IEC 60747-14-4:2011

IEC 60747-14-4 ®
Edition 1.0 2011-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Discrete devices –
Part 14-4: Semiconductor accelerometers

Dispositifs à semiconducteurs – Dispositifs discrets –
Partie 14-4: Accéléromètres à semiconducteurs

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IEC 60747-14-4 ®
Edition 1.0 2011-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Discrete devices –
Part 14-4: Semiconductor accelerometers

Dispositifs à semiconducteurs – Dispositifs discrets –
Partie 14-4: Accéléromètres à semiconducteurs
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XD
ICS 31.080.01 ISBN 978-2-88912-323-0

– 2 – 60747-14-4  IEC:2011
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terminology and letter symbols . 9
3.1 Terms and definitions . 9
3.2 Letter symbols . 15
4 Essential ratings and characteristics . 16
4.1 General . 16
4.1.1 Operating principle . 16
4.1.2 Single axis and multi-axis . 16
4.1.3 Performance evaluation . 17
4.1.4 Sensitivity . 17
4.1.5 Classification . 18
4.1.6 Symbol (g) . 19
4.1.7 Customer and supplier . 19
4.1.8 Linearity and nonlinearity . 19
4.1.9 Element materials . 19
4.1.10 Handling precautions . 20
4.1.11 Accelerometer mounting condition . 20
4.1.12 Specifications . 20
4.2 Ratings (limiting values) . 20
4.3 Recommended operating conditions . 20
4.4 Characteristics . 21
4.4.1 Measurement range . 21
4.4.2 Sensitivity and sensitivity error . 21
4.4.3 Bias (offset) and bias (offset) error . 21
4.4.4 Linearity . 21
4.4.5 Misalignment . 22
4.4.6 Cross-axis sensitivity . 22
4.4.7 Cross-coupling coefficient. 22
4.4.8 Temperature coefficient of sensitivity . 22
4.4.9 Temperature coefficient of bias. 22
4.4.10 Frequency response . 22
4.4.11 Supply current . 22
4.4.12 Output noise . 22
4.4.13 Ratiometricity . 22
4.4.14 Self test . 23
5 Measuring methods . 23
5.1 General . 23
5.1.1 Standard test conditions . 23
5.1.2 Applicable measurement methods for test and calibration method . 23
5.2 Testing methods for characteristics . 25
5.2.1 Measurement range . 25
5.2.2 Supply voltage range . 26
5.2.3 Sensitivity and sensitivity error . 26

60747-14-4  IEC:2011 – 3 –
5.2.4 Bias and bias error . 26
5.2.5 Linearity . 27
5.2.6 Misalignment . 29
5.2.7 Cross-axis sensitivity . 30
5.2.8 Cross-coupling coefficient. 30
5.2.9 Temperature coefficient of sensitivity . 31
5.2.10 Temperature coefficient of bias. 31
5.2.11 Frequency response . 31
5.2.12 Supply current . 35
5.2.13 Output noise . 35
6 Acceptance and reliability . 36
6.1 Environmental test . 36
6.1.1 High temperature storage . 36
6.1.2 Low-temperature storage . 36
6.1.3 Temperature humidity storage . 37
6.1.4 Temperature cycle . 37
6.1.5 Thermal shock . 37
6.1.6 Salt mist . 37
6.1.7 Vibration . 37
6.1.8 Mechanical shock . 37
6.1.9 Electrical noise immunity . 37
6.1.10 Electro-static discharge immunity . 37
6.1.11 Electro-magnetic field radiation immunity . 38
6.2 Reliability test. 38
6.2.1 Steady-state life . 38
6.2.2 Temperature humidity life . 38
Annex A (informative) Definition of sensitivity matrix of an accelerometer . 39
Annex B (informative) Dynamic linearity measurement using an impact acceleration
generator . 79
Annex C (informative) Measurement of peak sensitivity . 88
Bibliography . 97

Figure 1 – Single axis accelerometer . 17
Figure 2 – Multi-axis accelerometer . 17
Figure 3 – Concept of the mathematical definition of accelerometers . 18
Figure 4 – Concept of dynamic linearity of an accelerometer on gain . 28
Figure 5 – Concept of dynamic linearity of an accelerometer on phase . 29
Figure 6 – The semiconductor accelerometer as a system . 33
Figure 7 – Example of the structure of assembled semiconductor accelerometer
system for the concept of accelerometer frequency response . 34
Figure 8 – Schematic diagram of frequency response measurement by electrical input . 35
Figure A.1 – Example of direction cosine . 46
Figure A.2 – Accelerometers or pick-offs assembled in a normal co-ordinate system
(top figure) and the acceleration component projection to the three co-ordinate axis
plains, XY, YZ and ZX (bottom figure) . 53
Figure B.1 – Set-up for dynamic linearity measurement . 86
Figure C.1 – Peak sensitivity as a function of each frequency bandwidth from DC to f . 88
n
Figure C.2 – Set-up for the control of frequency bandwidth of shock acceleration . 96

– 4 – 60747-14-4  IEC:2011
Table 1 – List of letter symbols . 15
Table 2 – Level of accelerometers and the definition . 18
Table 3 – Test items and the recommended corresponding measurement methods . 24
Table 4 – Relation between recommended applicable calibration methods and type of
accelerometers . 25
Table A.1 – Symbols for the relationship between input acceleration and the output
signal from an accelerometer using one-dimensional vibration table . 46
Table A.2 – Symbols for input acceleration and output signals from an accelerometer . 47
Table A.3 – Definition of symbols for describing the input acceleration, output signal
from the target accelerometer and the direction cosine repeated three times . 47
Table A.4 – Relationship between the expression of transfer function in a matrix form
and the number of axis of the target accelerometers . 49
Table A.5 – Definition of vector space related to the generalization of the transverse
sensitivity using the vector space concept . 57
Table A.6 – Relation between input acceleration and output signal for the calibration,
using the six-dimensional vibration table . 59
Table A.7 – Normal sensitivities, explicit cross-sensitivities and implicit cross-
sensitivities obtained by the calibration carried out in the application acceleration
vector space with three dimensions . 75
Table A.8 – Normal sensitivities, explicit cross-sensitivities and implicit cross-
sensitivities obtained by the calibration carried out in the application acceleration
vector space with six dimensions . 76
Table A.9 – List of symbols in terms of measurement uncertainty using an
accelerometer with M output axis assuming that N is larger than M . 77
Table B.1 – Dynamic linearity when both input and output are vector quantities . 79
Table B.2 – Relations between the direction cosine of the input acceleration to one-
axis accelerometers and the signal from the output axis . 80
Table B.3 – Relationship between the direction cosine of the input acceleration to one-
axis accelerometers and the signal from the output axis . 81
Table B.4 – Conditions on the direction cosine for dynamic linearity measurement . 82
Table B.5 – Relations between the direction cosine of the input acceleration to two-
axis accelerometers and the signal from the output axis . 82
Table B.6 – Relations between the direction cosine of the input acceleration to two-
axis accelerometers and the signal from the output axis . 83
Table B.7 – Conditions on the direction cosine for the dynamic linearity measurement . 83
Table B.8 – Relationship between the direction cosine of the input acceleration to
three-axis accelerometers and the signal from the output axis . 84
Table B.9 – Relations between the direction cosine of the input acceleration to three-
axis accelerometers and the signal from the output axis . 85
Table B.10 – Conditions on the direction cosine for dynamic linearity measurement . 85
Table C.1 – Definition of elements in one-axis accelerometer peak sensitivity . 88
Table C.2 – Peak sensitivity of one-axis accelerometer . 89
Table C.3 – Relationship of direction cosine and the co-ordinate system of the target
accelerometer . 89
Table C.4 – Definition of elements in two-axis accelerometer peak sensitivity . 91
Table C.5 – Definition of elements in three-axis accelerometer peak sensitivity . 93

60747-14-4  IEC:2011 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
DISCRETE DEVICES –
Part 14-4: Semiconductor accelerometers

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
International Standard IEC 60747-14-4 has been prepared by subcommittee 47E: Discrete
semiconductor devices, of IEC technical committee 47: Semiconductor devices.
This part of IEC 60747 should be read in conjunction with IEC 60747-1:2006. It provides basic
information on semiconductor
– terminology;
– letter symbols;
– essential ratings and characteristics;
– measuring methods;
– acceptance and reliability.
– 6 – 60747-14-4  IEC:2011
The text of this standard is based on the following documents:
FDIS Report on voting
47E/405/FDIS 47E/409/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 60747 series, under the general title Semiconductor devices –
Discrete devices, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
60747-14-4  IEC:2011 – 7 –
INTRODUCTION
The International Electrotechnical Commission (IEC) draws attention to the fact that it is
claimed that compliance with this document may involve the use of a patent concerning
following items.
a) Measurement technique and apparatus for matrix sensitivity in “definition of sensitivity
matrix of an accelerometer” given in Subclause 4.1.5 and Annex A.
b) Measurement technique and apparatus for the dynamic linearity measurement of AC
accelerometers in “dynamic linearity measurement using an impact acceleration
generator” given in Annex B.
c) Measurement technique and apparatus for the frequency response measurement of
accelerometers under the frequency bandwidth control in “method of controlling the
frequency bandwidth of the shock acceleration” given in Clause C.5.
d) Measurement technique and apparatus for the dynamic response and peak sensitivity
measurement of accelerometers in the form of matrix using elastic pulse in “definition of
sensitivity matrix of an accelerometer” given in Annex A.
e) Projectiles for frequency bandwidth control in “method of controlling the frequency
bandwidth of the shock acceleration” given in Clause C.5 and for the dynamic response
and peak sensitivity measurement of accelerometers in the form of matrix using elastic
pulse in “definition of sensitivity matrix of an accelerometer” given in Annex A.
IEC takes no position concerning the evidence, validity and scope of this patent right.
The holder of these patent rights has assured the IEC that he/she is willing to negotiate
licences under reasonable and non-discriminatory terms and conditions with applicants
throughout the world. In this respect, the statement of the holder of this patent right is
registered with IEC. Information may be obtained from:
Name: Intellectual Planning Office, Intellectual Property Department, National Institute of
Advanced Industrial Science and Technology
Address: 1-1-1, Umezono, Tsukuba-shi, Ibaraki, 305-8564, Japan.

Name: VectorDynamics Corporation
Address: 1-11-7 Higashikanda, Chiyoda-ku, Tokyo, 101-0031, Japan.
Heights Kanda Iwamotocho #305
Attention is drawn to the possibility that some of the elements of this document may be the
subject of patent rights other than those identified above. IEC shall not be held responsible for
identifying any or all such patent rights.
ISO (www.iso.org/patents) and IEC (http://www.iec.ch/tctools/patent_decl.htm) maintain on-
line data bases of patents relevant to their standards. Users are encouraged to consult the
data bases for the most up to date information concerning patents.

– 8 – 60747-14-4  IEC:2011
SEMICONDUCTOR DEVICES –
DISCRETE DEVICES –
Part 14-4: Semiconductor accelerometers

1 Scope
This part of IEC 60747 applies to semiconductor accelerometers for all types of products.
This standard applies not only to typical semiconductor accelerometers with built-in electric
circuits, but also to semiconductor accelerometers accompanied by external circuits.
This standard does not (or should not) violate (or interfere with) the agreement between
customers and suppliers in terms of a new model or parameters for business.
NOTE 1 This standard, although directed toward semiconductor accelerometers, may be applied in whole or in
part to any mass produced type of accelerometer.
NOTE 2 The purpose of this standard is to allow for a systematic description, which covers the subjects initiated
by the advent of semiconductor accelerometers. The tasks imposed on the semiconductor accelerometers are not
only common to all accelerometers but also inherent to them and not yet totally solved. The descriptions are based
on latest research results. One typical example is the multi-axis accelerometer. This standard states the method of
measuring acceleration as a vector quantity using multi-axis accelerometers.
NOTE 3 This standard does not conflict in any way with any existing parts of either ISO 16063 or ISO 5347. This
standard intends to provide the concepts and the procedures of calibration of the semiconductor multi-axis
accelerometers which are used not only for the measurement of acceleration but also for the control of motion in
the wide frequencies ranging from DC.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60747-1:2006, Semiconductor devices – Part 1:General
IEC 60749 (all parts), Semiconductor devices – Mechanical and climate test methods
IEC 60749-1, Semiconductor devices – Mechanical and climate test methods – Part 1:
General
IEC 60749-5, Semiconductor devices – Mechanical and climatic test methods – Part 5:
Steady-state temperature humidity bias life test
IEC 60749-6, Semiconductor devices – Mechanical and climatic test methods – Part 6:
Storage at high temperature
IEC 60749-10, Semiconductor devices – Mechanical and climatic test methods – Part 10:
Mechanical shock
IEC 60749-11, Semiconductor devices – Mechanical and climatic test methods – Part 11:
Rapid change of temperature – Two-fluid-bath method

60747-14-4  IEC:2011 – 9 –
IEC 60749-12, Semiconductor devices – Mechanical and climatic test methods – Part 12:
Vibration, variable frequency
IEC 60749-13, Semiconductor devices – Mechanical and climatic test methods – Part 13: Salt
atmosphere
IEC 60749-25, Semiconductor devices – Mechanical and climatic test methods – Part 25:
Temperature cycling
IEC 61000-4 (all parts), Electromagnetic compatibility (EMC) – Part 4: Testing and
measurement techniques
IEC 61000-4-2:1995, Electromagnetic compatibility (EMC) – Part 4-2: Testing and
measurement techniques – Electrostatic discharge immunity test
IEC 61000-4-3:2006, Electromagnetic compatibility (EMC) – Part 4-3: Testing and
measurement techniques – Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4:2004, Electromagnetic compatibility (EMC) – Part 4:Testing and measurement
techniques – Section 4: Electrical fast transient/burst immunity test
ISO 5347 (all parts), Methods for the calibration of vibration and shock pick-ups
ISO 5347-11:1993, Methods for the calibration of vibration and shock pick-ups – Part 11:
Testing of transverse vibration sensitivity
ISO/IEC Guide 99, International vocabulary of metrology – Basic and general concepts and
associated terms (VIM)
3 Terminology and letter symbols
3.1 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1.1
accelerometer
device whose output is a vector representing the projection of the acceleration in a
multidimensional space of the acceleration applied to it
3.1.2
AC accelerometer
accelerometer which has a high-pass filter in either real or equivalent signal processing
circuits in characteristics
NOTE It responds to AC band domain input in its frequency characteristics. This type of accelerometer is useful
for measurement of vibration, shock and sway.
3.1.3
DC accelerometer
accelerometer that responds to the input from DC to specified AC band domain in its
frequency characteristics
NOTE It has the second order open-loop system or closed-loop system. This type of accelerometer is useful for
measurement of inclination angle, velocity and displacement by integration of output.

– 10 – 60747-14-4  IEC:2011
3.1.4
semiconductor accelerometer
accelerometer manufactured by the semiconductor technology for at least one acceleration
sensing element
NOTE A typical example might be a combination of a silicon seismic system by micro-machining with sensing
mechanism and an electrical circuit.
3.1.5
one-dimensional accelerometer
accelerometer whose characteristics are measured in the calibration acceleration vector
space with dimension one
3.1.6
two-dimensional accelerometer
accelerometer whose characteristics are measured in the calibration acceleration vector
space with dimension two
3.1.7
three-dimensional accelerometer
accelerometer whose characteristics are measured in the calibration acceleration vector
space with dimension three
3.1.8
four-dimensional accelerometer
accelerometer whose characteristics are measured in the calibration acceleration vector
space with dimension four
3.1.9
five-dimensional accelerometer
accelerometer whose characteristics are measured in the calibration acceleration vector
space with dimension five
3.1.10
six-dimensional accelerometer
accelerometer whose characteristics are measured in the calibration acceleration vector
space with dimension six
3.1.11
level 1 accelerometer
accelerometer with a sensitivity that is not defined in a form of a matrix
NOTE The sensitivity along the input axis is separated from the cross axis sensitivity.
3.1.12
level 2 accelerometer
accelerometer with sensitivity in the form of a matrix in which all components of the matrix are
constant as a function of frequency and other parameters if necessary
3.1.13
level 3 accelerometer
accelerometer with sensitivity in the form of a matrix in which some of the components are
defined as functions of frequency and other parameters if necessary
3.1.14
level 4 accelerometer
accelerometer with sensitivity in the form of a matrix in which all of the components are
defined as functions of frequency and other parameters if necessary

60747-14-4  IEC:2011 – 11 –
3.1.15
input acceleration vector space
real motion vector space where the input acceleration is an element of a set
NOTE Input acceleration vector space is divided into the application acceleration vector space and the calibration
acceleration vector space.
3.1.16
accelerometer output vector space
vector space where the output signal from an accelerometer is an element of a set
3.1.17
gravitational acceleration
acceleration due to gravity
NOTE The symbol g denotes a unit of acceleration equal in magnitude to the value of local gravity and the symbol
g represents the standard value of g under international agreement, g =9,80665 m/s .
n n
3.1.18
input axis
axis along or about which the accelerometer output for the applied acceleration indicates a
maximum value
NOTE Neither misalignment nor cross-axis sensitivity compensation is employed. The IA direction only may be
marked on the external package.
3.1.19
input reference axis
direction of an axis that is nominally parallel to the input axis
NOTE It is defined by the package mounting surfaces or external package markings.
3.1.20
output axis
axis along or about which the output of the accelerometer is measured
NOTE In some cases, it is referred to as the hinge or flexure axis.
3.1.21
output reference axis
direction of an axis that is nominally parallel to the output axis
NOTE It is defined by the package mounting surfaces or external package markings.
3.1.22
pendulum axis
axis through the proof mass centre in pendulum accelerometers
NOTE It is perpendicular to and intersecting the output axis.
3.1.23
pendulum reference axis
direction of an axis that is nominally parallel to the pendulum axis
NOTE It is defined by the package mounting surfaces or external package markings.
3.1.24
misalignment
angle between an input axis and the corresponding input reference axis that is indicated on
the accelerometer package, when the device is at a 0 g position

– 12 – 60747-14-4  IEC:2011
3.1.25
pick-off
device that indicates the displacement of proof mass generated by input acceleration
3.1.26
proof mass
mass whose inertia produces an acceleration signal
NOTE Pendulum-mass or translational-mass is generally used.
3.1.27
bias
outputs without any acceleration along the input axis
NOTE It may be represented by the algebraic means between the peak outputs given when acceleration is
applied equally along both directions of the input axis.
3.1.28
bias discrepancy
difference between the bias values at the 1 g and the 0 g positions
NOTE It is a function of the non-linear characteristics of sensitivity.
3.1.29
bias error
algebraic difference between the bias of a device and the nominal bias in the specification
NOTE The bias specification of the device is comprised of the variation due to temperature and voltage.
3.1.30
temperature coefficient of bias
change in bias per unit change in temperature relative to the bias at the specified temperature
3.1.31
ratiometricity
proportionality of the output acceleration to the supply voltage change on the accelerometer
3.1.32
supply voltage range
maximum and minimum supply voltage values among which the device can operate normally
3.1.33
measurement range
maximum and minimum acceleration values that are measurable
3.1.34
input acceleration limits
extreme values of the input acceleration, within which the accelerometer can keep the
specified performance
3.1.35
first resonant frequency
lowest frequency at which the ratio of output versus input acceleration takes a peak value
3.1.36
dynamic linearity
linearity that is concerned with the relationship between the transient input signals and output
signals
NOTE See Annex B.
60747-14-4  IEC:2011 – 13 –
3.1.37
sensitivity matrix
matrix that transforms the input acceleration vector space to the output signal vector space
under the assumption that the transformation is linear
NOTE 1 Diagonal terms and non-diagonal terms correspond to normal sensitivities and cross-sensitivities,
respectively.
NOTE 2 Calibration of an accelerometer should be recognized as the process of determining all of the
components of the sensitivity matrix.
NOTE 3 Matrix sensitivity can be used to describe the sensitivity of accelerometers of level 2, 3 and 4. It is used
to place an emphasis on the difference between the conventional sensitivity of the level 1 and level 2, 3 and 4
accelerometers (see 4.1.5: Classification)
3.1.38
peak sensitivity matrix
matrix with the components of peak sensitivity considered along the normal sensitivity axis as
the diagonal terms and the components of peak sensitivity considered along the cross-
sensitivity axis as the non-diagonal terms
3.1.39
sensitivity
output change per unit change of input acceleration in either static or dynamic state
NOTE 1 Sensitivity in steady state of level 1 accelerometers is generally evaluated as the slope of the straight
line that can be fitted by the least square method applied to input-output data obtained by varying the input within
the measurement range.
NOTE 2 Sensitivity for level 2, 3 and 4 accelerometers is expressed by a matrix.
3.1.40
sensitivity error
algebraic difference between a sensitivity of a device and the nominal sensitivity in the
specification, with the percentage expression applied with the nominal sensitivity
NOTE The sensitivity of the device possesses the maximum and the minimum values among the over-all figures
containing the temperature coefficient, etc.
3.1.41
temperature coefficient of sensitivity
change in sensitivity per unit change in temperature relative to the sensitivity at the specified
temperature
3.1.42
normal sensitivity
sensitivity defined along the axis with the maximum sensitivity of an accelerometer
3.1.43
cross-sensitivity
sensitivity defined by the output along the specified axis perpendicular to the input along the
normal sensitivity axis
3.1.44
cross-axis sensitivity
maximum sensitivity in the plane perpendicular to the measuring direction relative to the
sensitivity in the measuring direction
NOTE 1 The maximum sensitivity in the perpendicular plane is obtained as the geometric sum of the sensitivities
in two perpendicular directions in this plane.
NOTE 2 Transverse sensitivity can be used in stead of cross-axis sensitivity.

– 14 – 60747-14-4  IEC:2011
3.1.45
cross-coupling coefficient
ratio of the variation of accelerometer output to the product of acceleration applied normal
and parallel to an input reference axis
3.1.46
peak sensitivity
value as the ratio of the maximum output signal divided by the maximum input acceleration
NOTE See Annex C.
3.1.47
frequency response of sensitivity
ratio of the output signal to the applied acceleration at discrete frequency or in narrow
bandwidth as a function of frequency
3.1.48
frequency response of cross-sensitivity
ratio of the output signal to the applied acceleration at discrete frequency or in narrow
bandwidth in orthogonal direction as a function of frequency
3.1.49
Doppler shift interferometer
interferometer based on Doppler shift principle
3.1.50
laser interferometer
system that measures a motion by means of an optical interference using a laser as a light
source
NOTE It serves for the primary calibration of accelerometers.
3.1.51
strain gauge
sensor that electrically detects the strain
3.1.52
uncertainty
parameter, associated with the result of a measurement, that characterizes the dispersion of
the values that could reasonably be attributed to the measurand
NOTE See Guide to the expression of uncertainty in measurement.

60747-14-4  IEC:2011 – 15 –
3.2 Letter symbols
For the purposes of this document, letter symbols given in Table 1, apply.
Table 1 – List of letter symbols
Name and designation Letter symbol Remarks
Acceleration:
– at input points of j = 1,···, n a
j
– of a positive specific input to DC accelerometer a
+
– of a negative specific input to DC accelerometer a
−
– of a specific input to AC accelerometer a
rms
– of a positive maximum input a
max
– of a negative maximum input a
min
– due to local gravity g
– due to standard gravity g g = 9,806 65 m/s
n n
Accelerometer output:
– in accelerometer output units E
– at input-acceleration points of j = 1,···, n E
j
– at a positive specific input a E
+ +
E
– at a negative specific input a
−
−
– at a specific input arms E
rms
– at the UP(+1 g) position E
up
– at the DOWN(–1 g) position E
down
Bias:
– apparent value B’
B
– in the high temperature operating condition
high
– in the low temperature opera
...