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Re: How to find max-current?

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On 5/24/2017 3:47 PM, Dave, I can't do that wrote:
> ...
> I there some rule of thumb by which I can guesstimate the max current I can **safely** put into them to get 1/3-hp or 1/2-hp?
...

The current limit is determined by the heat it generates.  Motors fall 
into classes according to the heat rise that they can tolerate.  You 
might be able to guess the class of your motor, or you could assume some 
middle-of-the-ground. I used 100C for a motor that I tested.  I measured 
the temperature by measuring the resistance of the windings.  Or, to put 
it more accurately, I measured the change in temperature by measuring 
the change in resistance.  I did this while applying the max current 
that I had to the motor with the rotor locked.

Bob

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How to find max-current? "Dave, I can't do that" <davenpete@gmail.com> - 2017-05-24 12:47 -0700
  Re: How to find max-current? makolber@yahoo.com - 2017-05-24 13:42 -0700
    Re: How to find max-current? "Dave, I can't do that" <davenpete@gmail.com> - 2017-05-25 12:12 -0700
  Re: How to find max-current? bitrex <bitrex@de.lete.earthlink.net> - 2017-05-24 20:16 -0400
  Re: How to find max-current? Phil Allison <pallison49@gmail.com> - 2017-05-24 17:54 -0700
  Re: How to find max-current? Don Y <blockedofcourse@foo.invalid> - 2017-05-24 17:56 -0700
    Re: How to find max-current? "Dave, I can't do that" <davenpete@gmail.com> - 2017-05-25 12:10 -0700
      Re: How to find max-current? Don Y <blockedofcourse@foo.invalid> - 2017-05-25 13:18 -0700
  Re: How to find max-current? John S <Sophi.2@invalid.org> - 2017-05-24 22:54 -0500
  Re: How to find max-current? "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-05-25 08:45 -0500
    Re: How to find max-current? "Dave, I can't do that" <davenpete@gmail.com> - 2017-05-25 12:07 -0700
  Re: How to find max-current? Neon John <no@never.com> - 2017-05-27 15:38 -0400
    Re: How to find max-current? tabbypurr@gmail.com - 2017-05-27 13:49 -0700
      Re: How to find max-current? krw@notreal.com - 2017-05-27 20:04 -0400
        Re: How to find max-current? tabbypurr@gmail.com - 2017-05-27 17:34 -0700
          Re: How to find max-current? Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> - 2017-05-28 09:56 -0400
            Re: How to find max-current? Neon John <no@never.com> - 2017-05-28 18:55 -0400
              Re: How to find max-current? Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> - 2017-05-28 23:15 -0400
                Re: How to find max-current? Neon John <no@never.com> - 2017-05-29 12:05 -0400
        Re: How to find max-current? Neon John <no@never.com> - 2017-05-28 18:52 -0400
  Re: How to find max-current? Bob Engelhardt <BobEngelhardt@comcast.net> - 2017-05-29 23:30 -0400

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