ISO 24477:2025

Vacuum technology — Vacuum gauges — Specifications, calibration and measurement uncertainties for spinning rotor gauges

This document defines terms related to spinning rotor gauges (SRGs)[2]-[4], specifies required parameters for SRGs, details the SRG calibration procedure and describes which measurement uncertainties to consider when operating these gauges. This document is applicable to pressure up to 2 Pa.

Technique du vide — Manomètres à vide — Spécifications, étalonnage et incertitudes de mesure pour manomètres à rotor

General Information

• Status: Published
• Publication Date: 11-Mar-2025
• ICS: 23.160 - Vacuum technology
• Technical Committee: ISO/TC 112 - Vacuum technology
• Drafting Committee: ISO/TC 112 - Vacuum technology
• Current Stage: 6060 - International Standard published
• Start Date: 12-Mar-2025
• Due Date: 12-Mar-2025
• Completion Date: 12-Mar-2025

Relations

• Revises: ISO 24477:2022 - Vacuum technology — Vacuum gauges — Specifications, calibration and measurement uncertainties for spinning rotor gauges
• Effective Date: 02-Sep-2023

Standards Content (Sample)

International
Standard
ISO 24477
Second edition
Vacuum technology — Vacuum
2025-03
gauges — Specifications, calibration
and measurement uncertainties for
spinning rotor gauges
Technique du vide — Manomètres à vide — Spécifications,
étalonnage et incertitudes de mesure pour manomètres à rotor
Reference number
© ISO 2025
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Terms related to components . .2
3.2 Terms related to physical parameters .2
4 Symbols and abbreviated terms. 4
5 Principle of a spinning rotor gauge . . 4
6 Specifications for spinning rotor gauge . 5
6.1 Diameter and density of rotor .5
6.2 Materials of rotor and thimble .5
6.3 Connecting flange of thimble .6
6.4 Leak rate of thimble with flange .6
6.5 Suspension head positioning .6
6.6 Limits of rotor frequency .6
6.7 Warm-up period .6
6.8 Baking temperature .6
6.9 Measurement range .6
6.10 Sampling time .6
6.11 Internal volume .6
6.12 Interface and pin connections of controller .6
6.13 Dimensions and weights of suspension head and controller .6
6.14 Display and signal output .6
6.15 Nominal operating (environment) conditions.7
6.16 Storage and transportation conditions .7
6.17 Input power and electrical requirements .7
6.18 Number of display digits .7
7 Additional (optional) specifications for spinning rotor gauge . 7
7.1 Long-term instability .7
7.2 Expected measurement uncertainty .7
7.3 Compatibility between a suspension head and a rotor .7
7.4 Inspection record and calibration certificate .7
7.5 Allowed vibration level .7
7.6 Cable length .8
7.7 Photograph . .8
8 Calibration . 8
8.1 Parameters to be calibrated .8
8.2 Calibration procedures .8
8.2.1 General .8
8.2.2 Calibration method A for σ . . .9
eff,0
8.2.3 Calibration method B for σ .9
eff,0
8.3 Calibration uncertainty .10
8.4 Calibration certificate .10
9 Measurement uncertainty at use . 10
Bibliography .11

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
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with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
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related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 112, Vacuum technology.
This second edition cancels and replaces the first edition (ISO 24477:2022), which has been technically
revised.
The main changes are as follows:
— 8.2.3 Calibration method B for σ has been technically revised
eff,0
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
This document complements ISO 3567 and ISO 27893 when characterizing, calibrating or using spinning
rotor gauges (SRGs) as reference gauges.
SRGs are used to measure pressure in the high and medium vacuum. For the dissemination of the pressure
scale and measurement of high and medium vacuum pressures by this gauge, the relevant parameters,
calibration guidelines and uncertainties should be given, which are described in this document.

v
International Standard ISO 24477:2025(en)
Vacuum technology — Vacuum gauges — Specifications,
calibration and measurement uncertainties for spinning
rotor gauges
1 Scope
[2]-[4]
This document defines terms related to spinning rotor gauges (SRGs) , specifies required parameters
for SRGs, details the SRG calibration procedure and describes which measurement uncertainties to consider
when operating these gauges. This document is applicable to pressure up to 2 Pa.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements 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.
ISO 3529-1, Vacuum technology — Vocabulary — Part 1: General terms
ISO 3529-3, Vacuum technology — Vocabulary — Part 3: Total and partial pressure vacuum gauges
ISO 3567, Vacuum gauges — Calibration by direct comparison with a reference gauge
ISO 27893, Vacuum technology — Vacuum gauges — Evaluation of the uncertainties of results of calibrations b
...