# my motor ignorance



## Honestly (Feb 3, 2011)

I stick mainly with residential and light commercial, but I have a friend who has asked me to help him get a large kettle going at his small bottling plant. He has a 240 single phase service. The motor on the kettle is used and he was told it was 3 phase. I assume this is correct, since it has a 460/230v rating on the nameplate? I am trying to size a phase converter, but I need hp. The nameplate is worn out and though V, A, RPM, FREQ and SF are obvious, I can't figure out which number is HP. Also, there is no "3" on it that I see, but there is a "1" at the top. Wouldn't it indicate if it was 3ph? Anyway, there is a 1.50, a 2.00, and a 0.80 if the picture isn't readable. Any help is greatly appreciated.


----------



## miller_elex (Jan 25, 2008)

Rub some more dirt into it, then snap another picture.


----------



## Malaking_TT (Dec 17, 2010)

And turn the camera over too


----------



## JohnR (Apr 12, 2010)

just by taking the amps given you can find the HP by going to 430.250T and looking up the equivalent horsepower under the table. I see that it is somewhere between 2 and 3 HP. 1660RPM Service factor of 1.15


----------



## Jlarson (Jun 28, 2009)

I'm saying the same thing as JohnR, 2-3 HP. I'd figure it as 3HP for the converter sizing IMO.


----------



## HARRY304E (Sep 15, 2010)

Honestly said:


> I stick mainly with residential and light commercial, but I have a friend who has asked me to help him get a large kettle going at his small bottling plant. He has a 240 single phase service. The motor on the kettle is used and he was told it was 3 phase. I assume this is correct, since it has a 460/230v rating on the nameplate? I am trying to size a phase converter, but I need hp. The nameplate is worn out and though V, A, RPM, FREQ and SF are obvious, I can't figure out which number is HP. Also, there is no "3" on it that I see, but there is a "1" at the top. Wouldn't it indicate if it was 3ph? Anyway, there is a 1.50, a 2.00, and a 0.80 if the picture isn't readable. Any help is greatly appreciated.


Remember 1 horspower is 746 watts so if you can find the amperage you can do the calculations and find the horspower.


----------



## Honestly (Feb 3, 2011)

Great. The 430 tables crossed my mind earlier, but I wasn't sure. Do you think its definitely three phase because of the voltage rating? I couldn't find a 3 on the nameplate. Also, the wires were cut from the previous hookup. Looks like three colored wires (non white), and a green eq gnd. I assumed this showed it was three phase, but being unfamiliar with motors, I didn't know if there may be an instance with three ungrounded leads to a single phase motor. Thanks again.


----------



## BBQ (Nov 16, 2010)

HARRY304E said:


> Remember 1 horspower is 746 watts so if you can find the amperage you can do the calculations and find the horspower.


It is not that simple.


----------



## hardworkingstiff (Jan 22, 2007)

Honestly said:


> Also, the wires were cut from the previous hookup. Looks like three colored wires (non white), and a green eq gnd.


Where are these wires? Are they hanging out of the motor junction box or are they the wires inside the junction box?

Since it's a dual voltage motor, I'll assume the wires you are talking about are what's coming out of the motor jb and not the wires coming out of the motor itself (into the jb). If they are, then I'd say between that and the voltage you can be pretty sure it's a 3-phase motor.


----------



## Honestly (Feb 3, 2011)

hardworkingstiff said:


> Where are these wires? Are they hanging out of the motor junction box or are they the wires inside the junction box?
> 
> Since it's a dual voltage motor, I'll assume the wires you are talking about are what's coming out of the motor jb and not the wires coming out of the motor itself (into the jb). If they are, then I'd say between that and the voltage you can be pretty sure it's a 3-phase motor.


Yes, hanging out of the motor jb.


----------



## Dennis Alwon (May 9, 2009)

Try this-- Still looks like a 3 hp- 230v/460v. Assuming 3 phase use T430.250 and you have 9.6 amps/ 4.8 amps-- anything you do here is a guess.


----------



## lefleuron (May 22, 2010)

Dennis Alwon said:


> Try this-- Still looks like a 3 hp- 230v/460v. Assuming 3 phase use T430.250 and you have 9.6 amps/ 4.8 amps-- anything you do here is a guess.


 Wow, not a very good tag buddy.

What I think I get off this tag-

at 230- flc is 6.34 amps.
at 460 flc is 3.17 amps 


1.15 Service factor

I think installed 4/20/90

What I dont understand is the part under the dual voltage stamp.

1.50 1.660
2.00 .8

I dont know if this is for a company supplied heater chart or something. the 1.6 and .8, one is half the other but what they are meant to stand for I dont know.


----------



## micromind (Aug 11, 2007)

I'm going to guess this motor is 2HP. 3PH.

A lot of motors have the '3 phase' written on the tag, not stamped. 

You'll need to open the box on the motor to determine what voltage it's connected for. Most likely there'll be 9 leads. If two or 3 motor leads are connected to each incoming power wire, then it's connected for 230 volts. If only one motor lead is connected to each incoming power wire, then it's connected for 460 volts.

If it needs to be re-connected and there's no diagram, post back with the lead numbers (if there are any), and we'll help you get it right. You'll need an ohnmeter. 

Rob


----------



## JRaef (Mar 23, 2009)

lefleuron said:


> Wow, not a very good tag buddy.
> 
> What I think I get off this tag-
> 
> ...


Save the image, open it in a picture viewer, change it to Negative Image, increase the contrast, decrease the brightness, add sharpness.

1.50 kW
2.00 HP 
0.80 pf 
1660 RPM (no . in there, it's a spec of dirt)
1.15SF
TEFC


----------



## JRaef (Mar 23, 2009)

Buy a 2HP 230V VFD that accepts 1 phase input, connect the motor as 230V 3 phase. The VFD will convert the 1 phase source to 3 phase for the motor. Most 2HP 230V VFDs will run that motor without de-rating. Do NOT use a motor starter, the VFD will become the motor starter. Adapt your controls to control the VFD.


----------



## K2500 (Mar 21, 2009)

JRaef said:


> Save the image, open it in a picture viewer, change it to Negative Image, increase the contrast, decrease the brightness, add sharpness.
> 
> 1.50 kW
> 2.00 HP
> ...


Now that, my friends, is ingenuity at it's best.


----------



## sbrn33 (Mar 15, 2007)

It's only a 1.5 HP motor. Just go buy a single phase motor. Cheap and easy


----------



## JRaef (Mar 23, 2009)

K2500 said:


> Now that, my friends, is ingenuity at it's best.


For years I wondered what value there was in even having the Negative Image feature in Photo programs, then one day I had a similar problem with an old nameplate. I figured it out when I looked at the actual _film_ negatives; Remember those? But to accomplish it that time I had to scan the actual finished photo and then electronically convert it to a negative image. You'd be surprised how much "hidden" detail you can make out in a negative image. Lets you blow it up to a large size too, something that is getting increasingly more handy lately...


----------



## JRaef (Mar 23, 2009)

sbrn33 said:


> It's only a 1.5 HP motor. Just go buy a single phase motor. Cheap and easy


Nope, FLC is too high for 1.5HP, and then how do you explain the 2.00 figure?

2.00HP x .746 = 1.492kW, close enough

You might be right about just buying a 1 phase motor though, probably a toss up cost wise.


----------



## micromind (Aug 11, 2007)

The nameplate doesn't list a frame size (not that I can see anyway), so it might be difficult to replace it with a single phase one. 

If it's belt drive, and the base can be drilled to accomodate a standard frame, then replacing it would make sense.


----------



## Honestly (Feb 3, 2011)

Wow. You guys are my heros  thanks.


----------



## navyman (Jan 26, 2010)

Is there any connection diagram inside the connection cover?
Almost all 3 phase dual voltage motors have nine leads. This motor could have been rewound for single voltage.


----------



## don_resqcapt19 (Jul 18, 2010)

JRaef said:


> Buy a 2HP 230V VFD that accepts 1 phase input, connect the motor as 230V 3 phase. The VFD will convert the 1 phase source to 3 phase for the motor. Most 2HP 230V VFDs will run that motor without de-rating. Do NOT use a motor starter, the VFD will become the motor starter. Adapt your controls to control the VFD.


Won't he need a larger drive? I think in general when using a drive as a phase converter you have to use a drive with a horsepower rating twice that of the motor


----------



## JRaef (Mar 23, 2009)

don_resqcapt19 said:


> Won't he need a larger drive? I think in general when using a drive as a phase converter you have to use a drive with a horsepower rating twice that of the motor


That's true as a general rule, but at 230V 3HP and below, _MOST _of the VFDs are built to take single or 3 phase input without over sizing (recently there has been a trend starting away from that practice though so you have to check to be sure). They basically use the same power components for everything up to 5HP anyway, so at 3HP and down, it ends up already over sized enough to handle a 1 phase input.

Which of course begs the question; "If they all use the same components anyway, why do they charge more for a 3HP drive than a 1HP drive?"

Answer: because they can...


----------

