Test of non-separable thin sheet material3 m! m2 I5 T) ?& Y% E% Z
2.10.5.22 s% U D2 w9 Y* ]/ @% B4 M
60950(ed.3) - Z) R- j4 K; i
0 m3 w$ m/ M0 h, aQuestion: : a5 d* T$ {' ]% rHow is non-separable thin sheet insulation in wound components tested?9 f/ ~# p O) r$ i0 M- m
Rationale: & Q" y0 i1 [' d/ T% {, E) b% ^5 ~There are non-separable thin sheet foils on the market and used in wound components, - P& q# L% W2 m" Q5 p' awhich cannot be tested according to the requirements and test-method in the existing - k, M% W4 K# _2 l' _1 m# @standard. A proposal was made to TC74-WG6 how this matter can be handled. The / }! r$ K' G G% ^6 f |' aproposal is attached. # I, R; D4 n0 E, ]) r' uDecision: - q3 Y2 c" ^" k2 J8 }Use of non-separable thin sheet insulation in wound components7 u( P6 l# O. W: ?& S0 L: l
The following proposal shall be used until the new edition is published. 7 ^+ I2 a: f9 O, ~! q6 J1. Introduction2 q! k# I- y; Y0 |# y' c
This document presents two alternative versions of the test procedure given in IEC, y% B) ^8 M0 } T9 ?7 y+ {! C
61558-1 for checking the mechanical durability of thin sheet materials./ n! ?0 c# Z0 U# T; d
Test method X adapts the published procedure to the conventions and practices used in g* v& k, ^% Z9 z2 fIEC 60950. In Method X, the metal foil is secured to the sample prior to the test. 9 g1 ~3 a0 }# ~9 F. ^3 Z+ c5 `. ETest method Y is the slightly different procedure observed on a video presentation,' g" M2 L0 ~. M+ R0 F3 z& }
whereby the metal foil is only added to the test assembly after the sample has been % N C' g/ h0 h# Tstressed by rotating it in the test fixture.5 K6 x2 a4 r* v( i( W2 i
Test method Y appears to be the more practical method, and is evidently how the test is 0 d6 f @8 ?/ Z: I% jcarried out in at least one test laboratory. The two methods should give the same results.$ u- O% f- z4 o: v
2. Proposal $ o! e7 J& k' F" z8 A& U0 h% p0 ?Change the title of 2.10.5.2 to the following:# w9 `7 J h, C5 T% R
2.10.5.2 Separable thin-sheet material& X3 Z# y1 i4 _! D
Modify the first paragraph of 2.10.5.2 as follows: " a* y D8 w, WInsulation in separable thin sheet materials, and in two layers of non-separable thin sheet 5 M/ O# W5 d' Amaterials, is permitted, …. . S h) ?" H+ T) k6 s; jAdd a new sub-clause 2.10.5.X or 2.10.5.Y. ) ?: v- j5 m3 [Test Method X9 A; {2 k" w+ Z$ X3 q, R! M4 B
2.10.5.X Non-separable thin sheet material' A& i& N: {* C# u2 S
Insulation in three or more layers of non-separable thin-sheet materials is permitted for use within ( x4 ^: y$ f2 g& ^0 ]the equipment ENCLOSURE, and shall not be subject to handling or abrasion during servicing. It ' R3 s* }+ s. F, E/ _3 d7 k8 M' v; Pshall have adequate mechanical strength. + V/ S. ^ O5 {. }& BNOTE - The purpose of the tests in 2.10.5.X is to reveal defects that are hidden in inner layers of insulation,- j0 g% z3 w, m+ g: E. Q
so there is no test for insulation in two layers. For insulation in two layers of non-separable thin-sheet- j$ q* N$ q8 W) ~
materials, see 2.10.5.2" e2 S" ?$ Z1 i$ R
There is no requirement regarding distances through insulation, nor for all layers of insulation to be u5 ]- u* ^ G2 l
of the same material.7 p. \" X0 @7 n% X# t& B
Compliance is checked by inspection and by the following test:) I7 A1 {1 T+ O0 z9 U5 J
Three test samples of thin sheet material are used, each approximately 70 mm wide. $ W/ T/ V' {$ v5 l5 _, hOne sample is fixed to the mandrel of the test fixture as shown in figure 5X./ ^8 A% u; j( C/ G
A sheet of aluminium or copper foil, 0,035 mm ± 0,005 mm thick, approximately 30 mm wide and at8 i+ y8 j3 m4 T8 ?+ C# N# }
least 100 mm long, is fixed to the surface of the sample. The foil is positioned so that its edges are) @" b. Z0 `5 n
approximately 20 mm from the edges of the sample (see figure 5Xd) and so that when the9 \, ?0 n- ~7 d7 V
mandrel is in its final position, the foil overlaps the free end of the sample by at least 10 mm (see4 v) A: p& H" m8 I$ X* x8 F
figure 5Xc). The foil is tightened by a pull of approximately 1 N, using an appropriate clamping/ I4 }& Y/ r" o9 ~
device.$ N& S: U0 c! c# H( Q; n
A pull of 150 N is applied to the free end of the sample, using an appropriate clamping device. The5 _7 d Y! t8 p3 ]3 ~: T
mandrel is twice rotated forwards and backwards by 230°, and then forwards to the final position.8 M$ ~, g2 e. y, j2 K' S7 w2 T/ Z
While the mandrel is in its final position, and within the 60 s following the final positioning, an ; W. {$ Z$ o2 selectric strength test is applied between the mandrel and the metal foil in accordance with 5.2.2,9 C5 I; _* \0 e6 R/ l
using a test voltage of 1,5 times the value specified in table 5B. 0 \) w* T, {: T3 M7 Z3 |The test is repeated with the other two samples / |* ~& P o. V' _0 V; }If a sample breaks at the clamping device during rotation, the test is repeated on a fresh sample. If% w& d- M! s1 T" U& s
one or more samples breaks at any other place, the test has failed.0 `0 d z5 K' i7 O
............................ * H: f( u0 o8 o6 vAdd new Figure 5X (adapted from Figure 6 of IEC 61558-1)0 l- v9 v" ^& r h
Figure 5Xa is as figure 6a of IEC 61558-1, modified as follows:8 S: W% V- x; p I" g
Replace "3 x R = 0,5 ± 0,02" by "R = 0,5 ± 0,02 (typ)"6 K* r( E8 w: D% L" j g
Replace "Material: steel nickel plated or brass" by "Material: metal"% E2 u6 @3 h5 T+ ?8 I
Figure 5Xd is the same as figure 6c of IEC 61558-1 0 e% V6 ~" f# R, g( { P! N6 cTest Method Y4 }4 y7 O- G6 e) ?* J( S3 [
2.10.5.Y Non-separable thin sheet material % }0 m* s2 v& _% E/ BInsulation in three or more layers of non-separable thin-sheet materials is permitted for use within# S2 ?- y! P5 s9 _6 L' r
the equipment ENCLOSURE, and shall not be subject to handling or abrasion during servicing. It 9 l P1 R6 Y! W5 }) W" nshall have adequate mechanical strength. * S1 t" \* n# B! U2 |. qNOTE - The purpose of the tests in 2.10.5.y is to reveal defects that are hidden in inner layers of insulation, 3 f5 ]5 e5 I( O+ oso there is no test for insulation in two layers. For insulation in two layers of non-separable thin-sheet " o% E# `7 b$ l. ~4 mmaterials, see 2.10.5.2 6 \3 g0 `: j9 m1 w7 CThere is no requirement regarding distances through insulation, nor for all layers of insulation to be8 F7 d( h/ Y( \( q1 J0 l; Q! {! {
of the same material. & S7 a) d! z7 J) r, @, X }Compliance is checked by inspection and by the following test:1 o; }9 ?7 B& R
Three test samples of thin sheet material are used, each approximately 70 mm wide.; ^4 y6 p. n) e4 S
One sample is fixed to the mandrel of the test fixture as shown in figure 5Y.# F1 j9 U: E! t' j4 j
A pull of 150 N is applied to the free end of the sample, using an appropriate clamping device. The 5 ?+ r U9 ]! e/ Vmandrel is twice rotated forwards and backwards by 230°, and then forwards to the final position.. n/ m0 y% @4 `+ M
A sheet of aluminium or copper foil, 0,035 mm ± 0,005 mm thick, approximately 30 mm wide and at# m# W' y, p! d3 g' M
least 200 mm long, is placed across is the surface of the sample, hanging down on each side of5 k4 D3 W; F. w# F# P3 h+ ^
the mandrel. The foil is tightened by a pull of approximately 1 N at each end, using appropriate ! U$ ~: L$ Q; G9 Q8 w8 oclamping devices.. The foil is positioned so that its edges are approximately 20 mm from the edges$ x" j4 |/ ^4 j) E* q- C9 D( M
of the sample (see figure 5Yd).9 x( Q: H8 o& L2 c* c, T
While the mandrel is in its final position, and within the 60 s following the final positioning, an4 z! u! j4 I6 v |3 F
electric strength test is applied between the mandrel and the metal foil in accordance with 5.2.2, ( W" \# F9 G3 |9 S( G4 yusing a test voltage of 1,5 times the value specified in table 5B.3 |( e, S$ E: S9 O
The test is repeated with the other two samples& |+ i1 ]- x, D& N s5 C% E
If a sample breaks at the clamping device during rotation, the test is repeated on a fresh sample. If . x5 B" f* ?( U. F' t! X4 gone or more samples breaks at any other place, the test has failed. % E& r- F3 Q; h- ^9 U0 ?$ s...............................( ? C# {0 t) T. @
Add new Figure 5Y (adapted from Figure 6 of IEC 61558-1)( M0 s+ L) ^8 n
Figure 5Ya is as figure 6a of IEC 61558-1, modified as follows:% t6 F. ~! q1 P' S- B( t" Q: Q( l
Replace "3xR = 0,5 ± 0,02" by "R = 0,5 ± 0,02 (typ)" % E7 H/ W. J2 Q% E: ?# R6 UReplace "Material : steel nickel plated or brass" by "Material: metal" / @; B1 l5 q5 E0 \: aFigure 5Yd is the same as figure 6c of IEC 61558-10 m3 f; N6 L* X/ @
& ?; v6 R. I P G) {[attach]77168[/attach]4 B+ }% a; f% h; W- I
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