EN 60068-2-18-2017 pdf download.Environmental testing Part 2-18 : Tests – Test R and guidance : Water.
6.2.3 Method Rb 1.2: spray nozzle
6.2.3.1 Test apparatus
The basic requirements for the test apparatus are as follows.
Spray nozzle (also known as hand-held shower)
A spray nozzle with a spray cone of 78D and a moving shield which is able to limit the
upper part of the spray cone to 30° from the horizontal. The shield may be removed as
specified. The spray nozzle shall have a delivery rate of 10 1/mm ± 5 % which necessitates
a water pressure of 50 kPa to 150 kPa (0.5 bar to 1.5 bar) (see Figure D.3).
• Fixture for the specimen
The fixture shall simulate as far as possible the mounting structure to be used in real use of products; for example, for wall-mounted equipment, the fixture shall simulate a wall.
• Support for the specimen
The support for the specimen shall have a base area which is smaller than the base area of the specimen or be suitably perforated.
• Water supply with controls
The water supply shall be capable of delivering, in a stable flow, at least 10 I/mm. The water used for the test shall be fresh tap water of good quality. In order to avoid clogging of the holes, the water shall be filtered and may be demineralized. Details of the characteristics of the water are given in Annex A. During the test, the water temperature shall not differ by more than 5 K from the temperature of the specimen under test. If the water temperature is more than 5 K below the temperature of the specimen, a pressure balance shall be provided for the specimen.
6.2.3.2 Seventies
The specimen surfaces to be sprayed, if not all, shall be specified. The seventies as indicated by the use of the shield or not and the test duration shall be specified in the relevant specification. The seventies shall be selected from those given below.
• Moving shield: in use, removed.
• Test duration, min/m2 test surface, calculated with a tolerance of ±10 % (subject to a minimum duration, mm)
1(5); 3(15); 6(30).
In some cases, the relevant specification may specify a longer duration.
Preconditioning of the specimen and seals shall be carried out if specified in the relevant specification.
6.2.3.4 Initial measurements
The specimen shall be submitted to the visual, dimensional and functional checks specified In the relevant specification. All features of the specimen likely to affect the test result, such as surface treatment, covers or sealing, shall be inspected to ensure that the instructions of the relevant specification have been followed.
6.2.3.5 Testing
The specimen shall be mounted as described in the oscillating tube test procedure (6.2.2.5 type 1 or type 2). The water pressure shall be adjusted to give a delivery rate of 10 (1 t 5 %) 11mm. It shall be kept constant throughout the test. The specified surfaces shall be sprayed for the specified duration and from a distance of (0,4 ± 0.1) m. When the spray nozzle is used as an alternative to the oscillating tube type 2, the moving shield shall be removed and the spray shall be applied at t180 from vertical.
The relevant specification shall state whether the specimen shall be operated during testing and if intermediate measurements shall be made.
Appropriate safety precautions shall be taken when testing in the energized condition.
6.2.3.6 Recovery
Unless otherwise required in the relevant specification, the specimen shall be thoroughly
dried externally by wiping or by applying low-velocity forced air at room temperature.
6.2.3.7 Final measurements
The specimen shall be examined for ingress of water, and submitted to the visual. dimensional and functional checks specified in the relevant specification.
Any ingress of water shall be quantified if possible and reported.
6.2.3.8 Information to be given In the relevant specification
Where this test is included in the relevant specification, the following details shall be given in so far as they are applicable. The relevant specification shall supply Information as required In the subclauses listed below, paying particular attention to the items marked with an asterisk () as this information is always required.EN 60068-2-18-2017 pdf download.