Re: Mysterious shift in saw alignment
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I don't know that?Chinese made motors are necessarily?poor or overrated, you just get what you pay for (sometimes less!).? Remember it's the American parent company that specified the motor on the Grizzly and?HF .? They chose to advertise its horsepower?as power output, as Grizzly used to (not sure now), or maximum motor-current?x voltage converted to horsepower, so is power input as HF do (and thus is overrated by 100-200%). Chinese?made stuff can be very well made or very poorly made, depending on how much the customer is willing to pay.? Looking back to when I was a child in the 1950's; 'Made in Japan' was a by-word for 'crappy' but not now.? I think the Chinese made stuff is better than the Japanese stuff was, or Taiwanese or Korean stuff for that?matter, at an equivalent stage of that country's industrial development. The running temperature?of a motor, as Jim indicated, is highly variable.? It is specified according to the temperature rating of the insulation around the wire in the motor winding, called 'winding insulation class' or just 'class' on the motor plate.? The following classes are recognised.
Where the motor is rated to run continuously, it can operate indefinitely below its max operating temperature given by its class.. My 1987 saw had a?Class?A motor which burned out and was replaced with a?TEFC class F,?the other two (yr2000 and 2020) are Open class E motors. Old Class A motors had relatively poor insulation on the wire, that broke down above 105C?(220F), so they necessarily had thicker wire (i.e. more copper) to keep the temperature?down and so weighed much more than higher classes of motor. but you can still burn yourself on a Class A motor operating within its normal parameters.? Modern TEFC (totally enclosed fan cooled) motors are generally class F or H and you'll burn yourself very quickly on these, even operating at relatively low power outputs, and they can run all day at over 300F!? Mnfr's are always trying to get more out of less, and one of the more recent innovations?is copper coated aluminium wire for the windings.? Not sure how this will pan out in the long run. but aluminium has almost as high heat and electrical conductivity as copper at 1/3 the weight and inertia, so it will find a place. American made, or Chinese made, they run at the temperature dictated by the actual load, run time and their winding insulation class - jv On Thu, Mar 24, 2022 at 1:12 PM Bill Armstrong <bill_1955@...> wrote: Chinese made motors, are highly overrated. That's why I replaced it with |
John Vreede