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

Hall Probe Calibration SystemUsing LabVIEW

Joseph Z. XuAugust 11, 2003

APS INSERTION DEVICES

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

Hall Effect and 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

I

I

B

Electric current

+++

++

+___

__

_

Magnetic

field

VH

BVH

I

Hall Effect Hall Probe

Hall Probe Calibration System

The Hall Probe Calibration System consists of:

A ReferenceTeslameter(DTM-141)

An ElectricalMagnet

A MagneticPower Supply

(MPS-853)

A MotorizedProbe Stage(SmartMotor)

An NMRTeslameter

(PT-2025)

A Multimeter(HP-3458A)

RS-232

GPIB

Dry Cooper

NMR Theory of Operation

B

Applied magnetic field

Spinningnucleus

Precessionnalorbit

B

Ground State Excited State

ΔE = μB/I; f = ΔE/h = GB;

μ: nuclear magnetic moment

f: resonance frequency

G = μ/hI;

B: static magnetic field

I: spin quantum number

Operation Procedure

I’MPS B’E

MB

DTM

IMPS B EM

PSM

B NMR

VHall

DTM-141 ProbeCalibrating Hall Probe

NMR Probes

1 2 3 4 5 6Electric Magnet

Motorized stage

Electric Magnet Top View

What is LabVIEW?A graphical programming

language

• Compiled graphical development environment

• Similar to flowcharting

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)

Front Panel: User Interface

• Graphical user interface• Pre-built user interface

objects

Block Diagram: Source Code

• Intuitive flowchart-like code• Hundreds of pre-built measurement

subVIs• Self-documenting

Debugging

Highlight execution

Step in, single step, step out

Application Builder

Compiler Creates:

Application.exe andApplication.ini files

Installer Createsdata.cab, install.msiInstMsi.exe,

setup.ini,InstMsiW.exe, andsetup.exe files

Main Panel

Hall Probe Calibration System Software

DTM-141 Reference Digital Teslameter Panel

ReferenceTeslameter(DTM-141)


PT-2025 NMR High Precision Teslameter Panel

NMR Teslameter(PT-2025)


MPS-853 Magnetic Power Supply Panel

Magnetic Power Supply

(MPS-853)


MPS-853 MagneticPower Supply PanelInterlock Pull Down Menu


HP-3458A Panel

Multimeter(HP-3458A)


Motorized NMR Probe Stage Panel

Motorized Probe Stage(SmartMotor)


Plot Panel


System Hardware:

Hall Probe Calibration System Contents

1. Danfysik System 8000 MPS-853 Precision Magnet Power Supply System

2. Electric Magnet3. Metrolab PT-2025 High Precision NMR Teslameter System4. Motorized NMR Probe Support Stage System Powered by

Animatics SmartMotor Servo Motors5. Group 3 DTM-141 Digital Teslameter System6. HP 3458A Multimeter System7. 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:

1. Windows XP/2K/NT/98 OS.2. PC based software package with installer on a CD3. User’s Guide4. Operation Method of Procedure

Next Project: Integral (Stretch Coil) Measurement System Upgrade

Vertical Component

Field integral (along the z direction) Theory of Operation

Horizontal Component

dzBI yy

dzBI xx

X

Y

43214

1yI

43214

1xI

1

23

4

Y

1

23

4

• 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

Key System Requirements

PCIGPIB

Current System Architecture

PCINIVXI

From the Coil

VME

System A (on the 6 meter bench)

Current Issues:

1. Flux start point and finish points (positions) are not well defined.2. Only 4 data points are measured and data analysis is not feasible.3. System is Windows 3.1 based and software is not upgradeable.

VME44w-Encoder

Board

VMEXxyz-Encoder

Board

Magnetic FluxIntegrator

Amplifier

To the Stepping MotorsStepping Motor Drivers

Stepping Motor Power Supplies

From the encoders

Current System Architecture

PowerDAQ 16 bitPCI ADC Card

From the CoilTo the SmartMotors

RS-232

RS-485

RS-232 toRS-485 Converter

Amplifier

System B (on the 3 meter bench)

Current Issues:

1. Positioning and measurements are “synchronized” by PC CPU time using software. (~ 3 ms?)

2. Start and Finish positions/times are not well defined.3. System is RedHat Linux based and hard to maintain.

Proposed System Architecture

Key Features:

1. Integrated real time encoder readout, triggering, and Coil voltage measurement.

2. TCP/IP Interface, securely access the system remotely, anywhere, anytime.

3. Commercial off-the-shelf components.4. Same hardware can be used for both 6 meter bench and 3 meter bench

Hall Probe Measurement Systems.

From x, y, z, and wencoders

From the Coils

To the SmartMotorsRS-232

PXI FPGA I/Ow/ built in16 bit ADC

TCP/

IP

From the Encoders

Why PXI?

PXI: PCI eXtensions for Instrumentation

1. A specification designed explicitly for industrial test and control applications.

2. Industry open standardized PCI backplane at 132 MB/s or 1 Gbps (32 bits@33MHz) plus integrated timing and triggering.

3. Well supported by all major operating systems.

4. Large selection of instruments and modules.5. Low cost and ease of use.See www.pxisa.org for detailed specifications

http://www.pxisa.org/

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

MagneticPower Supply

(MPS-853)

ReferenceTeslameter(DTM-141)

NMRTeslameter(PT-2025)

DigitalMultimeter(HP-3458A)

ElectricMagnet

SmartMotorNMR Probes

RS-232

GPIB

TCP/IP802.1

1

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

Documents

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