newbie Posted September 11, 2008 Report Share Posted September 11, 2008 Hi all, i'm dealing with lab experiment of squirrel cage induction motor for the purpose of educational training.im really not understand with this 2 types of machine as the spec below. MV1009-405 INDUCTION MOTOR SQUIRREL CAGE GENERAL DATA 50Hz 60Hz 4pole machine 1.1kw 1400 rpm 1.1kw 1700rpm star (Y) 380-415V, 3.0A 380-415V, 3.0A delta (D) 220-240V, 5.2A 220-240V, 5.2A moment inertia J= 0.0023kgm^2 MV1009-695 INDUCTION MOTOR SQUIRREL CAGE -same with MV1009-405 but for 380-415 3-phase delta.With this machine it is possible to do star/delta starts for 380-415 lab voltage my question is : wat is different between this 2 types? wat is different between the frequency for MV1009-405 machine? wat is different for star and delta for MV1009-405 machine? i really hope u can help me since i'm fresh graduate and dun have a lot of knowledge about electrical machine... thank you.. Link to comment Share on other sites More sharing options...
marke Posted September 14, 2008 Report Share Posted September 14, 2008 Hello newbie Welcome to the forum When you connect a motor in star, you have a lower voltage across each winding than when you connect it in delta. For example, if you are in Europe where the supply voltage is 400V three phase, then connecting a motor in delta will result in 400 V across a winding and when you connect it in star, you get 230 volt across each winding. Changing the voltage across a winding, alters the flux in the iron and thereby changes the torque that a motor can produce. There is a maximum flux density that the iron can operate at, so you must not connect a voltage higher than the design voltage across a winding, but reducing the voltage across a winding essentially reduces the ratings of that motor. i.e. connecting a delta designed motor in star, effectively reduces that motor to one third of the electrical rating. The maximum voltage that can be connected to a winding is limited by the maximum flux density in the iron and this is controlled by the number of turns on the winding. Best regards, Mark. Mark Empson | administratorSkype Contact = markempson | phone +64 274 363 067LMPForum | Power Factor | L M Photonics Ltd | Empson family | Advanced Motor Control Ltd | Pressure Transducers | Smart Relay | GSM Control | Mark Empson Website | AuCom | Soft Starters Link to comment Share on other sites More sharing options...
kada Posted November 7, 2008 Report Share Posted November 7, 2008 Hi! Two frequencies 50Hz and 60Hz correspond to two speeds 1400 rpm and 1700rpm. Nominal voltage should be stated for each nominal frequency (50 or 60) so you could set appropriate voltage to get nominal flux. E.g. if motor nameplate says there is nominal voltage 400V for nominal frequency 60Hz it means the motor will be saturated (flux higher than nominal) for the same voltage but 60Hz frequency. Link to comment Share on other sites More sharing options...
Mohanjith Posted October 19, 2009 Report Share Posted October 19, 2009 Always see the Name plate in the motor normally 220v for Delta Connection 380-400V for Star for Below 3Kw Motors(IEC) Link to comment Share on other sites More sharing options...
rachel12 Posted January 17, 2011 Report Share Posted January 17, 2011 Hi. I am also doing a project on same topic and i had the same question. I found here more help. Thanks guys for helping me also. Link to comment Share on other sites More sharing options...
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