{"id":75,"date":"2022-08-14T18:46:04","date_gmt":"2022-08-14T16:46:04","guid":{"rendered":"https:\/\/www.kth.se\/blogs\/emd\/?p=75"},"modified":"2022-08-14T18:47:21","modified_gmt":"2022-08-14T16:47:21","slug":"disassembling-an-induction-machine","status":"publish","type":"post","link":"https:\/\/www.kth.se\/blogs\/emd\/2022\/08\/disassembling-an-induction-machine\/","title":{"rendered":"Disassembling an induction machine"},"content":{"rendered":"

It is always fun to disassemble something without the burden of reassembling it!<\/p>\n

This time an ancient induction machine, MT71B14-4, manufactured by ASEA (The “A” in “ABB”) becomes my victim.<\/p>\n

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This guy. Let’s do it!<\/p>\n

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The nameplate says that this machine is rated as class B according to the IEC standard 34-1-1960. Its rated power is 0.37 kW, rated rotating speed is 1400 rpm, and rated power factor is 0.69.\u00a0 If the “Y-connection” is adopted for the three phase of stator windings, its rated linear voltage is 380 V and rated current is 1.3 A; while if the “Delta-connection” is adopted for the three phase of stator windings, its rated linear voltage is 220V and rated current is 2.3 A.<\/p>\n

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The connection methods of electrical\u00a0 cables for them are illustrated on the backside of its lid.<\/p>\n

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Obviously the “Y-connection” is adopted for the three phase of stator windings.<\/p>\n

The non-drive end has a centrifugal fan which helps cool the machine with forced air convection.<\/p>\n

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The cover with louvers.<\/p>\n

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The cowling which guides the airflow into open channels between fins on the casing.<\/p>\n

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The fan has radial straight shape blades, which makes it able to work in both rotating directions.<\/p>\n

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The endcap, which fixes the position of the bearing and support it.<\/p>\n

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The flange in the drive end, guessed to be used for connecting with the load machine.<\/p>\n

There are 24 slots in total for the stator.<\/p>\n

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Random windings are used for this kind of small size squirrel caged motor.<\/p>\n

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Rotor bars are skewed to improve the starting torque, prevent the magnetic locking between the rotor and the stator.<\/p>\n

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A common ball bearing is used in this machine.<\/p>\n

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There are two washers below a specific bolt at the end ring to balance the weight of the rotor.<\/p>\n

Where are my chainsaws? Now I will cut these endwindings off…<\/p>\n

P.S. Thanks to Jesper Freiberg for the help in the disassembling process.<\/p>\n","protected":false},"excerpt":{"rendered":"

It is always fun to disassemble something without the burden of reassembling it! This time an ancient induction machine, MT71B14-4, manufactured by ASEA (The “A” in “ABB”) becomes my victim. This guy. Let’s do it! The nameplate says that this machine is rated as class B according to the IEC standard 34-1-1960. Its rated power … Continue reading “Disassembling an induction machine”<\/span><\/a><\/p>\n","protected":false},"author":1340,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"categories":[7],"tags":[],"class_list":["post-75","post","type-post","status-publish","format-standard","hentry","category-emd-at-kth"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/posts\/75","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/users\/1340"}],"replies":[{"embeddable":true,"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/comments?post=75"}],"version-history":[{"count":3,"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/posts\/75\/revisions"}],"predecessor-version":[{"id":114,"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/posts\/75\/revisions\/114"}],"wp:attachment":[{"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/media?parent=75"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/categories?post=75"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.kth.se\/blogs\/emd\/wp-json\/wp\/v2\/tags?post=75"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}