3 phase motor question
3 phase motor question
(OP)
I recently purchased a new motor for a fluid pump application to replace a 6 year old motor. All of my motors here are 3 phase and all simply have 3 leads coming from the motor. This new motor has 6 leads T1,T2,T3,T4,T5,T6. When I asked my supplier how it should be wired, he told me to wire T4, T5, & T6 together & T1, T2, T3 to the power leads. Did this, tested, checked rotation and all was fine. Put to load & 1/2 hour later, motor overheated & shut down. After cooling, would not restart & repeatedly tripped power supply breaker. The motor in question is a hyundai, 30 HP, 575 volt, 1770 rpm, 29 amp rating. S.F. 1.15. Tested voltage at feed and each leg reads 230 volts. Can anyone tell me what might have happened? Faulty motor, or incorrect wiring? thanks in advance





RE: 3 phase motor question
RE: 3 phase motor question
Am I missing something? If this is the situation, I can see why it failed. The motor voltage must match (or at least be close) the supply voltage. If the supply voltage is too low, it will draw too much current and overheat.
Perhaps your motor is rated for multiple supply voltages (many are). If one of the rated voltages matches your supply, you need to connect the terminals in the configuration shown on the nameplate for the supply voltage.
Do you have overload protection for the motor? If so, it apparently didn't work.
RE: 3 phase motor question
RE: 3 phase motor question
If you are referring to your phase to phase voltagfe being 220V, then you have 220V 3 phase. You do not add them together to get 660V!
And if you are not in Canada, the chances of you having a 600V service are practically nil.
"Venditori de oleum-vipera non vigere excordis populi"
RE: 3 phase motor question
RE: 3 phase motor question
What went wrong with the 6 yr old motor? You may have a pump problem or some how the load has increased. Has the pressure or flow changed recently?
Your phase to phase voltage needs to be balanced also or it will cause overheating. When you put another motor in check the amp draw on each phase.
Barry1961
RE: 3 phase motor question
RE: 3 phase motor question
RE: 3 phase motor question
RE: 3 phase motor question
575V motors are single voltage Delta wound, and are to be connected as follows:
L1 to 1 & 6
L2 to 2 & 4
L3 to 3 & 5
That is right out of the book.
The other connection would have given you a wye connection, which would only produce 1/3 torque.
"Venditori de oleum-vipera non vigere excordis populi"