Transcript Gestaltungsrichtlinien PowerPoint_Sartorius

Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Sartorius Susceptometer - for Precise Measurement of:
Susceptibility and Magnetization of Weights
Benno Gatzemeier
Market Manager Mass Metrology
Sartorius AG / Germany
June 2007
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Contents
: Introduction – Magnetic Properties of weights
: Susceptometer Method
: The Sartorius Susceptometer
: Calibration Procedure and Factory Calibration
: Long term stability of md
: Comparison Measurement
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Introduction
Influence Parameters in Mass Comparison :
•
•
•
•
•
Air buoyancy
Contamination
Air draft
Object temperature
Magnetic properties
The golden rule in metrology is:
Factors that influence the measurement
are switched off, kept constant or considered.
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Magnetic properties
The OIML R111 recommends to check the magnetic properties.
Magnetization
Susceptibility
Standard Weights with a Susceptibility
N
S
F
Magnetic Forces
N
S
Magnet
Magnetic Forces
Standard Weight
with Magnetization
F
N
S
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: The new OIML R111
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Susceptibility  and Magnetization 0M (µT)
Magnetization 0M (µT)
Susceptibility 
Fz
Fz
H
F 
z
H
0
 ( M  (    a ) H )  z
µ0V 
Fz 
  H  HdV
2 z
H - Hz
dV

 µ0 M z
H z dV

z
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Recommended methods regarding the R111
Weight
5000 kg
1000 kg
100 kg
50 kg
100 g
50 g
10 g
2g
1g
1 mg
OIML new R111 Table B.3(b)-Susceptibility
E1
E2
F1
F2
S* / F / A
S/ F
S/ F/ A
S
S
Sp
Sp
S* / F / A
S* / F / A
S/ F/ A
S/ F/ A
S/ A
S/ A
Sp
Sp
S Susceptometer
S* F and A are prefered
F fluxgate + permanent magnet
A attracting method
Sp material specification
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Recommended methods regarding the R111
Gauss meter
Permeability Indicator
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: The Susceptometer Principe - Regarding the OIML R111
Susceptibility:
 =f (Fa...)
Fa =
F1
F2
F1 = -  m1 * g
Magnetization:
F1 + F2
2
F2 = -  m2 * g
µ0MZ =f (Fb...)
Fb =
F1 - F2
2
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: The Susceptometer Principe - Regarding the OIML R111
The R111 describes methods for the determination of the magnetic properties.
One of them is the Susceptometer principle.
A) Magnet
B) Weighing Pan
C) Bridge
D) Gauge blocks
E) Test Weight
F) Pedestal
F
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Sartorius Suszeptometer
The building guidance was the R111:
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A micro mass comparator
Internal magnet
5 different distances Z0
Load plate for weights up to 50 kg
Software to compute the formulae
Determination of:
- Susceptibility “ “
- Magnetization “0M” (T)
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Vertical Distances Z0; Magnet <-> Weight
This is important to avoid permanent magnetization.
Magnet with md produces a maximum field H
Distance may be reduced only if the Susceptometer
Field H should not exceed initially:
signal is too weak.
H  2000 A/m when testing class E1
md
H
H  800 A/m when testing class E2
2π  Z 03
H  200 A/m for classes F1 and F2.
Table 1: Initial values for testing class E1, E2, F1 and F2,
Am2
Marking Colour of
Nominal
Field
Class
marking Z0 in mm H in A/m
E1
E2
F1
Z5
Z4
Z3
Z2
Z1
Green
Yellow
Yellow
Red
Red
43
35
27
20
18
200
360
800
2000
2700
magnetic (dipole) moment md
F2
0.1
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Computation factors for Susceptibility and Magnetization:
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Weighing Result of the Magnet
H
Distance Z0 : Magnet <-> Weight H
Geometry of the test weight
S
magnetic (dipole) moment md [Am2] S
gravitational acceleration [m/s2]
S
Local magnet field BEZ –48-60 [µT] S
To measure the Magnetization,
we have to rotate the magnet!
H
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Calculation of the Magnetic properties
Calculation of the susceptibility
( Rw / Zo )2
 Zo  1 
3
Ia  1    
3
 Z1   Rw 2 
1  ( ) 
 Zo 
4

Fa
I a  Fmax  0.4  Fa
Fa 
F1  F2
2
3μ0 md2
Fmax 
 4
64π Z 0
Calculation of the Magnetization
µ0 M Z 
Fb
md I b

Z 0 4


BEZ
1  0.23
F1  F2
Fb 
2

 Rw



Z
 o

I b  2

   R w
 1   Z
   o




2




2
( Rw / Z1 )2
 Zo  1 
3
  
3
 Z1   Rw 2 
1  ( ) 
 Z1 
4

 Rw   Z1  
  /  
Z  Z 
o
o
     3/ 2 
  R / Z 2  
1   w o   
  Z 1 / Z o   

 
2




3/ 2
3
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: The vertical rotation mechanics of the magnet
• Changes the orientation of the
magnet
• Parts:
Magnet
Pedestal
Gear
Knob
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Application Software
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Easy operating
Step by step guide through the measurement procedure
Initial distance is proposed
Results via a serial connection
Calculations, report and export
Recalibrating the necessary constants
Default parameters and user defined configurations
Shape description, OIML knob weights predefined
Export and import function for the sharp of the weights
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 1. Select weighing geometry
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Own cylinder - Geometry of the test weight
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 2. Input parameter
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 3. Remove test weight
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 4 Adjust vertical position Z2
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 5. Adjust test magnet to position “N”
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
6. Place
Tare balance
: 7.
test weight
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 9.
8. Remove
Determine
testmeasured
weight value m1 for Z4
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 10. Adjust test magnet to position “S”
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 12.
11. Load
Tare balance
test weight
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: 14.
13. Remove
Determine
testmeasured
weight value m2 for Z5
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Push result button
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
: Technical specifications Sartorius Susceptometer
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Base area
Height
Maximum load
Dipole moment of the magnet
Geometry ratio of the magnet
Height Z0 adjustable in fixed steps
Field strength
Readability of the Mass Comparator
Reverse gear for magnet
338 x 286 mm
249 mm
50 kg
m ~ 0.1 Am2
h/d = 0.87
Z1=18 / Z2=20 / Z3=27 / Z4=35 / Z5=43mm
2700 / 2000 / 800 / 360 / 200 A/m
10 µg or 1 µg
external rotary knob with N-S marking
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Calibration, check of the Susceptometer
1. Calibration of the Mass comparator (10 g)
2. Using a Susceptibility Reference
with certificate of the susceptibility
3. Measure the Susceptibility Reference on
the Sartorius Susceptometer
4. Compare the result of the Susceptometer
with the PTB-certificate.
5. The difference has to be less than 10%
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Factory calibration
•
We use a 1 kg stainless steel
susceptibility standard (=0.004069)
•
Additional information is used as check
for the factory calibration:
– Value of the vertical distance Z0
from the mechanical adjustments in
the manufacturing
– We use always the same three
additional magnets.
historical data (md )
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Calibration procedure / Adjustment
1. Calibration of the mass comparator
uses a 10 g weight
F1-2
2. Calibration of the dipole moment md,
uses 3 additional magnets and measure
the forces between each pair of magnets
6 equations and 4 unknown dipole moments
3. Calibration of the distance Z0,
uses a susceptibility standard at known 
F1-3
F1-4
F2-3
F2-4
F3-4
PTB
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Comparison Measurement
Our references Susceptibilities
4 x NPL Standards
1 x PTB Standard
Question: Calibration with susceptibility standard : =0.00401
Application range
: 0<1
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Our Susceptibility standards
PTB2419
NPL1005
NPL 1024
NPL11
NPL16
0.00401
0.0055
0.02657
0.1173
0.693
0.00004
0.00005
0.000205
0.00056
0.0034
H in kA/m
5.0
2.7
2.0
0.8
0.2
Diameter in mm
59
40
40
40
25
Height in mm
45
27
25
27
25
Position
Z1
Z1
Z2
Z3
Z5
U(
) k=2
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Comparison Measurement
Calibration
with
/
PTB2419
0.00401
NPL1005
0.0055
NPL 1024
0.02657
NPL11
0.1173
NPL16
0.693
PTB2419
0.0 %
-3.3 %
-4.8%
-5.2 %
-5.8 %
NPL1005
3.1%
0.0 %
-1.9 %
-2.9 %
-4.0 %
NPL1024
5.1 %
2.1%
0.0 %
-1.5 %
-2.8 %
NPL11
7.1 %
4.3 %
1.9%
0.0 %
-1.6%
NPL16
10.0 %
7.3 %
4.6 %
2.1 %
0.0 %
Cathetometer
10.7 %
8.0 %
5.3 %
2.6 %
0.4 %
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Long term stability of our reference Susceptibility 
The change of the Susceptibility is in the range of the uncertainty and less than 2 %
0,00415
Susceptibility Reference PTB 2419
0,00410
0,00405
0,00400
0,00395
0,00390
2002
2003
2004
2005
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Long term stability of our reference magnets md
Mass Metrology
Metrology, -April
Susceptometer,
2003
June 2007
Thank you for your attention
Benno Gatzemeier
Mass Metrology
Sartorius AG / Germany