1. Hall Probe Calibration System
Using LabVIEW
Joseph Z. Xu
August 11, 2003

2. APS INSERTION DEVICES
The magnetic field spatial distribution profiles of the APS Insertion Devices (ID) are characterized with Hall Probe Magnetic Measurement System

3. Hall Effect and Hall ProbeI B
Electric current + _
Magnetic
field V H B V H I
Hall Effect
Hall Probe
Hall Probes are used to characterize the magnetic field spatial distribution profiles of the APS Insertion Devices (ID)
The Hall Probe Calibration System is designed to calibrate the Hall Probes

4. Hall Probe Calibration System
The Hall Probe Calibration System consists of:
Dry Cooper
A Magnetic
Power Supply
(MPS-853)
An Electrical
Magnet
GPIB
An NMR
Teslameter
(PT-2025)
A Reference
Teslameter
(DTM-141)
RS-232
A Motorized
Probe Stage
(SmartMotor)
A Multimeter
(HP-3458A)

5. NMR Theory of OperationB
Applied magnetic field
Spinning
nucleus
Precessionnal
orbit
Ground State
Excited State
ΔE = μB/I;
f = ΔE/h = GB;
G = μ/hI;
B: static magnetic field
I: spin quantum number
μ: nuclear magnetic moment
f: resonance frequency

6. Electric Magnet Top View
Operation Procedure
DTM-141 Probe
Calibrating Hall Probe
NMR Probes
1 2 3
4 5 6
Electric Magnet
Motorized stage
Electric Magnet Top View
I’MPS
B’EM
B DTM
IMPS
B EM
PSM
B NMR
VHall

7. What is LabVIEW? A graphical programming language
Compiled graphical development environment
Similar to flowcharting

8. Block Diagram: Source Code
Virtual Instrument
Each program is called a Virtual Instrument (VI)
Each VI has a Front Panel and a Block Diagram
Front Panel: User Interface
(MEDM)
Block Diagram: Source Code
(IOC Application)

9. Front Panel: User Interface
Graphical user interface
Pre-built user interface objects

10. Block Diagram: Source Code
Intuitive flowchart-like code
Hundreds of pre-built measurement subVIs
Self-documenting

11. Debugging
Step in, single step, step out
Highlight execution

12. Application Builder Compiler Creates: Installer Creates
Application.exe and
Application.ini files
Installer Creates
data.cab, install.msi
InstMsi.exe, setup.ini,
InstMsiW.exe, and
setup.exe files

13. Hall Probe Calibration System Software
Main Panel

14. Hall Probe Calibration System Software
Reference
Teslameter
(DTM-141)
DTM-141 Reference Digital Teslameter Panel

15. Hall Probe Calibration System Software
NMR Teslameter
(PT-2025)
PT-2025 NMR High Precision Teslameter Panel

16. Hall Probe Calibration System Software
Magnetic Power Supply
(MPS-853)
MPS-853 Magnetic Power Supply Panel

17. Hall Probe Calibration System Software
MPS-853
Magnetic
Power
Supply
Panel
Interlock
Pull
Down
Menu

18. Hall Probe Calibration System Software
Multimeter
(HP-3458A)
HP-3458A Panel

19. Hall Probe Calibration System Software
Motorized Probe Stage
(SmartMotor)
Motorized NMR Probe Stage Panel

20. Hall Probe Calibration System Software
Plot Panel

21. Hall Probe Calibration System Contents
System Hardware:
Danfysik System 8000 MPS-853 Precision Magnet Power Supply System
Electric Magnet
Metrolab PT-2025 High Precision NMR Teslameter System
Motorized NMR Probe Support Stage System Powered by Animatics SmartMotor Servo Motors
Group 3 DTM-141 Digital Teslameter System
HP 3458A Multimeter System
PC with a GPIB PCI card, a RS-232 port, 600 MHz or higher CPU, 128 MB or more RAM, and 130 MB or more free HD.
System Software and Documents:
Windows XP/2K/NT/98 OS.
PC based software package with installer on a CD
User’s Guide
Operation Method of Procedure

22. Next Project: Integral (Stretch Coil) Measurement System Upgrade
Field integral (along the z direction) Theory of Operation
Vertical Component
Horizontal Component Y 4 1 X Y 3 2 4 1 3 2

23. Key System Requirements
Motion Control: SmartMotor via RS-232
2x4 axis: x(0-400mm), y(0-400mm), z(0-6000mm), w(0-360)
Motion Readout: Linear (x, y, and z) and Rotary (w) Encoders
Linear encoder resolutions: 25 μm absolute position
Rotary encoder resolutions: 0.1deg absolute angle position
Linear stage speed: up to 50 mm/s at z direction
Rotary stage speed: up to 1 revolution per second
DAQ: Coil EM Voltage Measurement
Resolution: 16 bit (5 digits)
Sampling rate: 1.5 kS/s
Synchronization: Absolute Angle Position vs. Coil Voltage Measurement w/ at 1.5 kS/s
Triggering must be done in referencing of absolute positions.
Digital I/O Noise Control: 10-7

24. Current System Architecture
System A (on the 6 meter bench)
Stepping Motor Drivers
Stepping Motor Power Supplies
To the Stepping Motors
VME
VME44
w-Encoder
Board
VMEX
xyz-Encoder
Board
PCI
NIVXI
From the encoders
PCI
GPIB
Magnetic Flux
Integrator
Amplifier
From the Coil
Current Issues:
Flux start point and finish points (positions) are not well defined.
Only 4 data points are measured and data analysis is not feasible.
System is Windows 3.1 based and software is not upgradeable.

25. Current System Architecture
System B (on the 3 meter bench)
To the SmartMotors
From the Coil
RS-485
RS-232 to
RS-485 Converter
RS-232
PowerDAQ 16 bit
PCI ADC Card
Amplifier
Current Issues:
Positioning and measurements are “synchronized” by PC CPU time using software. (~ 3 ms?)
Start and Finish positions/times are not well defined.
System is RedHat Linux based and hard to maintain.

26. Proposed System Architecture
From x, y, z, and w
encoders
TCP/IP
PXI
FPGA I/O
w/ built in
16 bit ADC
From the Encoders
From the Coils
RS-232
To the SmartMotors
Key Features:
Integrated real time encoder readout, triggering, and Coil voltage measurement.
TCP/IP Interface, securely access the system remotely, anywhere, anytime.
Commercial off-the-shelf components.
Same hardware can be used for both 6 meter bench and 3 meter bench Hall Probe Measurement Systems.

27. Why PXI? PXI: PCI eXtensions for Instrumentation
A specification designed explicitly for industrial test and control applications.
Industry open standardized PCI backplane at 132 MB/s or 1 Gbps (32 plus integrated timing and triggering.
Well supported by all major operating systems.
Large selection of instruments and modules.
Low cost and ease of use.
See for detailed specifications

28. Hall Probe Calibration System Demo Diagram
Conclusion
For isolated control and data acquisition systems, PC based and/or PXI based platform with LabVIEW, Visual Basic, or Visual C++ development tools shall be adequate.
Hall Probe Calibration System Demo Diagram
TCP/IP
RS-232
802.11
SmartMotor
NMR Probes
GPIB
Magnetic
Power Supply
(MPS-853)
Reference
Teslameter
(DTM-141)
NMR
Teslameter
(PT-2025)
Digital
Multimeter
(HP-3458A)
Electric
Magnet