Test of non-separable thin sheet material 6 Q1 v' C9 F+ c
2.10.5.2 , k; M g2 D! y% y& L$ B
60950(ed.3) ' @ j3 ]. l8 L: @ Q B
7 U) ?* @. `/ q" |0 V8 b% i4 iQuestion: ( f3 v l+ K: O4 |7 P* X0 l: y- EHow is non-separable thin sheet insulation in wound components tested? 5 I. M: E3 z) W7 K4 ?, c0 e' }Rationale:# N( e; J( ~ W0 A4 S
There are non-separable thin sheet foils on the market and used in wound components,9 q! E0 C1 U3 H9 v8 F
which cannot be tested according to the requirements and test-method in the existing & w7 t- X/ }# C& m- k/ |. E V; wstandard. A proposal was made to TC74-WG6 how this matter can be handled. The 8 y" J1 f* D& F! l* g/ Pproposal is attached. 8 @/ \8 G4 M \7 u" TDecision:3 q+ `, A; j1 U
Use of non-separable thin sheet insulation in wound components U2 S/ x7 y3 n) j
The following proposal shall be used until the new edition is published. 3 f% |9 p# G1 s$ k6 P+ e1. Introduction, G: _8 P# S6 P1 v+ m
This document presents two alternative versions of the test procedure given in IEC ; ]' w! ?( j1 ]! g/ N% J1 E3 u61558-1 for checking the mechanical durability of thin sheet materials.9 o" R$ X: b- U% ?, z, _
Test method X adapts the published procedure to the conventions and practices used in 3 Z: C% `1 d$ h! `1 N1 O5 mIEC 60950. In Method X, the metal foil is secured to the sample prior to the test. - V, d1 g$ G H; fTest method Y is the slightly different procedure observed on a video presentation, 5 j9 g3 S( V: ]5 b Fwhereby the metal foil is only added to the test assembly after the sample has been* Q8 Z: j: ]3 j6 F# h$ A
stressed by rotating it in the test fixture.9 w6 m8 C' b8 ?5 Q
Test method Y appears to be the more practical method, and is evidently how the test is9 p `8 \( @* u p2 x" Q- N0 h. i
carried out in at least one test laboratory. The two methods should give the same results. % @9 d! n7 l; e- ]5 B2. Proposal 8 d; ]# m2 _* V' B: ~' rChange the title of 2.10.5.2 to the following:: v( T* D, I+ i @
2.10.5.2 Separable thin-sheet material * \; R8 w) a: f- ^3 jModify the first paragraph of 2.10.5.2 as follows:% J$ e" Y% B6 m$ m8 j: `! m6 @
Insulation in separable thin sheet materials, and in two layers of non-separable thin sheet g1 k- l# E. }! Tmaterials, is permitted, ….3 C& x2 v# L% Y# K* Q
Add a new sub-clause 2.10.5.X or 2.10.5.Y. $ J& Y9 ~; T5 Y1 }) Y. x: z% G# p" [Test Method X; N8 `2 D/ S% |5 K- O0 s, [
2.10.5.X Non-separable thin sheet material - ]; x; I4 e; s7 B* Y/ w) TInsulation in three or more layers of non-separable thin-sheet materials is permitted for use within @5 t2 v( d5 H+ B$ c
the equipment ENCLOSURE, and shall not be subject to handling or abrasion during servicing. It4 T: g' w/ x; K0 P
shall have adequate mechanical strength. ) Q: `, B4 O# P7 F( }. J& ~& w xNOTE - The purpose of the tests in 2.10.5.X is to reveal defects that are hidden in inner layers of insulation,. S, K$ y* K. t& V' e. w
so there is no test for insulation in two layers. For insulation in two layers of non-separable thin-sheet . l! m" f1 E% v. q7 _: k/ \materials, see 2.10.5.2) b% `6 k# [1 {9 j, x% I% c
There is no requirement regarding distances through insulation, nor for all layers of insulation to be ) D+ d' w- ` I& @6 ^$ y8 z! @5 rof the same material.0 ], _8 s2 U, T1 ?1 z5 a
Compliance is checked by inspection and by the following test:# {: Z! E3 U* c1 B- o1 c; v
Three test samples of thin sheet material are used, each approximately 70 mm wide. . E0 U) `: l- ]' B$ k# n; }0 l0 ]/ LOne sample is fixed to the mandrel of the test fixture as shown in figure 5X." [* y* d. o* L" T _8 I
A sheet of aluminium or copper foil, 0,035 mm ± 0,005 mm thick, approximately 30 mm wide and at9 I4 e) k; w8 U' }
least 100 mm long, is fixed to the surface of the sample. The foil is positioned so that its edges are! i5 V1 d( J" \
approximately 20 mm from the edges of the sample (see figure 5Xd) and so that when the7 v; w' v; G; C6 _: [; X9 K
mandrel is in its final position, the foil overlaps the free end of the sample by at least 10 mm (see( }9 F2 o% w) Z4 r( F# K; ^
figure 5Xc). The foil is tightened by a pull of approximately 1 N, using an appropriate clamping6 `; m6 ]0 F2 G- S+ K, e8 p, H
device., `# b& I9 g' M H
A pull of 150 N is applied to the free end of the sample, using an appropriate clamping device. The , F( m2 U4 K4 [) K3 Z; ]" K. ?mandrel is twice rotated forwards and backwards by 230°, and then forwards to the final position. ( I8 B1 w6 z7 e( \5 cWhile the mandrel is in its final position, and within the 60 s following the final positioning, an & a8 R' m* L/ [, P- qelectric strength test is applied between the mandrel and the metal foil in accordance with 5.2.2, : G R$ @- ~( q3 r! x4 `using a test voltage of 1,5 times the value specified in table 5B. % { k% L8 M& qThe test is repeated with the other two samples ) v$ j: T$ n* J* a, PIf a sample breaks at the clamping device during rotation, the test is repeated on a fresh sample. If , U/ c) D( i. W( B1 a. U6 Fone or more samples breaks at any other place, the test has failed. 1 v- @4 u1 |9 S/ w/ v* [ Q( p4 k............................ 2 ?- Y! Y5 Y' | B. RAdd new Figure 5X (adapted from Figure 6 of IEC 61558-1)6 D5 [1 M, c/ M6 r
Figure 5Xa is as figure 6a of IEC 61558-1, modified as follows: 9 f/ s( C x0 c9 WReplace "3 x R = 0,5 ± 0,02" by "R = 0,5 ± 0,02 (typ)" 4 |. H f% R, M/ Y& ]7 BReplace "Material: steel nickel plated or brass" by "Material: metal" % x; f; O1 O7 q6 c5 s5 e' VFigure 5Xd is the same as figure 6c of IEC 61558-1 * D, P. z6 S" U! W( qTest Method Y . M+ O5 F$ Q9 L! o2.10.5.Y Non-separable thin sheet material 8 b9 ^8 V) y0 E3 u3 b) p$ P) n& mInsulation in three or more layers of non-separable thin-sheet materials is permitted for use within4 K6 e$ L5 A, {3 q
the equipment ENCLOSURE, and shall not be subject to handling or abrasion during servicing. It, m2 Q4 E' [. P6 v! H: e3 n( m
shall have adequate mechanical strength. * `- v X- ]8 `NOTE - The purpose of the tests in 2.10.5.y is to reveal defects that are hidden in inner layers of insulation,7 {5 C/ {4 k5 d) K
so there is no test for insulation in two layers. For insulation in two layers of non-separable thin-sheet / A4 c, N7 U7 S3 i' g9 A4 ymaterials, see 2.10.5.2 # L6 C# w H6 I' p1 ZThere is no requirement regarding distances through insulation, nor for all layers of insulation to be$ S" N. c& F ?5 |8 a
of the same material.+ ~9 C8 E$ G0 a( j" X: R
Compliance is checked by inspection and by the following test:) |, l' N+ Z7 R. z
Three test samples of thin sheet material are used, each approximately 70 mm wide. 2 q$ u X' g* H" lOne sample is fixed to the mandrel of the test fixture as shown in figure 5Y.7 S+ b! T8 i. I1 W
A pull of 150 N is applied to the free end of the sample, using an appropriate clamping device. The: ]2 B$ U' [6 o# t2 `; S
mandrel is twice rotated forwards and backwards by 230°, and then forwards to the final position. / ~7 l9 k0 c% c% a5 c0 DA sheet of aluminium or copper foil, 0,035 mm ± 0,005 mm thick, approximately 30 mm wide and at ) y9 _8 F! m) s8 Y- ^; jleast 200 mm long, is placed across is the surface of the sample, hanging down on each side of1 F! m# G0 H4 B9 O9 w" A v# ^
the mandrel. The foil is tightened by a pull of approximately 1 N at each end, using appropriate% W! n: i; N$ I: L5 l7 J. n
clamping devices.. The foil is positioned so that its edges are approximately 20 mm from the edges 9 y; C) ^$ o9 H J/ V& I9 q$ X+ Hof the sample (see figure 5Yd).( {3 P" _( y j; N9 h% {
While the mandrel is in its final position, and within the 60 s following the final positioning, an % a+ N! A2 y( w/ R5 z) Relectric strength test is applied between the mandrel and the metal foil in accordance with 5.2.2,1 `" w. a) n$ w1 j) `
using a test voltage of 1,5 times the value specified in table 5B. ; ~# l3 [2 Q# L$ Q3 ]The test is repeated with the other two samples9 _ g8 b! u- d) G V
If a sample breaks at the clamping device during rotation, the test is repeated on a fresh sample. If ) t* b3 ?2 q H! b# i8 P9 Kone or more samples breaks at any other place, the test has failed.4 t6 j7 r; M% @- m4 [! i
.............................../ v( p& m4 i, U7 s
Add new Figure 5Y (adapted from Figure 6 of IEC 61558-1) 6 S- }4 s: b& b5 q! bFigure 5Ya is as figure 6a of IEC 61558-1, modified as follows:/ a. k, v( x; F) E
Replace "3xR = 0,5 ± 0,02" by "R = 0,5 ± 0,02 (typ)" # T, d: ~: n1 e- f8 @Replace "Material : steel nickel plated or brass" by "Material: metal" / W7 j" P& [ ?Figure 5Yd is the same as figure 6c of IEC 61558-1 # G4 \5 o! }- b ~$ v/ M, h F9 E
[attach]77168[/attach] , E1 w, z8 \& N6 ~. X" F 4 t: { g. e+ W: J$ P b8 S0 R 6 K4 \$ F) a5 q V! y8 f: U
DSH 392% Y, x8 O. e& [: `" E, {* m