×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

1hp irigation pump hooked up wrong

1hp irigation pump hooked up wrong

1hp irigation pump hooked up wrong

(OP)
I accidently hooked up a new motor to 110v supply and the motor was set to 220v.
I ran the motor for about 30 min or so then gave up. The next time I tried the motor cycled in and out a little. I then discovered my mistake and switched the motor to 110. Now it just makes an awful humming sound and smoke starts coming from it. I am wondering if there might be a way to save the motor????

Thanks for any help

Brian

RE: 1hp irigation pump hooked up wrong

If it is smoking when it is getting the proper voltage, you probably have developed turn to turn shorts. Too late, it's probably cooked.
Unless this is a very special and very expensive motor it will be cheaper to replace it than to rewind it.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: 1hp irigation pump hooked up wrong

I would say if there's smoke coming from it, it doesn't sound good. Smoke will usually be the varnish on the windings having overheated somewhat.
I'm surprised your upstream protection ( fuse or breaker) didn't provide any trip to the circuit.

RE: 1hp irigation pump hooked up wrong

Probably lost that motor: 200.00 dollars. 400.00 in labor and time already. Maybe 800.00 or more if you keep fighting the motor to try to save the 200.00

RE: 1hp irigation pump hooked up wrong

It could still operate for years after letting 'some' smoke out. My buddy's 5HP single phase compressor has let a little out over the years whenever it was started incorrectly (with head pressure) before a proper head-unloader was installed.

A much bigger problem is why it's not turning at all on proper voltage and then smoking. I believe your load is just too much for that motor. It actually ran on 240V but can not (ever) run on 120V (perhaps).

There are TWO possibilities.
1) The Start or Run or both capacitors (if it has them) where damaged by the 240V.

2) The motor does not have enough torque to get past the centrifugal switch and hence leaves the start winding engaged which will always start smoking in about 3 seconds and fry totally in about 10. Hence, your motor is undersized for the application.

Keith Cress
kcress - http://www.flaminsystems.com

RE: 1hp irigation pump hooked up wrong

Does the motor have a nameplate? Post a picture of the nameplate, and one of the motor itself. It would reduce the guesswork if we have some idea what type of motor this is. smile

RE: 1hp irigation pump hooked up wrong

(OP)
thanks for all the help already guys!!
I will try to get a picture. It is a 1hp a.o. Smith motor on a sta-right irrigation pump. It will work on either 220 or 110, comes from factory set to 220.... I hooked up to 110 supply and ran it for 30 min. it ran but I did not get any water up. Motor smelled a little hot but I blew it off to a new paint burning smell. Then next time I ran the pump trying to get the water up.. the motor ran but was cycling on and off a little like when a pressure switch is used. then it just started to hum and smoke.
I think I will try to put on a new capacitor and see if that works. If not then I'll replace the motor.

again

thanks for the help
Brian

RE: 1hp irigation pump hooked up wrong

Sounds like the motor was running at very high slip due to the voltage being low. Speed probably dropped below the kick-out for the starting winding which would explain the smoke. Sorry to say that I don't have a lot of hope for this one. neutral

RE: 1hp irigation pump hooked up wrong

The best hope is that in the race to failure between the capacitor and the winding insulation, the capacitor won, because that's easier to replace...

"Will work for (the memory of) salami"

RE: 1hp irigation pump hooked up wrong

It is my understanding that rewound motors are better than when they were new. In your case this motor can not be anything greater than 2 hp so buy another one because I suspect that the rewinding job will be costlier. Do a simple resistance test of the winding to find out if you have a shortcicuit.

RE: 1hp irigation pump hooked up wrong

(OP)
Turned out to be an expensive lesson for me. I replaced the motor. Cost me $180.00. The upside was that I was able to get water back on to my customer. The grass can keep growing and I keep getting paid! Hopefully I can use the parts from blown motor to rebuild a pool motor that needs bearings. (Same motor)

Thanks with all the help

Brian

RE: 1hp irigation pump hooked up wrong

(OP)
No Keith, I am in St. Pete, Fl. You go about 25 feet and hit water!

thanks again

c'ya next time I screw something

Hopefully a long long time. Lol

RE: 1hp irigation pump hooked up wrong

St Pete? Heck, you can go either sideways or down 25 feet and hit water.

Go 25 feet up and the water will come down and hit you most summer afternoons.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources