Metrol THM1176 User manual

Magnetic precision has a name
Three-axis Magnetometers
THM1176 and TFM1186
User's Manual
Version 2.0
(Revision 1.0)
February 2020

THM1176/TFM1186 User’s Manual v 2.0 r 1.0 –02/20 Copyright © 2020 Metrolab Technology SA
www.metrolab.com
ii
REVISION HISTORY
v. 1.0 r. 1.0
May 2008
First release
v. 1.0 r. 1.1
May 2008
Various fixes
v. 1.1 r. 1.0
July 2008
Various fixes
v. 1.2 r. 1.0
December 2009
Updates for version 3.x of software
Updates for version 2.x of firmware
Updates for THM1176-LF
Various fixes
v. 1.2 r. 1.1
February 2010
Add notice concerning WEEE Directive
v. 1.2 r. 1.2
July 2010
Restore formatting of -HF dimensions
v. 1.3 r. 1.0
January 2012
Update for software release 4.0 and firmware
release 3.0
Update links for external documentation
Add documentation for THM1176-HFC
v. 1.3 r. 1.1
April 2012
Correct installation procedure
v. 1.3 r. 1.2
April 2014
Add documentation for THM1176-MF, TFM1186
Adapt documentation for SoMo™ 655
Remove references to electronic newsletter
Update links to USB documentation
Update for LabVIEW Mobile Module end-of-life
Miscellaneous clean-ups
v. 1.3 r. 1.3
November 2014
Update for different versions of THM1176-MF and
THM1176-HFC sensor
Correct section numbering in Chapter 5
v. 1.3 r. 1.4
October 2016
Update for different versions of THM1176-MF
sensor
Update links for USB references
v. 2.0 r. 1.0
February 2020
Rewrite Chapter 2, “Quick Start Guide”
Rewrite Chapter 3, “Overview”
Delete Chapter 4, “Software User Interface”
Rewrite Chapter 5, “Application Programming”
Update dimensions of THM1176-HFC

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CONTENTS
1- Introduction.......................................................................................................1
2- Quick Start Guide..............................................................................................3
2-1 Kit Contents ............................................................................................................................................ 3
2-2 Windows Software Installation and Removal..........................................................................................3
2-2-1 Software Installation.....................................................................................................................3
2-2-2 Software Removal........................................................................................................................4
2-3 Macintosh Software Installation and Removal.........................................................................................4
2-3-1 Software Installation.....................................................................................................................4
2-3-2 Software Removal........................................................................................................................4
2-4 Starting to Measure.................................................................................................................................5
2-5 Using the Handheld Kit ...........................................................................................................................5
2-6 Precautions.............................................................................................................................................6
2-7 Axis Orientations.....................................................................................................................................8
3- Overview............................................................................................................9
3-1 Hardware Block Diagram........................................................................................................................ 9
3-2 Sensors...................................................................................................................................................9
3-3 Measurement Process ..........................................................................................................................10
3-4 Characteristics and Benefits ................................................................................................................. 11
3-5 Probe Mechanical Design ..................................................................................................................... 13
3-6 Host Computer Interface.......................................................................................................................14
3-7 Host Computer and Software................................................................................................................15
3-8 Calibration, Maintenance, Repair and Warrenty....................................................................................15
4- Options for Computer Control.......................................................................17
4-1 EZMag3D Turn-key Software................................................................................................................17
4-2 EZMag3D Plugins................................................................................................................................. 17
4-3 THM1176 Instrument Control API......................................................................................................... 17
4-4 THM1176 Instrument Manager ............................................................................................................. 18
5- USB Interface ..................................................................................................19
5-1 General.................................................................................................................................................19
5-2 SCPI Instrument Model.........................................................................................................................20
5-3 IEEE 488.2 / SCPI status registers ....................................................................................................... 22
5-4 USBTMC-USB488 Controls.................................................................................................................. 26
5-5 IEEE 488.2 Common Commands.........................................................................................................27
5-6 SCPI Commands ..................................................................................................................................27
5-7 Programming Hints ...............................................................................................................................40
6- Technical Specifications................................................................................43
6-1 Measurement........................................................................................................................................ 43
6-2 Interface................................................................................................................................................44
6-3 Operating conditions............................................................................................................................. 44
6-4 Mechanical –THM1176-MF/HF............................................................................................................45

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6-5 Mechanical –THM1176-HFC................................................................................................................ 47
6-6 Mechanical –THM1176-LF................................................................................................................... 48
6-7 Mechanical –TFM1186......................................................................................................................... 48
6-8 Software................................................................................................................................................49
6-9 Warranty, Calibration, Certification and Maintenance........................................................................... 49
7- THM1176-MF/HF/HFC Sensor Details............................................................50
8- Error Codes.....................................................................................................52
8-1 0: No Error ............................................................................................................................................52
8-2 -100: Command Errors..........................................................................................................................52
8-2-1 -102: Syntax error...................................................................................................................... 52
8-2-2 -104: Data type error..................................................................................................................52
8-2-3 -115: Unexpected number of parameters ..................................................................................52
8-2-4 -123: Exponent too large............................................................................................................ 52
8-2-5 -151: Invalid string data..............................................................................................................52
8-2-6 -171: Invalid expression.............................................................................................................53
8-3 -200: Execution Errors ..........................................................................................................................53
8-3-1 -221: Settings conflict.................................................................................................................53
8-3-2 -222: Data out of range..............................................................................................................53
8-3-3 -225: Out of memory.................................................................................................................. 54
8-4 -400: Query Errors ................................................................................................................................54
8-4-1 -400: Query error .......................................................................................................................54
8-4-2 -410: Query INTERRUPTED ..................................................................................................... 54
8-4-3 -420: Query UNTERMINATED .................................................................................................. 54
8-4-4 -440: Query UNTERMINATED after indefinite response ........................................................... 54
8-5 100: Instrument-Dependent Command Errors ......................................................................................54
8-5-1 101: Invalid value in list..............................................................................................................54
8-5-2 103: Wrong units for parameter .................................................................................................54
8-6 200: Instrument-Dependent Execution Errors.......................................................................................54
8-6-1 200: Software Error....................................................................................................................54
8-6-2 204: Data buffer was overrun..................................................................................................... 55
8-6-3 205: Measurements were over-range........................................................................................55
8-6-4 206: Timer was overrun .............................................................................................................55
8-6-5 207: Bad data compression....................................................................................................... 55

THM1176/TFM1186 User’s Manual v 2.0 r 1.0 –02/20 Copyright © 2020 Metrolab Technology SA
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1
GETTING STARTED
1-
Introduction
Metrolab’s Three-axis Magnetometers are used to measure magnetic field
strength. Simultaneous measurement of all three components of the magnetic
field provides the total field no matter the orientation of the probe, which greatly
facilitates many measurement tasks such as field mapping. The extraordinarily
compact design, along with the optional ruggedized tablet, makes for a powerful,
autonomous and portable magnetometer, excellent for field use.
This manual covers the entire THM1176 family, including the following models:
A. THM1176-MF (“Three-axis Hall Magnetometer –Medium Field”),
B. THM1176-HF (“Three-axis Hall Magnetometer –High Field”),
C. THM1176-HFC (“Three-axis Hall Magnetometer –High Field Compact”),
D. THM1176-LF (“Three-axis Hall Magnetometer –Low Field”), and
E. TFM1186 (“Three-axis Fluxgate Magnetometer”).
For an overview of the capabilities of each of these instruments, please see
Chapter 3-Overview, Chapter 6-Technical Specifications and Chapter 7-
THM1176-MF/HF/HFC Sensor .
A
B
C
D
E

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The THM1176 family of instruments resembles other standard USB devices; it
and its software are easy to install and easy to use. Nonetheless, please take a
moment to browse through Chapter 2-Quick Start Guide and Chapter 3-Overview.
Pay particular attention to the cautionary notes.
It is easy to develop custom software for the THM1176 family; please see Chapter
4-Options for Computer Control, Chapter 5-USB Interface, and Chapter 8-Error
Codes.
Finally, keep your instrument accurate and up to date by having it recalibrated at
regular intervals. The recommended calibration interval is 18 months. You can
benefit from a discounted price for the calibration if you return your instrument to
Metrolab at a time that corresponds to our batch calibrations; please see Section
6-9 for details.
You can also download the latest firmware, software and manual, free of charge.
We post all updates on our website. Section 3-7 provides some additional details.
We hope that your Three-axis Magnetometer will help you perform your magnetic
field measurements easily and accurately. If you have problems and your reseller
cannot help you further, the Metrolab team is ready to help. Even if you don’t have
problems, we are always interested in knowing more about how our instruments

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GETTING STARTED
2-
Quick Start Guide
2-1 KIT CONTENTS
Your shipment should contain:
•A THM1176 or TFM1186
magnetometer. If you ordered a
“Duo Kit”, you will receive two
probes.
•A calibration certificate.
•A zero-gauss chamber, for
measuring and adjusting the probe’s
zero offset. The TFM1186 does not come with a zero-gauss chamber –see
the note in Section 2-6, Precautions.
•A USB thumb drive with the software and documentation.
•A carrying case.
•Optionally, if you ordered the Handheld Kit, a ruggedized Windows tablet.
In addition to the tablet itself, you should receive:
oa Mini-USB to USB-A adapter cable;
oa pistol grip with an extension battery; and
oa charger with adapter plugs for Europe/Switzerland, U.K., U.S. and
Australia.
2-2 WINDOWS SOFTWARE INSTALLATION AND REMOVAL
2-2-1 Software Installation
The order in which you perform the following steps is not important:
•Run the EZMag3D installer, Metrolab-EZMag3D-InstallerWindows.exe,
following the on-screen instructions.
•Run the installer for the libusbK device driver, InstallDriver.exe, following
the on-screen instructions.

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When the installation is complete, you will find a program link “EZMag3D
<version>”on your desktop. You will find the same program link in the folder
Metrolab of the Start Menu, alongside a link “EZMag3D <version> Manual”to the
online help. As usual, you can also access these items via a search.
2-2-2 Software Removal
•In the Explorer, delete the EZMag3D parameter folder shown in the
Settings screen. By default, it is in your AppData folder.
•Open the Apps & Features settings panel.
•Uninstall Metrolab EZMag3D.
•Uninstall UsbK Development Kit.
2-3 MACINTOSH SOFTWARE INSTALLATION AND REMOVAL
2-3-1 Software Installation
•Run the EZMag3D installer, Metrolab-EZMag3D-InstallerMacOs, following
the on-screen instructions.
Note that the default installation location is in your personal Applications folder,
not the system-wide Applications folder.
When the installation is complete, you will find the program EZMag3D in the folder
you specified during installation. In the same folder, you will also find a link
“EZMag3D Manual”to the online help. As usual, you can launch EZMag3D by
double-clicking its icon; you can also create an alias on the Dock or Desktop, or
you can launch it from a Spotlight search.
2-3-2 Software Removal
•In the Finder, delete the EZMag3D parameter folder shown in the Settings
screen. By default, this is ~/Library/Application Support/EZMag3D; since
your Library folder is usually hidden, you have to select the Finder's Go >
Go to Folder... menu item, and then enter ~/Library/Application
Support/EZMag3D.
•Open the program folder that you specified during installation
(~/Applications/EZMag3D <version> by default) and run the program
EZMag3D Uninstaller.

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2-4 STARTING TO MEASURE
•Start the EZMag3D software.
The first time you run EZMag3D, it will open the Connection Screen.
•Plug in the THM1176 or TFM1186.
The magnetometer will take approximately 10 seconds to boot and should
then appear on the Connection Screen, allowing you to connect to the
instrument.
•Place the probe in the magnet. On the THM1176-MF and THM1176-HF,
you can remove the probe cap to access narrow gaps –see Chapter 3-
Overview. See the EZMag3D Manual for details on using the software.
•(Does not apply to TFM1186 –see Section 2-6!) Check the offset before
each series of measurements by placing the probe in the Zero Gauss
Chamber. If the offset is higher than desired, leave the probe in the Zero
Gauss Chamber and perform the User Offset Correction procedure.
2-5 USING THE HANDHELD KIT
The ruggedized Windows tablet included in the Handheld Kit is like any other
Windows computer; all the procedures in the previous sections apply. Here are
some additional hints:
•Use the adapter included to plug the THM1176/TFM1186 into the tablet’s
Mini-USB connector.
•The Mini-USB connector is also used to recharge the tablet, so the tablet
cannot be recharged while measuring. However, a fully charged tablet
should provide roughly four hours of operation, making for a compact and
lightweight handheld solution.
•The hand strap on the back of the tablet is very practical, but it is
unfortunately made for using the tablet in portrait mode, which is not the
optimal orientation for EZMag3D.
•The pistol grip, on the other hand, places the tablet in landscape mode,
and also dramatically extends the battery life, to more than a day. In fact,
by plugging the power supply into the pistol grip rather than the tablet itself,
you can recharge while measuring. However, note the precautions below.

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2-6 PRECAUTIONS
CAUTION
High magnetic field gradients –as found, for example, around an MRI or NMR
spectroscopy magnet –will subject the USB connector and the tablet to strong
forces. To prevent injury from flying objects or whiplashing cables, be sure to
hold these components securely when you are around a strong magnet.
NOTICE
Do not bend the probe cable sharply. This is a special cable with individually
shielded signal wires, in order to minimize induction artifacts. Sharp bends
break the shielding.
This product conforms to the WEEE Directive of the European
Union (2002/96/EC) and belongs to Category 9 (Monitoring and
Control Instruments). For proper environment friendly disposal,
you can return the instrument free of charge to us or our local
distributor.
SPECIAL NOTICE FOR THE TABLET
When the tablet’s battery level drops below 10%, the THM1176/TFM1186 will
no longer function (BIOS > v. 1.11). This is because the tablet’s USB port,
acting as a USB host, supplies power to the instrument, and must switch back
to USB device mode in order to be able to charge the tablet. This should
happen before the battery is completely depleted to avoid the USB port being
permanently stuck in host mode.
To use the pistol grip for additional battery power, press the button on the back
of the pistol grip for 1 second, to enable its power output. You should see the
tablet’s power LED turn red, and the Windows “charging battery” icon. Press
the button on the pistol grip for 3 seconds to disable its power output.
!

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SPECIAL NOTICE FOR THE THM1176-HF and THM1176-HFC
Remember that the THM1176-HF is only calibrated to 14.1 T (formerly 3 T),
and the THM1176-HFC only to 1.5 T. Consequently, the 20 T range on these
instruments is only calibrated up to these limits. You should try to use the
lower ranges whenever possible; the best is to leave the instrument in auto-
ranging mode (the default).
SPECIAL NOTICE FOR THE THM1176-HFC
The probe is fragile. Be very careful when handling; even the weight of the
instrument cable is sufficient to damage the probe. Damage to either the
sensor package or signal cable will destroy the sensor. We strongly suggest
storing the probe in its protective case when not in use.
The sensor is sensitive to Electrostatic Discharge (ESD). Be sure to ground
yourself and follow proper procedure when handling the sensor.
SPECIAL NOTICE FOR THE TFM1186
Do not use the zero-offset correction feature with the TFM1186. In fact, the
fluxgate sensor is so sensitive that most zero-gauss chambers are completely
inadequate, and the zero-offset procedure will introduce a large offset error. If
the zero-offset procedure is nonetheless executed, you can restore the factory
offset as described in the EZMag3D manual.

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2-7 AXIS ORIENTATIONS
The orientation of the axes relative to a THM1176 probe is as follows:
Relative to the THM1176-MF and -HF sensors:
Similarly for the THM1176-HFC sensor:
For the TFM1186, the axis orientations are printed on the sensor.
X
Z
Y
Z

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USING THE THM1176/TFM1186
3-
Overview
This chapter provides a short technical overview of the THM1176 family of
instruments and what you can do with them.
3-1 HARDWARE BLOCK DIAGRAM
Figure 1. THM1176/TFM1186 functional block diagram
3-2 SENSORS
The sensors used in the different models are as follows:
•THM1176-MF, “Three-axis Hall Magnetometer, Medium Field”:
Single-chip 3-axis Hall sensor with ranges of 0.1, 0.3, 1 and 3 T.
•THM1176-HF, “Three-axis Hall Magnetometer, High Field”:
Single-chip 3-axis Hall sensor with ranges of 0.1, 0.5, 3 and 20 T.
•THM1176-HFC, “Three-axis Hall Magnetometer, High Field Compact”:
Single-chip 3-axis Hall sensor with ranges of 0.1, 0.5, 3 and 20 T, in a
compact package.
•THM1176-LF, “Three-axis Hall Magnetometer, Low Field”:
Assembly of 3 single-axis Hall sensors, with on-chip flux concentrators,
with a range of 8 mT.
•TFM1186, “Three-axis Fluxgate Magnetometer”:
3-axis fluxgate sensor, with a range of 100 µT (200 µT upon special order).
This sensor distinguishes itself from the others in a number of respects:
differential output, requiring an input adapter; no integrated temperature
sensor; and a connector.

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More details on the single-chip 3-axis Hall sensors can be found in Chapter 7-
THM1176-MF/HF/HFC Sensor Details.
3-3 MEASUREMENT PROCESS
•The analog sensors measure the three vector components of the magnetic
field and the sensor’s internal temperature.
•At the input of the electronics, the inputs from the sensor pass through a 1
kHz anti-aliasing filter. This 2nd-order filter is designed to be flat to 1 kHz;
the -3 dB point is at several kHz.
•A multiplexer selects each of the inputs in turn and routes the signal to a
16-bit ADC.
•A microprocessor (µP) receives commands from the host computer,
controls the measurement process, and returns the data to the host.
•To reduce noise, the µP samples each field component several times,
depending on the degree of averaging (oversampling) specified by the
user. The sample rate is as fast as possible –in practice just under 10 kHz.
•With this oversampling, the signals are sampled in the following order:
Bx, Bx, Bx, …, By, By, By, …, Bz, Bz, Bz, …, T
where T is temperature.
•The averaged field measurement [<Bx>, <By>, <Bz>] is then stored in the
acquisition buffer, as one measurement point. T is averaged with the
temperature measurements for the other points in the acquisition buffer.
•The µP then waits for a trigger before starting the next acquisition. The
trigger can occur immediately, at the expiration of a timer, or at the
reception of a USB trigger command, as specified by the user.
•The µP accumulates measurement points in the acquisition buffer, up to
the number specified by the user –the so-called “block size”. The
maximum block size supported by the µP is 4096 measurement points. The
acquisition is actually double buffered, to allow the acquisition to continue
while data is transferred to the host computer.
•At the end of each block of measurement points, the µP records a 64-bit
time stamp, accurate to 167 ns. It is up to the software to reconstruct a full

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time stamp for each measurement point, based on the trigger mode and
the host computer’s date/time information.
•Before sending the data to the host, each measurement point is corrected
for the sensor’s offset, gain, non-linearity, and temperature drift. The
correction factors come from a factory-supplied calibration table stored in
the µP’s nonvolatile memory. The factory parameters for offset, however,
are overridden by an updated value obtained through the zero-offset
calibration procedure, performed by the user with the sensor in the zero-
gauss chamber. The average temperature for the block is used to
compensate for temperature drift. If the user wants the raw measurements,
he can disable these corrections.
•The calibration table also contains data concerning the orthogonality of the
sensor’s axis; however, this correction is applied not by the µP, but by the
software.
3-4 CHARACTERISTICS AND BENEFITS
•Three axes:
Simultaneous measurement of all three axes of the magnetic field provides
the total field, no matter the orientation of the probe.
•Field sensitive volume:
On the THM1176-MF, -HF and -HFC, a microscopic Hall sensor volume
provides localization to a fraction of a mm, and a self-consistent
measurement of the three axes even in highly inhomogeneous fields. The
active field volume of the THM1176-LF and TFM1186 is much larger, on
the order of several mm, but this is usually sufficient for weak fields.
•Range, accuracy and resolution:
Consult these key specifications and choose the probe most appropriate
for your application:
oTHM1176-MF: most permanent- and electro-magnet applications,
including superconducting magnets up to 3 T;
oTHM1176-HF: high-field superconducting magnets to 14 T;
oTHM1176-HFC: similar, but for sub-millimeter gaps;

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oTHM1176-LF: millitesla fringe fields;
oTFM1186: nanotesla-range perturbations in, for example, the earth’s
field.
•Bandwidth of DC to 1 kHz:
The 1 kHz bandwidth allows measuring AC fields generated, for example,
by transformers and motors.
•Trigger modes:
Three trigger modes allow the acquisition procedure to be fine-tuned for the
measurement.
oImmediate trigger mode:
Immediate trigger mode –the default –starts an acquisition
sequence immediately upon receiving the measurement command.
oTimed trigger mode:
Timed trigger mode is suitable for measuring rapidly varying fields.
The maximum sample rate –writing data into the acquisition buffer –
is approximately 5.3 kSa/s, where one sample is a triplet (Bx, By,
Bz). With a simultaneous readout via USB, the maximum sample
rate is approximately 2.3 kSa/s.
oBus triggered mode:
The USB bus trigger command can be used to synchronize the
acquisition with external events. The instrument allows up to about
400 bus triggers per second.
•Measurement blocks:
The THM1176/TFM1186 contains a local memory capable of holding 4096
samples, allowing data to be acquired more quickly than it can be read out
by the USB interface.
•Averaging:
Averaging, or oversampling, can reduce measurement noise. The degree
of averaging is controllable, since long integration periods might be
beneficial for static fields, but counterproductive for time-varying fields.

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•Zero-offset calibration (not for TFM1186 –see Section 2-6!):
To guarantee the specified accuracy, the measurement offset should be
checked before each measurement sequence, using the zero-gauss
chamber supplied. If needed, the offset correction procedure will measure
and correct this offset. The correction value is written to flash memory so
that the same correction will be applied the next time the instrument is
powered up.
•Readout options:
The three field components are always acquired, but the readout can be
limited to any selected components. The readout can include a single
measurement or an entire array of measurements, and can be formatted as
an ASCII message or as a binary block. Binary data may be compressed
by a factor of two or four, for example to help reduce the traffic on a busy
USB hub. Depending on the model, the field values can be returned in
Tesla, mTesla, µTesla, nTesla, Gauss, kGauss, mGauss, equivalent proton
NMR frequency, or raw ADC values. The timestamp (in ns) and sensor
temperature (arbitrary units, not calibrated) can also be read out.
3-5 PROBE MECHANICAL DESIGN
•Protection for the sensor:
Magnetic sensors are sensitive electronic components. The plastic cover of
the THM1176-MF, -HF and -LF protects their Hall sensors from the bumps
and scrapes of normal use. For the THM1176-MF and -HF, the sensor
packaging provides effective protection even with the cap removed (see
below). However, the THM1176-HFC lacks all such protection; please note
the special handling precautions in Section 2-6, Precautions. The TFM1186
sensor is relatively large and mechanically very robust.
•Small gaps:
The THM1176-MF, -HF and -LF probes are 10 mm thick. To measure in a
smaller gap, the THM1176-MF or -HF probe cap can be removed, reducing
the thickness to 4.1 mm. If needed, the THM1176-MF or -HF sensor –only
2.3 mm thick –can be separated from the probe plastic; note, however,
that the sensor wires are delicate and can easily be broken. For even
smaller gaps, use a THM1176-HFC, whose probe is only 0.5 mm thick.

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•Stationary installation (THM1176-MF and -HF only):
Removing the cap also reveals a mounting point that allows the probe to be
permanently mounted or attached to a scanning arm. The exact position of
the field-sensitive point can be determined by optical sighting.
3-6 HOST COMPUTER INTERFACE
•USB interface:
Compliance with the USB 2.0 mechanical, electrical and protocol standard
provides basic connectivity with any USB-capable computer. The
instrument supports USB full-speed communication (12 Mbps).
•Standardized USB class driver:
Compliance with the USB Test & Measurement Class (USBTMC) allows
the instrument to be connected without installing a custom USB driver. All
that is required is a generic class driver for test and measurement
equipment, as provided by suppliers of instrumentation software.
•Standardized IEEE488.2 protocol:
Compliance with the USB488 protocol specification for USBTMC provides
all the capabilities of an IEEE488 instrument on the USB bus. IEEE488,
derived from HPIB/GPIB, is the world’s most widely used instrumentation
protocol. IEEE488 compliance allows any VISA library (Virtual Instrument
Software Architecture) to control every aspect of the instrument.
•Standardized instrument command protocol:
The SCPI standard (Standard Commands for Programmable Instruments)
is the standard developed and used by large instrumentation
manufacturers such as Tektronix and HP/Agilent/Keysight, and provides a
programming interface familiar to many instrumentation system
programmers.

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3-7 HOST COMPUTER AND SOFTWARE
The THM1176 family of magnetometers requires a host computer for power and
control. With the Handheld Kit, this host computer is a ruggedized Windows tablet;
otherwise, it is your computer. The probes supplied with the Desktop and
Handheld Kits are identical; in other words, you can also plug a probe from a
Handheld Kit into your computer.
The THM1176/TFM1186 are supplied with software, called EZMag3D. See the
included electronic manual for how to use this software. You can also integrate
this software into a larger measurement system, or even write software from
scratch; please see Chapter 4-Options for Computer Control for your different
options.
3-8 CALIBRATION, MAINTENANCE, REPAIR AND WARRENTY
•Calibration procedure:
The THM1176 family of instruments can only be calibrated by Metrolab.
This is because special magnets, tooling and software are required to
calibrate all three axes, at multiple fields and temperatures, and write the
results to flash memory.
•Recommended calibration interval:
You are of course free to fix the interval at which you send your instrument
back for calibration, within the context of your quality assurance policy.
Metrolab’s recommendation is to send the instrument back for calibration at
least once every eighteen months.
•Recommended calibration dates:
To minimize costs, Metrolab establishes a limited number of dates in the
year when batches of THM1176 family magnetometers will be calibrated.
To avoid substantial extra charges, you should ship the unit back to
Metrolab in order to coincide with one of these dates. Please see Section
6-9 for a list of these dates.
•Upgrades:
Via its website, Metrolab makes available improvements and bug fixes for
the THM1176 firmware, software and manual. The Download page of the

THM1176/TFM1186 User’s Manual v 2.0 r 1.0 –02/20 Copyright © 2020 Metrolab Technology SA
www.metrolab.com
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Metrolab website (https://www.metrolab.com/downloads/) will always
contain the latest versions.
•Firmware upgrades:
The THM1176 family of instruments is designed such that you can upgrade
the firmware yourself. Firmware upgrades are a delicate procedure, as a
failure may render the instrument unusable. Metrolab has made every
effort to make the process foolproof, but please take your time and follow
the instructions provided with the upgrade carefully.
•Repairs:
Due to the highly integrated construction of the THM1176 family, Metrolab
cannot replace individual electronic components. If you send an instrument
back for repair, we will send you a replacement unit at a standardized
exchange price –please contact Metrolab for a quotation. The replacement
unit may contain parts recovered from units previously sent in for repair;
however, it will of course be fully tested, calibrated and guaranteed.
•Warranty:
The standard warranty period is two years from the date of purchase.
During this period, Metrolab will replace a failing unit free of charge, unless
it is clear that the unit has been abused (crushed probe or electronics, torn
cable, etc.). We do not assume responsibility for consequential damage, for
example to your PC.
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