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49 Component Power Measurement Test
, N4 m! ]8 @" ]; R D( d* t; S49.1 To determine if a component or a circuit of a seasonal lighting product is capable of delivering 15 A, ?& X h; z
watts of power for one minute (see 48.1, Exception No. 1(c)), the component shall be tested as described1 B: v6 u+ m/ Q: r
in 49.2 – 49.4.$ x' Z+ r% I* ]# v3 q' v
49.2 The unit is to be connected to a 60 Hz, 120 V supply source. One component or circuit of the unit O, Z. l% y$ u" `, U
is to be connected to a wattmeter and an adjustable external load resistor as illustrated in Figure 49.1.
g8 Q& x7 z6 mThe external load resistor is to be set for its maximum resistance. A closed shorting switch is to be0 ^% M9 G: x- Q& I
connected across the unit’s protective device, such as a fuse, and the resistor is then to be adjusted to. f; _0 m, t1 C$ B
cause a power dissipation of exactly 15 watts as indicated by the meter. The shorting switch across the5 ^/ I" c% z- |" ~2 {* z
protective device is then to be opened and the time required for the protective device to open is to be
4 i$ b( n" b! O' k" H- [recorded.. W q H8 A# d* U/ M7 h# s8 j
49.3 During the test, the supply circuit is to be protected by a 20 A time delay fuse, with characteristics2 @; a S1 ~% N
such that the fuse will not open in less than 12 seconds when carrying 40 A.9 \/ S+ O7 t; V* V$ `
49.4 The point of measurement of the circuit (see Figure 49.1) is not considered capable of delivering 15- i( o# o V( }. n
watts for one minute if:
* L8 X% `, M& h- A; O# aa) The protective device of the unit opens in less than 60 seconds,
l+ b/ o3 V3 o# ?& nb) A circuit component opens in less than one minute, or( I, Y! F) _* Z) h2 s/ @( p
c) The current is inherently limited by the circuit. |
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