China Neodymium And Ferrite Magnets Manufacturer & Supplier 
Today, I am strolling a well-known domestic motor forum when I found such a topic related to magnets, an engineer asked the original rotor with 4 tile magnets replaced with 4-pole magnet ring does not turn what is the problem?
First of all, we need to confirm that the number of poles of the magnet is the same as the original, if the number of poles of the magnet is the same, turn is not a problem, the network is because of the replacement of the magnetic ring is 6-pole, rather than 4-pole lead to the detection of the number of poles of the magnet can be so that the magnetic pole test piece / observation piece.
The accompanying photo shows a ceramic ferrite segmented permanent magnet, taken from a Courage magnet manufacturer.
If the magnet pole number is correct but still can not turn what may be the reason?
If the number of poles is correct, the magnetic ring tends to arc coefficient is greater than that of the block, there are different grades lead to too large a counterpotential, counterpotential is higher than the drive voltage can not be turned, there is also too much torque toothed groove will lead to not turn.
The installation of the multi-pole ring on the rotor must also be precise, including accuracy of radial and axial position and consistency with the stator air gap. Improper mounting can result in uneven air gaps, eccentricity or tilting of the rings, all of which can affect the distribution of the magnetic lines of force, reduce motor efficiency, or even cause the rotor to fail to turn.
The above is about the rotor magnet replacement does not turn after the introduction of related issues for reference, there is a need for quotation proofing motor multi-pole magnet welcome to call contact Courage.
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