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标题: ul982的clause36为什么会有对240V的电压规定 [打印本页]

作者: macro    时间: 2011-12-23 19:37
标题: ul982的clause36为什么会有对240V的电压规定
不是很明白为什么会在下面提及到240v。美国的电力系统是120v。那这个240v存在的意义为何?


Normal Temperature Test
36.1 General
36.1.1 An appliance, when tested under the conditions of ²Maximum Normal Load² as described in
36.1.11– 36.26.2, shall not attain a temperature at any point high enough to constitute a risk of fire or to damage any materials employed in the appliance, nor shall the appliance show greater temperature rises at certain specified points than those indicated in Table 36.1 when operated at 120 V or 240 V, and inTable 36.2 when operated also at 127 V or 254 V.
作者: jason1031    时间: 2011-12-23 19:37
美国三相电是240V
作者: macro    时间: 2011-12-23 19:37
Note, for some appliances, you will see three prongs from the outlet plug.
But they might not be three-phase power since they are actually single phase
supply with opposite phases. For example, phase a, neutral, and another
phase a out of 180 degrees. in this way, the voltage between those two LIVE
ports are 2 x 120 = 240VAC
作者: q529891012    时间: 2011-12-23 19:37
2007.8.13的修订版 已删去所有条款中的 240V .




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