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Asynchronous motorunusual behaviour

  1. Oct 28, 2012 #1
    Hello everybody

    This is not a very advanced topic but if someone could take a few minutes to enlighten me on a problem i have with an AC clothes dryer motor I would much appreciate it. Some years ago this 350mA 75W 2500 rpm 2uF moteur wouldn't start so I replaced the 2,5 uF condo and that cured it. This time it seems a bit more complicated.

    Using polyester 250V condos I can get it to start in its usual horizontal axe of rotation position but I have to over 5uF and sometimes well it won't start at all even with 10uF.

    I took it out and managed to open it (rare thing these days....) to inspect the axis and lightly oil, everthing looked tip-top. Now here's what's strange :

    1. In the vertical axe of rotation position it sometimes starts without a starting condo', that for me is blasphemy. Is this not unusual?

    2. Sometimes it stops in , or I can turn the rotor to, a position where nothing will make it restart. Probably the motor is just a bit old in the tooth but it does turn very freely, apart from the axis I can't quite see what can age in this sort of motor.

    If someone can comment on these two points, thanks

    I've ordered a few proper condo's, they cost next to nothing, but I can't see any reason why they should do any better than the polyesters.
  2. jcsd
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