|
12.7 Thermal test in regard to fault conditions in lamp controlgear or electronic" K1 N. f9 A& ~! Z' t% D/ G& U
devices in plastic luminaires
, ?6 z7 A' A w6 F$ u% l. n9 wThe test applies only to luminaires with a thermoplastic housing not fitted with an extra
- [" |% Y: w/ v7 qmechanical temperature-independent device as per 4.15.2.: z. _- T8 g( Y* |( X* R6 @7 H
8 ^/ j8 X" ]' R# w12.7.1 Test for luminaires without temperature sensing controls1 u& p( H9 |1 w0 o" J. ^0 E
The luminaire shall be tested under the conditions specified in items a), c), e), f), h) and l) of, h8 l- B+ c$ Y$ t8 @* x/ }8 l
12.4.1. In addition, the following also applies.; s4 I$ v! N8 z9 P* t3 d$ A1 l
20 % of the lamp circuits in the luminaire, and not less than one lamp circuit, shall be
# Z& M+ W* f- [1 u& l) Ssubjected to abnormal conditions (see item a) of 12.5.1).2 J' x! c& h1 W1 r
The circuits which have the most thermal influence on the fixation point and exposed parts4 U& r8 f" x7 T! g! D. ]& T
shall be chosen and other lamp circuits shall be operated at rated voltage under normal5 p" s" S$ V7 V& k* o: y+ f
conditions.
) j" C5 n# W0 pThe circuits subjected to abnormal conditions shall be operated at 1,1 times (the rated voltage8 |/ G; J$ D+ S. ?4 R5 S5 h" e' m) M
or the maximum of the rated voltage range). When conditions are stable, the highest winding1 H: H5 x% ^* n' a; \! @
temperature and highest temperature of fixing points and most thermally influenced exposed
) r* Y' A& _# b1 ?, r2 P6 Z( }) Z- Gparts shall be measured. It is not necessary to measure the temperature of small wound6 {; D+ |% F) x3 y2 A6 d
devices that are incorporated within electronic circuits.' s. B4 J& ]' Q. f/ T7 U
Compliance0 ]" v& w$ R7 z* N
The values of the ambient temperature and the temperature measured at 1,1 times (the rated
7 L: V7 k x |) P6 T( Jvoltage or the maximum of the voltage range) are used for the linear regression formula in
$ F$ k& `8 u+ N! a* G" @! f4 ]calculating the temperature of fixing points and other exposed parts in relation to a
) C3 H+ S- A5 _! g% R+ jballast/transformer winding temperature of 350 °C. The calculated value shall not exceed the
& c! L* }7 C2 s2 Qtemperature of the deflection under load of the material in accordance with method A as+ x9 B2 l, Y2 n" s; A+ T0 D
defined in ISO 75 (1987), Plastics and ebonite – Determination of temperature of deflection
: Y* A& V5 S9 \! J- {under load.! l% o, z! Q3 S
12.7.2 Test for luminaires with temperature sensing controls internal/external to the
! O# a% a) ]1 e3 nballast or transformer" d! u- s: g+ D: ? w
The luminaires shall be set up for this test as described in the first three paragraphs of 12.7.1.
3 R& }* Y( t% z3 _, b
; v1 o' @& D6 q5 m; c% Z) l6 vThe circuits subjected to abnormal conditions shall be operated with a slowly and steadily
$ s% y. i; @( u+ y" g: j. ~3 W0 ], Jincreasing current through the windings until the temperature sensing control operates.+ Z a. @" G$ o; [
Time intervals and increments in current shall be such that thermal equilibrium between2 B4 m# ]# h9 W8 L) i0 @) ~
winding temperatures and temperature of fixing points and most thermally influenced exposed
$ _+ `8 o7 t5 E5 P0 `4 z+ D8 fparts is achieved as far as is practicable. During the test, the highest temperature of the spots9 p1 I& S( ~0 o$ @) z3 ]% Z7 N
tested shall be continuously measured.2 y8 z. l- T! W1 |
For luminaires fitted out with manual-reset thermal cut-outs, the test shall be repeated six
- C8 \. A7 t7 S& |. N" utimes allowing 30 min intervals between tests. At the end of each 30 min interval, the cut-out6 E5 |3 w Z( M$ B
shall be reset.
9 V2 @$ S: q2 lFor luminaires fitted out with auto-reset thermal cut-outs, the tests shall be continued until a9 a* _1 D5 g0 B" e) ^2 ?% k8 D" H+ e
stable temperature is achieved.
( r5 S( n `% b" ]3 P, J( \$ u% GCompliance
: c, Y5 ?% Q4 k/ |& Z9 h* oThe highest temperature of the fixing points and most thermally influenced exposed parts,9 u! m9 h# q0 p% P! J' n% S
shall not exceed the temperature of deflection under load of the material according to the
3 {* `6 X5 p7 j, }& j7 Y3 h$ y9 m1 Cmethod A as defined in ISO 75, at any time during the tests for thermal links, manual-reset
" p6 z' B( h+ Q1 ~# c- x! B3 uthermal cut-outs, and auto-reset thermal cut-outs.
) s5 ~& }% {6 e! C1 o+ ^; DIn applying the requirements of 4.15 and 12.7 the following notes are to be referred to:1 \2 j. |4 `' Y9 p8 B
NOTE 1 - ‘Fixing points’ means both the fixing points of components and the fixing points of a luminaire to the4 d- g% ^. t0 b' t& k7 j
mounting surface.
9 z. ^) Z5 ]+ O/ l8 E5 R1 r9 }- Z5 i' |, W+ Q
NOTE 2 - ‘Exposed part’ means the outer surface of the luminaire enclosure.
% Q) a8 X& L. h% e, {' i4 d$ }/ bNOTE 3 - Measurement of exposed parts is restricted to those parts providing the luminaire/component fixing or: m) m% V# T; s) V$ b
parts providing a protective barrier against accidental contact with live parts, as required by section 8 of this* {; M8 ?( M% L5 x" I" F
standard.
. D7 B: s" R+ iNOTE 4 - The hottest part of the thermoplastic material section requiring test is measured. This may often be on
( n+ u7 `- G/ }1 f# n6 athe internal surface of a luminaire enclosure not the outer surface.1 |! t! @4 P' g- o! k
NOTE 5 - The material temperature limits defined by clause 12.7 are with respect to materials under both
" u: }) e; V) ~% V- t: Nmechanical load and no mechanical load.
5 i/ ~ U7 Q! H& q& }3 {- o9 D$ O% |NOTE 6 - The application of clause 12.7 must be read together with the requirements of sub-clause 4.15. |
|