1 Scope<\/b><\/p>\n
\n
1.1 As noted in Low Voltage Transformers \u2013 Part 1: General Requirements, UL 5085-1<\/b>, or CSA C22.2 No. 66.1, Low Voltage Transformers \u2013 Part 1: General Requirements, the requirements in Part 3 cover Class 2 transformers for use with Class 2 circuits in accordance with the National Electrical Code, ANSI\/NFPA 70, or the Canadian Electrical Code, Part I, CSA C22.1. They are intended for connection to essentially sinusoidal supply sources.<\/p>\n<\/p>\n
Advisory Note<\/i> <\/p>\n
: For transformers intended for use in the United States, these requirements also cover Class 3 transformers for use with Class 3 circuits in accordance with the National Electrical Code, ANSI\/NFPA 70, unless otherwise specified in this standard. See Annex D for Class 3 requirements.<\/i> <\/p>\n<\/p>\n
\n
1.3 In addition to the items specified in Clause 1.3 of Part 1, the requirements of Part 3 do not cover:<\/p>\n
a)\u00a0Power supplies (a transformer provided with a rectifier is considered a power supply);<\/p>\n<\/li>\n
b)\u00a0Toy transformers;<\/p>\n<\/li>\n
c)\u00a0Cord and plug connected transformers other than Class 3;<\/p>\n<\/li>\n
d)\u00a0Direct plug-in transformers;<\/p>\n<\/li>\n
e)\u00a0Transformers intended for use in audio, radio, or television type appliances; or<\/p>\n<\/li>\n
f)\u00a0 Other special types of transformers covered in requirements for other electrical devices or appliances.<\/p>\n<\/li>\n<\/ol>\n
Advisory Note:<\/i> <\/p>\n
The requirements of Part 3 do not cover transformers intended for use in the United States having a nominal primary rating of more than 600 V and transformers having overvoltage taps rated over 660 V.<\/i> <\/p>\n<\/p>\n
\n
1.7 This part is intended to be used in conjunction with Part 1. The numbering of the clauses in Part 3 corresponds to the numbered clauses in Part 1. The requirements in Part 1 apply unless modified by Part 3.<\/p>\n<\/p>\n
\n
1.8 A Class 2 transformer that includes a separate current-limiting impedance such as a resistor or a positive temperature coefficient device (PTC) is covered by these requirements.<\/p>\n<\/p>\n
\n
1.9 A Class 2 transformer that includes a resonance regulating circuit is covered by these requirements.<\/p><\/p>\n","protected":false},"excerpt":{"rendered":"
Low Voltage Transformers – Part 3: Class 2 and Class 3 Transformers<\/b><\/p>\n\n\n
\n Published By<\/td>\n Publication Date<\/td>\n Number of Pages<\/td>\n<\/tr>\n \n UL<\/b><\/a><\/td>\n 2022-01-28<\/td>\n 41<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":694234,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2680],"product_tag":[],"class_list":{"0":"post-694225","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-ul","8":"first","9":"instock","10":"sold-individually","11":"shipping-taxable","12":"purchasable","13":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/694225","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/694234"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=694225"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=694225"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=694225"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}