Yeah, these kinds of motors have been around for ages: 8-pole with rotor resistors, and 4-pole with open slip rings.
Quote: only works when the rings are closed (8 poles), when opened" there is no rotor current, no rotor magnetic field and no torque
But the thing is, what if the rotor...
Hi, Boom2,
I'm surprised that after performing a new rotor winding, you are unable to describe its configuration.
Please draw a diagram illustrating how you performed the winding, because as you reported, the motor operates at one speed but not at the other.
By the way, the type YZRDW250M-8/4...
Hi, Bum,
I presume it's a crane motor.
Yes, it's a two-speed wound-rotor induction motor. Regarding the rotor winding design itself, we know several (at least 10) different versions so far, from very simple to very complex ones. Keep in mind that there are no standards for the construction of...
Recommendation:
When inquiring about a specific electric motor, always provide a photograph of the motor nameplate to ensure an accurate response.
The attached diagram is marked as a2 and drawn somewhat like a4.
In fact, the diagram is incorrect for both a2 and a4.
The first thing you need to...
The same thing always happens.
Whenever you ask anything about a specific electric motor, first show its nameplate with the data at least.
For example, from your question it's not clear whether the 415V, 5.5 kW three-phase motor is designed to operate in a Wye or Delta connection.
It would be good to know more information.
Is the question purely theoretical, or does it concern a specific motor?
How will you increase the motor's speed? By using a VFD or some motor efficiency improvement?
And most importantly, is it a constant torque, variable torque, or constant power...
If the markings on the wires coming out of the motor are standard, the only thing you need to do is swap the wires labeled Z1 and Z2.
Winding Design and Motor Repair
Read the product description before you buy that junk.
BTW, this kind of post doesn't belong on electrical engineering. It's more suited for a hobby forum.
A winding diagram for this particular PAM two-speed winding, and for any other PAM, PPM, or Dahlander two-speed winding, can be found at the link below.
Link
Hi, eeprom,
Please attach a photo of the motor nameplate.
Provide a bit more information about the maintenance history of these motors.
Do the problems occur from the very beginning or only after rewinding?
Very often, the only measure that a service center takes in the case of "inverter...
Sorry JMGotts, but your last post and the diagram look a bit confusing.
Besides, you didn't draw the thermal protection that exists in the motor (usually close to zero resistance).
My suggestion is to take the motor to a service center where they can properly test, label, and connect it to...
