DSH 752 Definition of a flame for glow wire test
http://decisions.iecee.org/icons/ecblank.gif DSH 752
Definition of a flame for glow wire test
11-12
60695-2-11 & 60695-2-12 & 60695-2-13
Standard(s): No. Year
IEC 60695-2-11
IEC 60695-2-12
IEC 60695-2-13
DSH 0752
2009
Category:
VARIOUS - GENERAL
Sub-clauses:
11 - 12
Developed by:
WG4 – WG2
Subject:
Definition of a flame for glow
wire test
Key words:
- Glow wire test
- Flame
- Corona Effect
- Ionized gasses
- Ignition of the sample
Approved at the 47th CTL
Plenary Meeting, year 2010.
Question:
How is the “Corona-Effect” to be interpreted when performing the Glow Wire Test?
Decision:
During the glow wire test (according to the temperature settings required by the standard), the
following phenomena can occur:
1. If a brightly shining flame is observed directly at the test specimen (see picture 1), this is a
clear indication of an ignition. Some materials show a colourless transparent flame
instead of a bright shiny flame. This is considered to be ignition of the test specimen, if the
maximum flaming time allowed by the standard is exceeded.
2. Sometimes, a circular corona can be observed around the tip of the glow wire, see picture
2. This corona consists of ionized gas, predominantly blue in colour and is located in the
immediate vicinity of the glow wire. This phenomenon is not considered to be ignition of
the test specimen, as long as it does not lead to an ignition of the test specimen according
to point 1.
3. Furthermore, ionized gasses can sometimes be noticed along the glow wire (see picture
3). This effect is also not considered to be ignition of the test specimen, as long as it does
not lead to an ignition of the test specimen according to point 1.
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