Question

I am trying to use a starter for a 3hp motor on a 120 vac 15 amp circuit. It keeps tripping out. What is going on?

Answer

OK, 1 hp is equal to 746 watts. Given all of the other circumstances of heat loss, power factor inefficiency, it is safe to say that a 1 hp motor requires more like 1000 watts. A 120 vac 15 amp circuit can on give a max of 1800 watts. If we do the math, we can see that the power requirements out weigh the ability of the circuit to run anything over 1.5 hp.
My 3 hp saw works on the same circuit? It is not the conventional hp rating that is given to your saw. It is the near stall measurement, if you were to keep it in that condition that the manufacturer measured it at, the saw would melt.

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FAQ Subcategory: None

This item was last updated on 2001-08-23
Document ID: 837

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