/T
Bandwidth (-3 dB) 0 – 35 kHz
Rise time <3 µs
Linearity error <2,0 % ±20 mT (at 20 °C)
Temperature coefficient max. -0.1 %/K, typ. -0.05 %/K (0 to 50 °C)
Zero drift max. ±0.05 mT/K, typ. 0.03 mT/K (DC)
Noise typ. 173 µT
typ. 43 µTPP (DC – 10 Hz, 50 s)
Operation temperature +5 °C to +50 °C
Storage temperature -10 °C to +60 °C
Max. relative humidity 70 % at +35 °C
Power ±3 V through FM 302, AS-probe adapter,
AS-Adapter 3 or PLC
Connector 15 pol. SubD
Output impedance <1 Ω
Length of cable 2.95 m
Technical specifications are subject to change without prior notice!
(10 Hz – 10 kHz)
RMS
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7. Technical Specifications
7.2.8 Transverse Probe 2000 mT (AS-NTP 0,6)
Figure 77 Size transverse probe 2000 mT (AS-NTP 0,6)
Ranges (with FM 302) ±20 mT; ±200 mT; ±2000 mT
Effective area 0.2 mm²
Thickness of support 0.6 ±0.1 mm
Length of support 70 mm
Width of support 5 ±0.5 mm
Transfer factor 1 V/T
Bandwidth (- 3 dB) 0 - 35 kHz
Rise time <3 µs
Linearity error <0.5 % ±0.2 mT (at 20 °C ±1 °C)
Temperature coefficient max. -0.05 %/K, typ. -0.03 %/K (0 to 50 °C)
Zero drift max. ±0.020 mT/K, typ. ±0.010 mT/K (DC)
Noise typ. 21 µT
typ. 18 µTPP (DC – 10 Hz, 50 s)
Operation temperature +5 °C to +100 °C (only at first 70 mm)
+5 °C to +50 °C (grip, cable, probe connector)
Storage temperature -10 °C to +60 °C
Max. relative humidity 70 % at +35 °C
Power ±3 V through FM 302, AS-probe adapter,
AS-Adapter 3 or PLC
Connector 15 pol. SubD
Output impedance <1 Ω
Length of cable 1.5 m
Technical specifications are subject to change without prior notice!
(10 Hz – 10 kHz)
RMS
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7. Technical Specifications
7.2.9 Transverse Probe Brass 2000 mT (AS-NTM)
Figure 78 Size transverse probe brass 2000 mT (AS-NTM)
Ranges (with FM 302) ±20 mT; ±200 mT; ±2000 mT
Effective area 0.2 mm²
Thickness of support 1.4 ±0.1 mm
Length of support 70 mm
Width of support 5 ±0.1 mm
Transfer factor 1 V/T
Bandwidth (-3 dB) 0 - 25 kHz
Rise time <6 µs
Linearity error <0.2 % ±0.2 mT (at 20 °C ±1 °C)
Temperature coefficient max. -0.05 %/K, typ. -0.03 %/K (0 to 50 °C)
Zero drift max. ±0.020 mT/K, typ. ±0.010 mT/K (DC)
Noise typ. 21 µT
typ. 18 µTPP (DC – 10 Hz, 50 s)
Operation temperature +5 °C to +50 °C
Storage temperature -10 °C to +60 °C
Max. relative humidity 70 % at +35 °C
Power ±3 V through FM 302, AS-probe adapter,
AS-Adapter 3 or PLC
Connector 15 pol. SubD
Output impedance <1 Ω
Length of cable 1.5 m
Technical specifications are subject to change without prior notice!
(10 Hz – 10 kHz)
RMS
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7. Technical Specifications
7.2.10 Transverse Probe Brass with Very High Precision 2000 mT (ASNTM-2)
Figure 79 Size transverse probe brass 2000 mT (AS-NTM-2)
Ranges (with FM 302) ±20 mT; ±200 mT; ±2000 mT
Effective area 0.12 mm²
Thickness of support 1.4 ±0.1 mm
Length of support 70 mm
Width of support 5 ±0.1 mm
Transfer factor 1 V/T
Bandwidth (- 3 dB) 0 – 25 kHz
Rise time <6 µs
Linearity error <0.05 % ±0.2 mT (DC, at 20 °C ±1 °C)
Temperature coefficient max. ±0.005 %/K (5 °C to 50 °C)
Zero drift max. ±0.005 mT/K, typ. ±0.003 mT/K
Noise typ. 21 µT
typ. 12 µTPP (DC – 10 Hz, 50 s)
Operation temperature +5 °C to +50 °C
Storage temperature -10 °C to +60 °C
Max. relative humidity 70 % at +35 °C
Power ±3 V through FM 302, AS-probe adapter,
AS-Adapter 3 or PLC
Connector 15 pol. SubD
Output impedance <1 Ω
Length of cable 1.5 m
Technical specifications are subject to change without prior notice!
(10 Hz – 10 kHz)
RMS
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