Motor question

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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...
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could mean some shorted turns or binding bearings, (but you should be able to feel that by turning the rotor by hand) or it could mean nothing..
leave it run for longer and see how hot it gets..
Does it have a starter relay or cap that is defective?
Mark
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Mark wrote:

It has a starter relay that disengages properly. The start cap is new.
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HeyBub wrote:

Hi, Are you reading peak current or average current draw? When motor starts there is a surge of current.
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Tony Hwang wrote:

Average draw after the motor reaches speed.
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That seems to be way high for a motor that is not under any load. Either a faulty meter or the motor is bad.
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HeyBub wrote:

Is it possible for you to check the current draw with another kind of meter, say a conventional clamp-on ammeter?
That 17 amps being drawn when unloaded sure doesn't sound correct to me.
Jeff
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Jeffry Wisnia
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Should proly be 3 amps unloaded. 1 1/8 hp rating is kinda odd, eh?
I just bought a killawatt. I'll fool around some in the next cupla days. I'm curious as to how it handles power factors. If it is just calc'ing amps x volts, it's not really reading true watts.
Someone here once posted on how Con Ed type watt-meters work, in some detail, most of which ran over my head, but I'd like to take another look at that post, if someone has it marked. It was complicated enough (using some kind of hysteresis saturation of metal or sumpn, ie, intrinsically mechanical) that I wonder how a solidstate device can duplicate this. I guess if it calc'd the voltage wave form and the current waveform sep'ly, like on an oscilloscope, and determined the phase angle, it could be done electronically, but I'll find out by comparing with a clamp-on meter.
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Existential Angst wrote:

Hi, That is easy if voltage leadning current vice versa, measuring phase angle. Cosine Phi is power factor, right? Cosine 0 degree is 1 where V and A is in phase which never happens in real world since most load is inductive.
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They do read true watts, and are fairly accurate. They also tell you what the power factor is. So, all in all, pretty neat little gizmo.
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Zardo Zapp wrote:

Yes, I've compared them to reading from my Fluke 87 and they agree nicely. The Kill-a-Watt is a very handy and economical gadget. They are particularly handy when used with a Honda EU2000i generator camping.
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Zardo Zapp wrote:

Hi, Then the motor is sick.
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Could well be.
But, also note that the Kill-a-watt can get a little squirly if you exceeed it's max rated current.
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wrote:

Not necessarily. Some type of motors still draw lot of current with little or no load. What changes is the power factor. They aren't using much power because the current isn't in phase with the voltage. In other words, they look like a big inductor rather than a resistor. The power company hates these types of loads because there are still losses (heat) in their lines due to the high current going through imperfect wires, but the customer isn't paying much due to their meter not showing much real power being used.
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jeff_wisnia wrote:

Good idea. I'll dig out my clamp-on. Thanks for reminding me.
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jeff_wisnia wrote:

I don't believe the 13 amps either with no load. That 13 amps is at it's rated horsepower load.
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*With one horsepower equaling 746 watts even the nameplate rating sounds a little high. If it is still high with your ammeter you could have a bad bearing, but you should be able to hear that.
Let us know what you find.
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John Grabowski wrote:

The faceplate reads a clear "13.5 Amps."
Both the Kill-A-Watt (reluctantly) and a clamp-on ammeter show about 18-18.6 amps being drawn.
Interestingly, the clamp-on shows 18.5 amps on one wire and 16 on the other. The difference must be in heat. Or condensation.
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HeyBub wrote:

How does your actual utility voltage compare to the motor's nameplate voltage?
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wrote:

Cannot be. What flows in the one wire MUST flow in the other unless you have a SERIOUS ground fault.
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