本帖最后由 kennykkou 于 2022-2-15 18:53 编辑 * T* ~! i7 I: L- z) Q) H! l# v2 I3 G/ p& S
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丁先生 非常非常谢谢 再确认新版UL507 没错是 91.4 Fan blade brackets 91.4.1 Static load test for ceiling-suspended fan blade brackets 91.4.1.1 A blade bracket to be used on a ceiling-suspended fan shall besubjected to the static load testdescribed in 91.4.1.2. As a result of theload, the bracket shall have no cracks as determined by visualinspection with a4-power magnifying glass. 91.4.1.2 The mounting feet of the blade bracket are to be fixed by a support,vise, or other securingmeans. The bracket is to be oriented as intended foractual use as illustrated in Figure 91.2. After securing the bracket mounting feet, a crossbar is to be secured across the top ofthe two outermost blade mountingholes. The load is to be suspended from the centerof the crossbar for one minute as illustrated in Figure 91.2. The combined weight of the crossbar, load, and means of load suspensionis to be in accordancewith Table 91.1. Exception: Ifthe blade bracket construction is such that it is integral to the motorenclosure and attachedto the overall motor assembly upon shipment, the bladebrackets/motor enclosure can remain attached tothe motor assembly during testing. |