ISO 7240-31:2022

INTERNATIONAL ISO
STANDARD 7240-31
First edition
2022-09
Fire detection and alarm systems —
Part 31:
Resettable line-type heat detectors
Systèmes de détection et d'alarme incendie —
Partie 31: Détecteurs de chaleur en ligne resetable
Reference number
© ISO 2022
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Published in Switzerland
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Contents Page
Foreword .viii
Introduction .ix
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 3
4.1 General . 3
4.1.1 Conformance . 3
4.1.2 Heat response classes . 3
4.2 Individual alarm indication . 5
4.3 Signalling . 5
4.4 Repeatability . 6
4.5 Reproducibility . 6
4.6 Connection of ancillary devices. 6
4.7 Manufacturer's adjustments . 6
4.8 Software . 6
4.8.1 General . 6
4.8.2 Software design . 6
4.8.3 The storage of programs and data . 6
4.9 Sensing element fault . 7
4.10 On-site adjustment of response behaviour . 7
4.11 Maximum ambient temperature test (sensing element) . 7
4.12 Variation in supply parameters . 7
4.13 Low voltage fault. 7
4.14 Fire sensitivity for Class A and ror-only RLTHD . 7
4.15 Static response temperature test . 7
4.16 Response times from typical application temperature for ror-only RLTHD . 8
4.17 Dry heat (operational) sensor control unit . 8
4.18 Dry heat (endurance) for sensor control unit and sensing element . 8
4.19 Cold (operational) for sensing element . 8
4.20 Cold (operational) for sensor control unit . 8
4.21 Damp heat, steady-state (endurance) for sensor control unit and sensing element . 8
4.22 Damp heat, cyclic (operational) for sensing element . 8
4.23 Damp heat, cyclic (operational) for sensor control unit . 8
4.24 Damp heat, steady-state (operational) for sensor control unit . 8
4.25 Damp heat, cyclic (endurance) for sensor control unit and sensing element . 8
4.26 Shock (operational) for sensor control unit . 8
4.27 Impact (operational) for sensor control unit . 9
4.28 Impact (operational) for sensing element . 9
4.29 Vibration, sinusoidal (operational) for sensor control unit . 9
4.30 Vibration, sinusoidal (operational) for sensing element . 9
4.31 Vibration, sinusoidal (endurance) for sensor control unit . 9
4.32 Vibration, sinusoidal (endurance) for sensing element . 9
4.33 Sulfur dioxide (SO ) corrosion (endurance) for sensing element . 9
4.34 Sulfur dioxide (SO ) corrosion (endurance) for sensor control unit . 9
4.35 Electromagnetic immunity . 9
5 Test methods . 9
5.1 General . 9
5.1.1 Atmospheric conditions for tests. 9
5.1.2 Operating conditions for tests. 10
5.1.3 Mounting arrangements . 10
5.1.4 Tolerances . 10
iii
5.1.5 Procedure for measurement of response time . 10
5.1.6 Provision for tests . 11
5.1.7 Test schedule . 12
5.2 Individual alarm indication . 14
5.3 Signalling . 14
5.4 Repeatability . 14
5.4.1 Object of the test . 14
5.4.2 Test procedure. 14
5.4.3 Requirements . 15
5.5 Reproducibility . .15
5.5.1 Object of the test . 15
5.5.2 Test procedure. 15
5.5.3 Requirements .15
5.6 Connection of ancillary devices. 15
5.7 Manufacturer's adjustments .15
5.8 Requirements for software-controlled detectors . 15
5.9 Sensing element fault . 15
5.9.1 Object of the test . 15
5.9.2 Sensing element operational continuity . 16
5.9.3 Requirements . 16
5.10 On-site adjustment of response behaviour . 16
5.11 Maximum ambient temperature test (sensing element) . 16
5.11.1 Object of the test . 16
5.11.2 Mounting of the sensing element . 16
5.11.3 Test procedure. 16
5.11.4 Requirements .
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