SIST EN 61143-1:1999
(Main)Electrical measuring instruments - X-t recorders -- Part 1: Definitions and requirements
Electrical measuring instruments - X-t recorders -- Part 1: Definitions and requirements
Applies to X-t recorders used for the measurement of voltage and current which measure and record analogue electrical quantities as a function of time. Also applies to non-interchangeable accessories and accessories of limited interchangeability (e.g. shunts, impedance-elements) if they are used with the recorder and the adjustments have been made for the combination. IEC 61143-1 and IEC 61143-2 cancel and replace EN 60484 (1974).
Elektrische Meßgeräte - X-t-Schreiber -- Teil 1: Definitionen und Anforderungen
Appareils électriques de mesure - Enregistreurs X-t -- Partie 1: Définitions et prescriptions
S'applique aux enregistreurs X-t destinés à la mesure d'une tension ou d'un courant qui mesurent et enregistrent des grandeurs électriques analogiques en fonction du temps. S'applique également aux accessoires non interchangeables ou à interchangeabilité limitée (par exemple shunt, élément d'impédance) s'ils sont utilisés avec l'enregistreur et si les réglages ont été effectués avec l'association des deux. Les CEI 61143-1 et 61143-2 annulent et remplacent la EN 60484.
Električni merilni instrumenti – Zapisovalniki X-t – 1. del: Definicije in zahteve (IEC 61143-1:1992)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 61143-1:1999
01-julij-1999
(OHNWULþQLPHULOQLLQVWUXPHQWL±=DSLVRYDOQLNL;W±GHO 'HILQLFLMHLQ]DKWHYH ,(&
Electrical measuring instruments - X-t recorders -- Part 1: Definitions and requirements
Elektrische Meßgeräte - X-t-Schreiber -- Teil 1: Definitionen und Anforderungen
Appareils électriques de mesure - Enregistreurs X-t -- Partie 1: Définitions et
prescriptions
Ta slovenski standard je istoveten z: EN 61143-1:1994
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
SIST EN 61143-1:1999 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
NORME
CEI
INTERNATIONALE
IEC
61143-1
INTERNATIONAL
Première édition
STAN DARD
First edition
1992-06
Appareils électriques de mesure –
Enregistreurs X-t
Partie 1:
Définitions
et prescriptions
Electrical measuring instruments –
X-t recorders
Part 1:
Definitions and requirements
© IEC 1992 Droits de reproduction réservés Copyright - all rights reserved
—
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit any form or by any means, electronic or mechanical,
et par aucun
procédé, électronique ou mécanique, compris including photocopying and microfilm, without permission in
y la photo-
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http: //www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
V
PRICE CODE
International Electrotechnical Commission
IEC Me ayHapogHeR 3neeTpoTexHH4ecnac HOMHCCHfI
Pour prix, voir catalogue en vigueur
• • For price, see current catalogue
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_ 3 _
1143-1 ©IEC
CONTENTS
Page
FOREWORD 7
Clause
1 Scope 9
2 Normative references 9
3 Definitions
13
3.1 General terms 13
3.2 Description of recorders according to their methods of operation 17
3.3 Construction features of recorders 17
3.4 Characteristic features of recorders 21
3.5 Characteristic values 23
3.6 Influence quantities, reference conditions, nominal range of use and
preconditioning
25
3.7 Errors and variations 25
3.8 Accuracy, accuracy class, class index 27
4 Description, classification and compliance 27
4.1 Description 27
4.2 Classification 29
4.3 Compliance with the requirements of this pa
rt 29
5 Reference conditions and intrinsic errors 29
5.1 Reference conditions 29
5.2 Fiducial value and limits of intrinsic errors 29
5.3 Span
31
5.4 Dead band 31
5.5 Additional error due to zero displacement 31
6 Nominal range of use and variations 33
6.1 Nominal range of use
33
6.2 Limits of variations
33
6.3 Conditions for the determination of variations 33
6.4 Variation in timekeeping
35
6.5 Variation due to parasitic input quantities 35
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1143-1 ©I EC – 5 –
Clause Page
7 Further electrical and mechanical requirements 41
7.1 Dynamic performance 41
7.2 Continuous use 41
7.3 Permissible overloads 41
7.4 Limiting values of temperature 43
8 Constructional requirements 43
8.1 Sealing to prevent access 43
8.2 Scales and charts 43
8.3 Preferred values 45
8.4 Vibration and shock 45
9 Information, markings and symbols 47
9.1 Information on the recorder 47
9.2 Information in documentation 47
9.3 Information relating to reference conditions and nominal ranges of use 49
10 Markings and symbols for terminals 57
10.1 Requirements for markings 57
10.2 Earthing (grounding) terminals 57
10.3 Measuring circuit terminals 57
11 Tests to prove compliance with this pa rt
57
11.1 Perf
ormance 57
Annex A – Determination of the influence of parasitic input quantities 59
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1143-1 ©IEC - 7 -
INTERNATIONAL ELECTROTECHNICAL COMMISSION
ELECTRICAL MEASURING INSTRUMENTS - X-t RECORDERS
Part 1: Definitions and requirements
FOREWORD
The formal decisions or agreements of the IEC on technical matters, prepared by Technical Committees on
1)
which all the National Committees having a special interest therein are represented, express, as nearly as
possible, an international consensus of opinion on the subjects dealt with.
2) They have the form of recommendations for international use and they are accepted by the National
Committees in that sense.
3) In order to promote international unification, the IEC expresses the wish that all National Committees
should adopt the text of the IEC recommendation for their national rules in so far as national conditions will
permit. Any divergence between the IEC recommendation and the corresponding national rules should, as
far as possible, be clearly indicated in the latter.
4) The IEC has not laid down any procedure concerning marking as an indication of approval and has no
responsibility when an item of equipment is declared to comply with one of its recommendations.
This part of International Standard IEC 1143 has been prepared by IEC Technical
Committee No. 85: Measuring equipment for basic electrical quantities.
The text of this part is based on the following documents:
Six Months' Rule Report on Voting
85(Ca)15 85(CO)19
Full information on the voting for the approval of this part can be found in the Voting
Report indicated in the above table.
Annex A forms an integral part of this part.
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1143-1 © IEC - 9 -
ELECTRICAL MEASURING INSTRUMENTS - X-t RECORDERS
Part 1: Definitions and requirements
1 Scope
This part of IEC 1143 applies to X-t recorders used for the measurement of voltage and
current which measure and record analogue electrical quantities as a function of time.
It also applies to a recorder whose chart scale lines do not correspond directly to the elec-
trical input quantity, provided that the relationship between them is known.
For the measurement of other electrical quantities, the relevant parts of IEC 51 also apply.
This part also applies to non-interchangeable accessories and accessories of limited
interchangeability (e.g. shunts, impedance elements) if they are used with the recorder
and the adjustments have been made for the combination. For controllers with electrical
outputs and containing electrical recorders, this pa rt applies only to the recorder and does
not apply to the control circuit.
rt does not apply to special purpose recorders or to special purpose devices (when
This pa
they are used as accessories) which are covered by their own IEC standards.
This pa rt does not cover safety requirements (for reference, see IEC 1010) and does not
contain either requirements for protection against environmental conditions or the relevant
tests. However, when necessary, tests under conditions approaching those of use may be
selected from IEC 68, to prove protection against environmental conditions.
Further, it does not contain requirements concerning the dimensions of instruments or
accessories (for the former, see IEC 473).
2 Normative references
The following normative documents contain provisions which, through reference in
this text, constitute provisions of this pa rt of IEC 1143. At the time of publication of
this standard, the editions indicated were valid. All normative documents are subject
rties to agreements based on this part of IEC 1143 are encouraged to
to revision, and pa
investigate the possibility of applying the most recent editions of the normative
documents indicated below. Members of IEC and ISO maintain registers of currently valid
International Standards.
IEC 27, Letter symbols to be used in electrical technology.
IEC 51-1: 1984, Direct acting indicating analogue electrical measuring instruments and
their accessories - Part 1: Definitions and general requirements common to all parts.
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1143-1 ©IEC - 11 -
IEC 51-2: 1984, Direct acting indicating analogue electrical measuring instruments and
their accessories - Part 2: Special requirements for ammeters and voltmeters.
IEC 51-3: 1984, Direct acting indicating analogue electrical measuring instruments and
their accessories - Part 3: Special requirements for wattmeters and varmeters.
Direct acting indicating analogue electrical measuring instruments and
IEC 51-4: 1984,
their accessories - Part 4: Special requirements for frequency meters.
Direct acting indicating analogue electrical measuring instruments and
IEC 51-5: 1985,
5: Special requirements for phase meters, power factor meters
their accessories - Part
and synchroscopes.
Direct acting indicating analogue electrical measuring instruments and
IEC 51-6: 1984,
their accessories - Part 6: Special requirements for ohmmeters (impedance meters) and
conductance meters.
IEC 51-7: 1984, Direct acting indicating analogue electrical measuring instruments and
their accessories - Part 7: Special requirements for multi-function instruments.
Direct acting indicating analogue electrical measuring instruments and
IEC 51-8: 1984,
their accessories - Part 8: Special requirements for accessories.
Direct acting indicating analogue electrical measuring instruments and
IEC 51-9: 1988,
their accessories - Pa rt 9: Recommended test methods.
Environmental testing - Part 2: Tests - Test Fc and guidance: Vibra-
IEC 68-2-6: 1982,
tion (sinusoidal).
IEC 68-2-27: 1987, Environmental testing - Part 2: Tests - Test Ea and guidance: Shock.
IEC 160: 1963, Standard atmospheric conditions for test purposes.
Safety requirements for indicating and recording electrical measuring
IEC 414: 1973,
instruments and their accessories.
Graphical symbols for use on equipment - Index, survey and compilation
IEC 417: 1973,
of the single sheets.
Dimensions for panel-mounted indicating and recording electrical measur-
IEC 473: 1974,
ing instruments.
IEC 617-2: 1983, Graphical symbols for diagrams - Part 2: Symbol elements, qualifying
symbols and other symbols having general application.
IEC 1010, Safety requirements for electrical equipment for measurement, control and
laboratory use.
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1143-1 ©I EC - 13 -
3 Definitions
The values of a.c. quantities given in this pa rt are r.m.s. values, unless otherwise stated.
For the purpose of this pa rt , the following definitions apply.
3.1 General terms
3.1.1 electrical measuring instrument: A measuring instrument intended to measure an
electrical or non-electrical quantity using electrical means.
3.1.2 analogue display instrument: A measuring instrument intended to present or
display the output information as a continuous function of the measured quantity.
3.1.3 electronic measuring instrument: A measuring instrument intended to measure
an electrical or non-electrical quantity using electronic means.
3.1.4 instrument with electric screen: An instrument shielded by conductive material
from the influence of an electric field of external origin.
3.1.5 accessory: An element, group of elements or device associated with the measur-
ing circuit of a recorder in order to confer specified characteristics on the recorder.
3.1.5.1 interchangeable accessory: An accessory having its own properties and
accuracy, these being independent of those of the recorder with which it may be
associated.
NOTE - An accessory is considered to be interchangeable when its rated characteristics are known and
marked and are sufficient to enable its errors and variations to be determined without using the associated
recorder. For example, a shunt whose adjustment takes into account the input current of the recorder and
which is not negligible and which is known is considered to be interchangeable.
3.1.5.2 accessory of limited interchangeability: An accessory having its own properties
and accuracy, which can be associated only with recorders for which ce rtain characteris-
tics are within specified limits.
3.1.5.3 non-interchangeable accessory: An accessory adjusted to take into account the
electrical characteristics of a specific recorder.
3.1.6 shunt: A resistor connected in parallel with a measuring circuit of a recorder.
NOTE - A shunt is generally intended to provide a voltage proportional to the current to be measured.
3.1.7 series resistor (impedance): A resistor (impedance) connected in series with a
measuring circuit of a recorder.
NOTE - A series resistor (impedance) is generally intended to extend the voltage measuring range of a
recorder.
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1143-1 ©IEC -15 -
3.1.8 distortion factor (total harmonic distortion factor of a quantity):
r.m.s. value of the harmonic content
The ratio:
r.m.s. value of the non-sinusoidal quantity
3.1.9 ripple content of quantity
r.m.s. value of the fluctuating component
The ratio:
r.m.s. value of the d.c. component
3.1.10 recorder: A measuring instrument which records on a recording medium infor-
mation corresponding to the values of the measurand.
NOTES
1 Some recorders may incorporate indicating devices.
2 Some recorders may record information corresponding to more than one measurand.
3 Some recorders may also include interchangeable plug-in units. In this case, a recorder may have dif-
ferent specifications depending on the plug-in unit being used.
3.1.11 indirect acting recorder: A recorder in which the recording device is driven by a
motor or other device controlled by the measurand and using electromechanical, electrical
or electronic means.
3.1.12 drum chart recorder: A recorder in which the chart is wrapped as a single turn
around a cylindrical drum which is rotated by the chart driving mechanism.
disc recorder: A recorder in which the chart is a disc which is rotated by the chart
3.1.13
driving mechanism.
3.1.14 strip chart recorder: A recorder in which the chart is a strip driven by the chart
driving mechanism.
3.1.15 pen recorder: A recorder in which the record on the chart is made by a pen
supplied with ink.
3.1.16 stylus recorder: A recorder in which the record on the chart is made by a stylus
requiring no ink.
3.1.17 array recorder: A recorder in which the record is produced by energizing one or
more of a series of fixed elements.
NOTE - For example, these may be heated elements producing dots on thermal sensitive paper.
3.1.18 dotted line recorder: A recorder in which the record comprises a series of suc-
cessive impressions which may be points, numerals, etc.
NOTE - Recorders producing a series of dots which are so close to each other that they appear like a line
and the dotting time is short enough to be negligible, compared with the response time of the recorder, are
treated as continuous line recorders.
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1143-1©IEC - 17 -
3.1.19 continuous line recorder: A recorder in which the record is a continuous line.
3.1.20 single recorder: A recorder having a single recording device.
3.1.21 multiple recorder: A recorder having more than one recording device.
3.1.22 single range recorder: A recorder having only one measuring range.
3.1.23 multi-range recorder: A recorder having more than one measuring range.
3.1.24 single channel recorder: A recorder the internal measuring circuit of which is
intended to be connected to one external measuring circuit.
A recorder which successively connects its internal
3.1.25 multiple channel recorder:
measuring circuit to different external measuring circuits.
3.2 Description of recorders according to their methods of operation
3.2.1 thermocouple recorder: A recorder which is the combination of a recorder sensi-
tive to direct voltage and a thermal converter whereby alternating currents or voltages may
be recorded.
3.2.2 rectifier recorder: A recorder which is the combination of a recorder sensitive to
direct current and a rectifying device whereby alternating currents or voltages may be
recorded.
r.m.s.-responding recorder: A recorder which, over a specified frequency range,
3.2.3
provides a record which is designed to be proportional to the root-mean-square value of
the measurand.
3.3 Construction features of recorders
The part of the electrical circuit internal to the recorder and its
3.3.1 measuring circuit:
accessories, together with the interconnecting leads, if any, which is energized by a
voltage or a current, one or both of these quantities being a prime factor in determining
the record of the measurand (one of these quantities may be the measurand itself).
3.3.1.1 current circuit: A measuring circuit through which flows a current which is the
prime factor in determining the record of the measurand.
NOTE - This current may be the current which is directly involved in the measurement or a proportional
current supplied by an external current transformer or derived from an external shunt.
3.3.1.2 voltage circuit: A measuring circuit to which is applied a voltage which is the
prime factor in determining the record of a measurand.
NOTE - This voltage may be the voltage which is directly involved in the measurement or a proportional
voltage supplied by an external voltage transformer or an external voltage divider or derived by means of
an external series resistor (impedance).
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1143-1 0O IEC - 19 -
3.3.2 external measuring circuit: The part of the electrical circuit external to the
recorder from which the measurand is obtained.
3.3.3 auxiliary circuit: A circuit, other than a measuring circuit, required for the opera-
tion of the recorder.
3.3.3.1 auxiliary supply: An auxiliary circuit which provides electrical energy.
3.3.4 measuring element: The assembly of those parts of a recorder which are acted
upon by a measurand, resulting in a corresponding movement of the moving element.
3.3.5 moving element: The moving part of a measuring element. [lEV 302-06-02]
3.3.6 indicating device: The part of a recorder which displays the values of the
measurand.
3.3.7 recording device: The assembly of parts of a recorder which records the value of
the measurand.
3.3.8 index: The fixed or movable part of a recorder whose position, with reference to
the scale marks, enables a recorded value to be determined.
3.3.9 scale: The series of marks and numerals from which, in conjunction with the index,
the value of the measurand is obtained.
3.3.9.1 scale marks: Marks on the dial for the purpose of dividing it into suitable inter-
vals so that the position of the index may be determined.
3.3.9.2 zero scale mark: The mark on the dial associated with the figure zero.
3.3.9.3 scale division: The distance between any two consecutive scale marks.
3.3.10 scale numbering: The series of numerals associated with the scale marks.
3.3.11 dial: The surface which carries the scale and other marks and symbols.
3.3.12 electrical zero: The equilibrium position which the index will approach when the
measurand is either zero or a set value and the control circuit (if any) is energized.
3.3.12.1 electrical zero adjuster: For a recorder which needs an auxiliary supply, the
mechanism by means of which the recorder may be adjusted so that the electrical zero
coincides with the appropriate scale mark.
3.3.12.2 electrical span adjuster: For a recorder which needs an auxiliary supply, the
mechanism by means of which the recorder may be adjusted so that the lower and/or
upper limits of the measuring range coincide with the appropriate scale mark.
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1143-1 ©I EC - 21 -
chart: A strip or disc with or without preprinted lines and/or figures from which
3.3.13
are obtained the values of the measurand as a function of time, possibly by means of a
reading rule.
3.3.14 chart lines: The series of lines on the chart which enables the record to be
interpreted.
3.3.14.1 chart scale lines: Chart lines by means of which the value of each measurand
is determined.
3.3.14.2 chart time lines: Chart lines for determining the time at which the value of each
measurand occurred.
3.3.15 chart driving mechanism: A mechanism for driving the chart as a function of
time.
3.3.16 recording width: The length of the record (curved or straight) between the
extreme chart scale lines when the chart driving mechanism is stationary.
3.4 Characteristic features of recorders
3.4.1 The length of the line (curved or straight) which passes through the
scale length:
centres of all the shortest scale marks contained between the first and the last scale
marks.
It is expressed in units of length.
NOTE - If a recorder has more than one scale, each scale may have its own scale length. For con-
venience, the scale length of the recorder is taken to be that of the major scale.
3.4.2 span: The algebraic difference between the upper and lower limits of the measur-
ing range.
It is expressed in units of the measurand.
Example measuring range: -10 V . +10 V: span 20 V.
3.4.3 measuring range (effective range): The range defined by two values of the
measurand within which the limits of error of a recorder are specified.
NOTE - A recorder can have several measuring ranges.
3.4.4 overshoot: The difference between the extreme recorded value and the steady
recorded value (expressed in terms of the recorded value corresponding to the span)
when the measurand is suddenly changed from one steady value to another.
3.4.5 response time: The time interval between the instant when a measurand is sub-
jected to a specified sudden change and the instant when the record reaches and remains
within specified limits of its final steady value.
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1143-1 ©IEC - 23 -
3.4.6 frequency response range: The range of frequencies of a sinusoidal measurand
to which the recorder will respond within specified limits relating to amplitude.
band: The range through which the measurand may be varied without pro-
3.4.7 dead
ducing a change in the record.
The part of the
3.4.8 common mode voltage (between measuring circuit and earth):
input voltages, for which the amplitude and either the phase or the polarity are the same,
which exists between each of the input terminals and a reference point.
NOTE - This reference point may be the frame, the measuring earth terminal or an inaccessible point.
3.4.9 series mode voltage/parallel mode current: An unwanted part of the input quan-
tity which is superimposed on the input quantity initiated by the measurand.
NOTES
1 Typical examples of a series mode voltage are induced voltages, an a.c. ripple on a d.c. signal, or
thermopotentials.
2 The parasitic input value for a voltage input is a voltage applied in series with the measurand.
The parasitic input value for a current input is a current applied in parallel with the measurand.
3.5 Characteristic values
3.5.1 nominal value: A value of a quantity indicating the intended use of a recorder.
The characteristics of recorders given by the manufacturer are also nominal values.
3.5.2 rated value: A value of a quantity assigned, generally by a manufacturer, for a set
of specified operating conditions.
3.5.3 fiducial value: A clearly specified value of a quantity to which the errors of a
recorder are referred to in order to specify its accuracy.
NOTE - This value can, for example, be the upper limit of the measuring range, the span or another
clearly stated value.
3.5.4 rated chart speed: The values of the chart speed assigned by the manufacturer.
3.5.5 dotting time: The interval between the production of two consecutive dots.
3.5.6 zero displacement value: For a recorder with zero displacement, the value of the
measurand, expressed as a percentage of the span, which corresponds to the difference
between the indicated or recorded values with and without the zero displacement for the
same value of the measurand.
3.5.7 recorder with zero displacement: A recorder which employs an additional device
to change the position of the zero.
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1143-1 ©IEC - 25 -
3.6 Influence quantities, reference conditions, nominal range of use and preconditioning
influence quantity: A quantity which is not the subject of the measurement but
3.6.1
which influences the value of the record.
For example: humidity, ambient temperature, frequency of a measured voltage.
reference conditions: Conditions of use for a recorder prescribed for performance
3.6.2
testing, or to ensure valid inter comparison of results of measurements.
NOTE - Reference conditions generally specify reference values or reference ranges for the influence
quantities affecting the recorder.
reference value: A specified value of one of a set of reference conditions.
3.6.2.1
A specified range of values of one of a set of reference
3.6.2.2 reference range:
conditions.
3.6.3 nominal range of use: A specified range of values which an influence quantity
may assume without causing a variation exceeding specified limits.
limiting values of an influence quantity: Extreme values which an influence
3.6.4
quantity can assume without the recorder or accessory being damaged or permanently
altered in such a way that it no longer meets the requirements of its accuracy class.
NOTE - The limiting values may depend on the duration of their application.
3.6.5 preconditioning: The action whereby, under reference conditions, a specified
value of the measurand is applied to the measuring circuit prior to carrying out tests or use
of the recorder or accessory.
preliminary adjustments: Adjustments, specified by the manufacturer, that shall
3.6.6
be made before using the recorder so that it will operate with specified accuracy.
3.7 Errors and variations
3.7.1 (Absolute) error: For a recorder, the value obtained by subtracting the (conven-
tional) true value from the recorded value.
For an accessory, the value obtained by subtracting the (conventional) true value from the
rated value.
NOTES
1 Since the true value cannot be obtained by measurement, a value obtained under specified test
conditions and at a specified time is used instead. This value is derived from national measurement stan-
dards or reference measurement standards agreed upon by manufacturer and user.
2 "Absolute error", which has a sign, should not be confused with "absolute value of an error" which is
the modulus of an error.
3 When a recorder is used together with an accessory, the error of such a combination is calculated by
taking the algebraic sum of the errors of the recorder and the accessory.
4 In practice, the error of measurement can only be determined with some uncertainty.
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1143-1 ©IEC - 27 -
The error of a recorder when under reference conditions.
3.7.2 intrinsic error:
3.7.3 variation: The difference between the two records for the same value of the
measurand for a recorder (or the two true values for an accessory) when a single influence
quantity assumes successively two different specified values within the nominal range of use.
3.7.4 fiducial error: The ratio of the absolute error to the fiducial value. [IEV 301-08-08]
3.7.5 error in timekeeping: The value obtained by subtracting the true value of elapsed
time from the recorded value of time.
3.8 Accuracy, accuracy class, class index
The ability of a recorder to provide a record approaching the conven-
3.8.1 accuracy:
tional true value of a measurand and of the elapsed time.
For an accessory, it is the closeness of the rated value to the conventional true value.
NOTE - The accuracy of a recorder is defined by the limits of intrinsic errors and by the limits of
variations.
A group of recorders and/or accessories which meets certain
3.8.2 accuracy class:
metrological requirements intended to keep errors and variations within specified limits.
3.8.3 Class index
3.8.3.1 measuring class index: The number which designates the measuring accuracy
class.
NOTE - Recorders having more than one measuring range may have more than one measuring class
index.
timekeeping class index: The number which designates the timekeeping
3.8.3.2
accuracy class.
NOTE - It is expressed as a percentage of the ratio of the error in timekeeping to the true value of
elapsed time.
4 Description, classification and compliance
4.1 Description
Recorders and/or their non-interchangeable accessories shall be described according to
their principle of operation and/or by their special characteristics as given in clause 3.
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1143-1 © I EC - 29 -
4.2 Classification
Recorders and their non-interchangeable accessories, satisfying this part are classified
according to their accuracy classes related to the measurand and to timekeeping
(see 6.4).
Accuracy class indices shall be selected from a 1 - 1,5 - 2 - 2,5 - 3 - 5 sequence or their
decimal submultiples.
4.3 Compliance with the requirements of this part
Recorders and their accessories shall comply with the relevant requirements of this part
relating to their accuracy classes. The recommended test methods for checking
compliance with the requirements of this pa rt are given in IEC 51-9 and IEC 1143-2.`
4.3.1 If, for the determination of intrinsic errors and variations, preconditioning is
necessary, the manufacturer shall specify the preconditioning period and all other relevant
conditions. The preconditioning period shall not exceed 30 min.
NOTE - The user should be aware that, when preconditioning is specified, the recorder may not comply
with the requirements corresponding to its accuracy class until the preconditioning has been completed.
4.3.2 Recorders shall be adequately packed to ensure that, after transport under normal
conditions, they comply with the requirements of this pa
rt .
5 Refer
...
Questions, Comments and Discussion
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