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20.1.3 PRINTED BOARDS3 K: z. m$ y8 |+ {" Y3 s( U
Base material of PRINTED BOARDS, on which the AVAILABLE POWER at a connection exceeds
) v1 B; l( S7 r3 N15 W operating at a voltage exceeding 50 V up to and including 400 V (peak) a.c. or d.c. under- r* Z# U6 b% N- D3 Q1 C1 _
normal operating conditions, shall be of flammability category V-1 or better according to
9 _, a5 P4 t- U4 I9 }IEC 60695-11-10, unless the PRINTED BOARDS are protected by an enclosure meeting the
5 Q3 X0 u4 Y0 p( l) F5 k( l* mflammability category V-0 according to IEC 60695-11-10, or be made of metal, having openings& r4 Q) p0 C: F3 G7 x* S
only for connecting wires which fill the openings completely.! {) q) _' o# F- O8 b5 u
Base material of PRINTED BOARDS, on which the AVAILABLE POWER at a connection exceeds 15 W
/ y5 f1 @; A( Y* I; A1 i7 B" j0 Moperating at a voltage exceeding 400 V (peak) a.c. or d.c. under normal operating conditions, and
# R# X- v5 t. l2 |5 gbase material of PRINTED BOARDS supporting spark gaps which provide protection against
- P- P* Z2 ^& `7 L9 ?' o$ G) D8 Z* G, ~overvoltages, shall be of flammability category V-0 according to IEC 60695-11-10, unless the
) ?+ k- H y* ]( U2 F9 l6 XPRINTED BOARDS are contained in a metal enclosure, having openings only for connecting wires
0 n# C1 g1 B2 \; _ E: ~( nwhich fill the openings completely.
$ ]& {7 A" z! E3 {Compliance is checked for the smallest thickness of PRINTED BOARD used, in accordance with x( c: B) X8 G, \# A# K6 c
either:1 @2 c d# T% V; e
a) IEC 60695-11-10; or
9 N% Z& H- L3 i6 q2 ]b) with Clause G.1 on specimens of boards as used in the apparatus, but without components.
+ u2 d7 b: F4 M- `8 [$ gThe tests under b) are performed after a preconditioning of 24 h at a temperature of
_3 v# _) B0 l) ~(125 ± 2) oC in an air-circulating oven and a subsequent cooling period of 4 h at room2 t5 k" Y9 i' c0 T
temperature in a desiccator over anhydrous calcium chloride.
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PCB 的要求 |
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