類(lèi)型3S -- 防塵，防雨和防雹(冰) -- 室外
　　Type 3S—Dust-tight, Raintight and Sleet (Ice) Proof—Outdoor
　　類(lèi)型3S外殼適用于室外應(yīng)用，保護(hù)殼內(nèi)設(shè)備不受風(fēng)塵和水的侵蝕，并在外殼覆蓋外層冰或雹的情況下，殼內(nèi)設(shè)備仍然能夠運(yùn)行。這些外殼并無(wú)法保護(hù)殼內(nèi)設(shè)備免受由于內(nèi)部結(jié)冰導(dǎo)致的故障。如果有這種要求，則應(yīng)該咨詢(xún)儀器制造商。
　　Type 3S enclosures are intended for use outdoors to protect the enclosed equipment against windblown dust and water and to provide for its operation when the enclosure is covered by external ice or sleet. These enclosures do not protect the enclosed equipment against malfunction resulting from internal icing; where this is a requirement, the apparatus manufacturer should be consulted.

　　類(lèi)型4 -- 防水和防塵 -- 室內(nèi)
　　Type 4—Watertight and Dust-Tight—Indoor
　　類(lèi)型4外殼適用于室內(nèi)，用來(lái)保護(hù)殼內(nèi)設(shè)備不受?chē)姙⑺那治g，滲水，水瀑或軟管道流出的水，以及嚴(yán)重的外部凝結(jié)水的頁(yè)面。
　　Type 4 enclosures are intended for use indoors to protect the enclosed equipment against splashing water, seepage of water, falling or hose directed water, and severe external condensation.

　　類(lèi)型6 -- 可浸入水中，防水，防塵和防雹(冰)，室內(nèi)和室外
　　Type 6—Submersible, Watertight, Dust-Tight and Sleet (Ice) Resistant Indoor and Outdoor
　　類(lèi)型6外殼適用于偶爾會(huì)出現(xiàn)浸水情況的室內(nèi)和室外應(yīng)用。這種外殼應(yīng)該保護(hù)殼內(nèi)設(shè)備不受6英尺靜水壓持續(xù)30分鐘的侵蝕，不受灰塵、無(wú)腐蝕性液體的噴灑或外部凝結(jié)，水瀑或軟管流出的水，棉花和滲水的侵蝕。
　　Type 6 enclosures are intended for use indoors and out-doors where occasional submersion is encountered. They shall protect the enclosed equipment against a static head of water of six (6) feet for thirty (30) minutes, dust, splashing or external condensation of noncorrosive liquids, falling or hose directed water, lint and seepage. They are not sleet (ice) proof.

　　類(lèi)型7，類(lèi)別1，組A, B, C, 和D空氣開(kāi)關(guān)設(shè)備 -- 室內(nèi)
　　Type 7, Class 1, Groups A, B, C, & D Air-Break Equipment—Indoor
　　類(lèi)型7外殼適用于室內(nèi)應(yīng)用，在此環(huán)境和位置符合《美國(guó)電氣規(guī)程》中類(lèi)別1，組A, B, C, 和D的定義。字母A, B, C, 或D表示在危險(xiǎn)區(qū)域內(nèi)的氣體或蒸汽環(huán)境，作為后綴加以指明。正如《美國(guó)電氣規(guī)程》中的定義，“類(lèi)型7”提供完整的NEMA標(biāo)志符號(hào)，分別符合類(lèi)別1，組A, B, C, 或D。
　　Type 7 enclosures are intended for use indoors in the atmospheres and locations defined as Class I and Groups A, B, C, and D in the National Electrical Code. The letters A, B, C, or D which indicate the gas or vapor atmospheres in the hazardous location appear as a suffix to the designation, “Type 7” to give the complete NEMA designation and correspond to Class 1, Group A, B, C, or D, respectively, as defined in the National Electrical Code.

　　類(lèi)型9，類(lèi)別11，組E, F, 和G空氣開(kāi)關(guān)設(shè)備 -- 室內(nèi)
　　Type 9, Class 11, Groups E, F, & G Air Break Equipment—Indoor
　　類(lèi)型9外殼適用于室內(nèi)，其環(huán)境符合《美國(guó)電氣規(guī)程》中有關(guān)類(lèi)別11，組E,F, 或G的定義。字母E, F, 或G表示在危險(xiǎn)區(qū)域內(nèi)的灰塵環(huán)境，作為后綴加以標(biāo)明。正如《美國(guó)電氣規(guī)程》的定義，“類(lèi)型9”提供了完整的NEMA標(biāo)志，分別符合類(lèi)別11，組E, F, 或G。這些外殼防止具有量的危險(xiǎn)粉塵的進(jìn)入。
　　Type 9 enclosures are intended for use indoors in the atmospheres defined as Class 11 and Groups E, F, or G in the National Electrical Code. The letters E, F, or G which indicate the dust atmospheres in the hazardous location appear as a suffix to the designation “Type 9” to give the complete NEMA designation and correspond to Class 11, Group E, F, or G, respectively, as defined in the National Electrical Code. These enclosures prevent the ingress of explosive amounts of hazardous dust.

　　危險(xiǎn)環(huán)境的摘要信息(根據(jù)《美國(guó)電氣規(guī)程》和UL)
　　Summary of Hazardous Atmospheres (Based on National Electrical Code and UL)
　　在NEMA類(lèi)型7和9定義中以加以說(shuō)明。組(用字母標(biāo)明)，標(biāo)記在類(lèi)性和類(lèi)別之后，表示危險(xiǎn)區(qū)域內(nèi)的氣體或蒸汽環(huán)境。
　　As explained in the definitions of the NEMA Types 7 and 9. The groups (indicated by letters), which follow the type class, indicate the gas or vapor atmospheres within the hazardous locations.
　　下列表格列出這些組包括的典型環(huán)境。
　　The following chart is a listing which gives the typical atmospheres covered by these groups.
　　您會(huì)注意到所列的環(huán)境在類(lèi)別內(nèi)包括“子類(lèi)別1或2”。“子類(lèi)別”清楚的表明所在區(qū)域是“通常是危險(xiǎn)的”或是“異常時(shí)是危險(xiǎn)的”。
　　You will note that this list also includes a “Division 1 or 2” in addition to the class. The “Division” simply indicates if the area in question is considered “Normally Hazardous” or “Not Normally Hazardous.”

1. 子類(lèi)別1區(qū)域，通常是危險(xiǎn)的。
   A Division 1 area, is or might be hazardous under normal conditions.
2. 子類(lèi)別2區(qū)域，異常時(shí)是危險(xiǎn)的。
   A Division 2 area, might become hazardous should an unusual condition arise.