|
2. “对音频信号,在故障条件下不要超过正常工作条件下的限值”意思是指 音频信号的故障限值依然是交流35V(峰值)或直流60V,而不是 交流70V(峰值)和直流120V;是吗?为什么会这样呢?9 X& J/ l) k4 ~5 O, i' E3 E( i
! m: U) |6 Q5 [& u– for audio signals of PROFESSIONAL APPARATUS, 120 V r.m.s.,
1 W8 _( K6 F( {8 D– for audio signals of other than PROFESSIONAL APPARATUS, 71 V r.m.s.;
) o, I v% x# B* D! I对音频信号的限值是71Vrms或120Vrms,正常和故障情况下一样。
) [% l+ l i5 x, X; rWhen determining whether a part or output TERMINAL contact is HAZARDOUS LIVE according
) R4 z: h# e# W9 fto 9.1.1.1 and 11.1, the apparatus shall be operated with a sinusoidal input test signal of
8 a% b2 C: F! q: t9 O, k1 kHz or where applicable, another frequency corresponding to the geometric mean of the
+ u' S Q. m$ v, S5 E; X5 U n! zupper and lower –3 dB response points of the relevant amplifier part of the apparatus,9 K9 z, F* C. b
sufficient in amplitude for the apparatus to deliver the NON-CLIPPED OUTPUT POWER into its
$ c8 `4 u# z& ~$ c6 P/ ~7 `0 ORATED LOAD IMPEDANCE. Open-circuit output voltage is determined after the load is( |2 }% a5 v. c' i
removed.
9 | c, U0 ?' x' Z$ }$ j原因如上,标准4.2.4提到判断输出端子是否危险带电时,音频设备要输出非削波输出功率而不是正常工作条件下定义的1/8非削波输出功率。因此规定正常和故障情况下音频端子的危险电压限值是相同的。 |
|