Is there a difference between induction motors

Discussion in 'General Electronics Chat' started by Camoz, Jul 4, 2012.

  1. Camoz

    Thread Starter New Member

    Jul 4, 2012
    Hi all,

    I am new to this forum, but I have spent a few hours trying to find the answer to my question without success (so I apologise if this question has already been answered, and if so could someone please provide a link).

    My question may require more information, but I will give you what I know at this stage, please let me know what other information might be required.

    I have a woodworking table saw which was running with a 2hp single phase 50hz 2850rpm class "a" (not sure what class a means, but thought it might be important) 60 degrees C. The motor has packed it in (and the place I took it to, suggested it was not repairable).

    I have a friend who is willing to sell me a dust extractor for a great price, my idea is to take the motor from the dust extractor to use on the table saw (obviously I would need to either have the same shaft size or change the pulley, but that is not an issue). The plate seems to share the same details as above (except the table saw motor says 9amps and the dust extractor motor says 12 amps, also the dust extractor motor is a newer motor).

    My question is are these motors basically the same, will the dust extractor motor work Ok, if I use it with the table saw, or is there something I am not aware of (e.g. the table saw motor is designed to handle a heavier load for longer etc.)?

    If the answer is that it can be used, then are there any circumstances to look out for, if I want to do something similar again in the future (I have a few 3 phase machines which I have considered converting to single phase, and dust extractors seem to be the cheapest way to buy a single phase motor, especially when I start to get up to 3hp). Does the motor class have anything to do with it?


  2. cork_ie

    Active Member

    Oct 8, 2011
    The simple answer to your question is yes, you should have no problem.
    Generally, the most important characteristics for any induction motor are :

    Frequency, (50HZ or 60HZ) ,HP rating , (whether continuous or intermittent) Start Torque, motor speed,(which can be overcome by varying pulley sizes) and start current draw.
    Three phase motors have better start torque and lower start current draw and are always a better option above 1.5HP in most applications.
    For a quick tutorial on induction motor classes see here:
    As there are so many questions like this, on AAC, on a regular basis perhaps a page could be added to the E-book on "Motor Classes"