On Sun, 1 Nov 2009 06:48:24 -0600, "HeyBub"
wrote:

Ashton Crusher wrote:
On Fri, 30 Oct 2009 09:53:32 -0500, "HeyBub"
wrote:

bud-- wrote:
HeyBub wrote:
I have a 115v, 1 1/8 HP motor with a faceplate rating of 13 Amps.
It actually draws 17 Amps (according to the Kill-A-Watt) with no
load.

Does the difference mean anything important?

Thanks in advance for any advice.

P.S.
I haven't run the motor for more than a couple of minutes...


Are you misreading 18 as 13?

The table in the NEC gives 16 amps for an "average" 1 HP 120V motor.
That, along with the nameplate value of 13A is for a fully loaded
motor. Are you operating with a mechanical load?

Watts might also be of interest. A 1 1/8 HP mechanical load is 840
watts. Then there are losses that add. I never looked at the watts
of an unloaded motor. Should be far less - most of the current is
reactive.

You may be on to something - that, coupled with the limitation of the
Kill-A-Watt to 15 amps, leads me to go ahead and perform the "Smoke
Test."


I didn't see the 15A limit on my Kilowatt. I put it on my compressor
motor and it started at about 16 amps when I turned it on, and went up
to 19 amps just before shutting off when it reached full pressure,
about 120psi. The Kilowatt seems ok for having been overloaded.

Limits:
Max voltage 125VAC
Max amps 15 A
Max power 1875 VA
http://www.p3international.com/produ.../P4400-CE.html



Most likely that's the rating for continuous duty. Mine was only on
for maybe 3 or 4 minutes.