AS 60068.2.68-2003

1 - AS 60068.2.68-2003 ENVIRONMENTAL TESTING - TESTS-TEST L: DUST AND SAND
4 - PREFACE
5 - CONTENTS
6 - INTRODUCTION
7 - 1 General
7 - 1.1 Scope
7 - 1.2 Description of test L
8 - 2 Normative references
8 - 3 Definitions
8 - 3.1 dust:
8 - 3.2 dust concentration:
8 - 3.3 humidity:
8 - 3.4 hygroscopic:
8 - 3.5 particle size:
9 - 3.6 sand:
9 - 3.7 sieve (square-meshed):
9 - 4 Test La: non-abrasive fine dust
9 - 4.1 Method La1: cyclic air pressure
9 - 4.1.1 Object
9 - 4.1.2 General description
9 - 4.1.3 Description of test apparatus
9 - 4.1.4 Test conditions
11 - 4.1.5 Preconditioning
11 - 4.1.6 Initial measurements
11 - 4.1.7 Testing
11 - 4.1.8 Intermediate measurements
11 - 4.1.9 Recovery
11 - 4.1.10 Cleaning
11 - 4.1.11 Final measurements
11 - 4.1.12 Information to be given in the relevant specification
12 - 4.2 Method La2: constant air pressure
12 - 4.2.1 Object
12 - 4.2.2 General description
12 - 4.2.3 Description of test apparatus
13 - 4.2.4 Test conditions
14 - 4.2.5 Preconditioning
14 - 4.2.6 Initial measurements
14 - 4.2.7 Testing
15 - 4.2.8 Intermediate measurements
15 - 4.2.9 Recovery
15 - 4.2.10 Cleaning
15 - 4.2.11 Final measurements
15 - 4.2.12 Information to be given in the relevant specification
15 - 4.3 Guidance for test La
15 - 4.3.1 Methods of verification of the degree of protection against ingress of dust into electrotechnical products
16 - 4.3.2 Basic philosophy behind test La, non-abrasive fine dust test
18 - 4.3.3 Methods of generating the test conditions
20 - 4.3.4 Test dust
21 - 4.3.5 Severities of the test
22 - 4.3.6 Reproducibility of the test
23 - 4.3.7 Applicability limits of the test
23 - 4.3.8 Interpretation of results
23 - 5 Test Lb: free settling dust
23 - 5.1 Object
24 - 5.2 Method Lb
24 - 5.2.1 General description
24 - 5.2.2 Description of test apparatus
24 - 5.2.3 Test dust
24 - 5.2.4 Severities
24 - 5.2.5 Preconditioning
25 - 5.2.6 Initial measurements
25 - 5.2.7 Testing
25 - 5.2.8 Intermediate measurements
25 - 5.2.9 Recovery
25 - 5.2.10 Final measurements
25 - 5.2.11 Information to be given in the relevant specification
26 - 5.3 Guidance for test Lb
26 - 5.3.1 Methods of simulation
26 - 5.3.2 Properties and effects of dust in sheltered and enclosed locations
27 - 5.3.3 Basic philosophy behind test Lb, free settling dust
28 - 5.3.4 Method of generating the test conditions
30 - 5.3.5 Severities of the test
31 - 5.3.6 Reproducibility of the test
31 - 5.3.7 Applicability limits of the test
31 - 5.3.8 Interpretation of results
32 - 6 Test Lc: blown dust and sand
32 - 6.1 Method Lc1: recirculating chamber
32 - 6.1.1 Object
32 - 6.1.2 General description of the test
32 - 6.1.3 Description of test apparatus
33 - 6.1.4 Test conditions
35 - 6.1.5 Preconditioning
36 - 6.1.6 Initial measurements
36 - 6.1.7 Testing
36 - 6.1.8 Intermediate measurements
36 - 6.1.9 Recovery
36 - 6.1.10 Cleaning
36 - 6.1.11 Final measurements
36 - 6.1.12 Information to be given in the relevant specification
37 - 6.2 Method Lc2: free blowing dust
37 - 6.2.1 Object
37 - 6.2.2 General description of the test
37 - 6.2.3 Description of test apparatus
37 - 6.2.4 Test conditions
38 - 6.2.5 Preconditioning
38 - 6.2.6 Initial measurements
38 - 6.2.7 Testing
39 - 6.2.8 Intermediate measurements
39 - 6.2.9 Recovery
39 - 6.2.10 Cleaning
39 - 6.2.11 Final measurements
39 - 6.2.12 Information to be given in the relevant specification
40 - 6.3 Guidance for test Lc
40 - 6.3.1 Methods of simulation
40 - 6.3.2 Properties and effects of blown dust and sand
40 - 6.3.3 Basic philosophy behind test Lc, blown dust and sand
41 - 6.3.4 Method of generating the test conditions
44 - 6.3.5 Severity of the test
44 - 6.3.6 Reproducibility of the test
44 - 6.3.7 Applicability limits of the test
44 - 6.3.8 Interpretation of results
51 - Annex A - General guidance
51 - A.1 Characteristics of test dust
53 - A.2 Other dusts
53 - A.3 Effect of humidity on test dust
53 - A.4 Effects on electrotechnical products
55 - A.5 Safety precaution
56 - A.6 Test L and IEC 60529 comparison
59 - Annex B - Bibliography

The objective of this Standard is to provide the electrotechnology industry with a complete set of environmental test procedures published as a series under AS 60068 Environmental testing. This Standard is Part 2.68 of that series.

This part of IEC 60068-2 specifies test methods to determine the effects of dust and sand suspended in air, on electrotechnical products. The test methods of this standard are not intended for the testing of air filters. Only method Lc2 is suitable for the simulation of the erosion effects of high velocity (more than 100 m/s) particles.

First published as AS 60068.2.68-2003.