1 Scope<\/b><\/p>\n
1.1 These requirements cover solid state automatic transfer switches intended for use in ordinary locations to provide for lighting and power only in optional stand-by systems in accordance with Article 702 of the National Electrical Code, ANSI\/NFPA 70.<\/p>\n
1.2 Solid-state transfer switches are not for use as service entrance equipment unless marked as such.<\/p>\n
1.3 These requirements cover transfer switch equipment rated at 6000 A or less and 600 V or less. <\/p>\n
1.4 These requirements cover transfer switches together with their associated control devices including voltage sensing relays, frequency sensing relays, time delay relays, and the like.<\/p>\n
1.5 An automatic transfer switch as covered by these requirements is a device that automatically transfers a common load from a normal supply to an alternate supply in the event of failure of the normal supply, and automatically returns the load to the normal supply when the normal supply is restored.<\/p>\n
An automatic transfer switch is allowed to be provided with a logic control circuit that inhibits automatic operation of the device from either a normal to an alternate supply, or from an alternate to a normal supply when the switch reverts to automatic operation upon loss of power to the load.<\/p>\n
1.6 A non-automatic transfer switch as covered by these requirements is a device, operated manually by a physical action, or electrically by a remote control, for transferring a common load between a normal and alternate supply.<\/p>\n
1.7 A transfer switch may incorporate overcurrent protection for the main power circuits.<\/p>\n
1.8 These requirements cover completely enclosed transfer switches and also open types intended for mounting in other equipment such as switchboards.<\/p>\n
1.9 Transfer switches are rated in amperes and are generally considered to be acceptable for total system transfer, which includes control of motors, electric-discharge lamps, electric-heating loads, and tungsten-filament lamp loads as referred to in 1.10.<\/p>\n
1.10 A transfer switch intended for total system transfer as indicated in 1.9 is considered to be acceptable for the control of tungsten-filament lamp loads not exceeding 30 percent of the switch ampere rating unless the switch has been investigated for a higher percentage of lamp load and marked accordingly.<\/p>\n
1.11 A transfer switch may be limited to use with one or more specific types of load if investigated accordingly and marked as indicated in 47.11.<\/p>\n","protected":false},"excerpt":{"rendered":"
Standard for Solid-State Transfer Switches<\/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 2018-01-19<\/td>\n 83<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":692669,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2680],"product_tag":[],"class_list":{"0":"post-692658","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\/692658","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\/692669"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=692658"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=692658"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=692658"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}