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Q:谁知道LED灯管的thermal fuse？/ z% k( z0 c$ p
A:出德国加的吧
% r- v) f5 z5 X/ WQ:不是 美国
' f% I; g, ~, ?. f# E) mA:瞅瞅看是不是相关的: p- M7 V! X0 H7 T0 O
/ y- l0 x& W, o8 v- G& j QConsider the following parameters for LED driver fuse selection:
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1. Voltage rating — For 110- to 230-V grid-powered LED applications, a 250-Vac-rated fuse is needed. Note that select countries demanding 277- or 347-V capable solutions require a higher-rated fuse. 3 f4 y2 [$ U( A- s6 W- h, c5 r8 ?
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2. Current rating — This is determined by the power output of the driver. Select a fuse rating that is 20% higher than the nominal LED driver current (select 1-A-rated fuse for a driver with 800 mA nominal current). 3 s, @" Q( k" [7 S9 |& {
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3. Interrupting rating — This determines the maximum current that the fuse can safely interrupt during short circuits. - D6 @; n" v8 d+ c5 X- [5 Z
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0 |4 [. n, j1 X. Z# S5 u6 V4. Temperature derating — Fuses at higher temperatures open at lower currents. The fuse current rating (See Fig. 2) must be derated according to the ambient temperature level. During operation, LEDs generate high levels of heat, which must be conducted away from the printed circuit board. Derating is critical for fuses used close to the light source. ( u9 ` y7 Z5 K
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Fig.2: Fuse temperature rating.
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5. Melting integral (I2t) — LED drivers tend to draw larger currents at power-up due to the initial charging from input capacitors, so a fuse with larger melting integral (I2t) capability makes an ideal choice. ' T& v( C+ g+ d% Q' e
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6. Required agency approvals — Depending on the country of the final lighting device installation, applications may require certification from UL or IEC.
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& a8 V) N+ M9 x* z2 a2 r7. Mechanical considerations (size, shape, etc) — LED drivers typically require fuses as small as possible. Chip fuses starting at 0603-size are available for lower-voltage drivers, and for grid-powered drivers, subminiature radial leaded is the popular choice. 7 T9 Q& ]2 M2 ^4 x" K
https://www.electronicproducts.com/Passive_Components/Circuit_Protection/Get_what_you_need_for_LED_driver_protection.aspx
8 M1 G% t" k; h/ k6 h/ A! C4 TQ:好的 谢谢您
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发表于 2020-3-29 12:50:14
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