motor problem

If the water is clean then just leave the motor for a few days to dry out...

Then do an insulation test to check its dry enough before turning it on - if its only been in clean water for an hour or so there shouldn't be any problem.

John.

how is it tested for insulation

Like John says and with maybe a drop of oil on the bearins or a squirt of WD40 after it's dried out.

Insulation test... got a 'megger' ?.... A bit like a multimeter but uses a higher voltage..the old fashioned one' had a crank handle on the side. Used to get apprentices to hold the probes in one hand and wind the handle with the other...Baaaad Kitty.

Spray alot of WD-40 into it then dry air and then you should be able to use a mega ohm meter on all of the windings to see if it is ground accrossed it self.

Clean versus dirty would make a titanic difference and the bearings should be replaced. Disassemble the whole unit and use compressed air to get water out of all cracks, windings, etc. If it was salt water, maybe a clean water rinse to remove salt from between windings and anywhere dissimilar metals join. Bake it in the sun/oven/hairdryer to remove ALL water. And follow above advice with the megaOhm meter. My crystal ball predicts intermittent problems in your future. Good Luck.

This friend knows!

This is generally not a job for a beginner, so as you appear to be a beginner (you did not even know what a Megger is !), before you kill yourself (or anyone else near you), be clever and get a professional in to do the job properly....

It may cost more financially, but the job would get done properly with far less risk.

By the way, if the motor was immersed in salt water and it was not cleaned properly in the first 24 hours, it is probably so damaged now as to be mostly useless anyway......

As Andy says - If you need to ask how to do an insulation test you will need a professional to advise on the motor's condition.

If you spoke to me personally as a professional with this question I would have to say NO scrap the motor and buy a new one and get it fitted by someone who knows what they are doing.

John.

Knowing more about the motor would help. We are all making a lot of assumptions!

I mean it could be a 12v DC 35watt job or an umpteen horsepower 240v thing...what are we dealing with?

What we are dealing with Del is a typical CR4 question with almost no relevant information.

We've done it before and we will probably do it again, umpteen times......!!

By the time the Guy knows what to do, the motor will be a nice red ball of rust!!!

Owww Del likes to play with red balls of rust don't you Del?

Or was it red balls of wool???

John

Heh heh heh!!!!!

So it is THE END: A few jokes and CR4 interviewer after reading answers for his question just gone.

I have a feeling that the original Poster is long gone with his little ball of wool (sorry Rust)......

Yeh it's annoying when posters never reply or acknowledge especially.

I'd rather be slagged off by a member at least they have the courtesy to be identified!

(That's not an invitation...the open season on cats closed last week!)

Re: "Yeh it's annoying when posters never reply or acknowledge especially."...

My 2 cents-worth:

Perhaps there was 1-too-many "traces of nut" for the poster to sift through...

All posts referring to the fact that not enough info was given are certainly correct. The CORRECT response would most certainly HINGE on a couple factors not divulged within the post, such as the type of motor ("C"-frame/skeletal , induction , brush-type, ball bearings or sleeve?, plastic slot insulation or nomex paper?...etc.).

WD-40 may be suitable for SOME general cleaning duties on some electric motors, but is NOT a universal cure-all. Best followed by a "Safety-Solv" rinse and an oven bake-out (as a professional EASA Electrical Apparatus Repair shop would do).

After proper water-displacement/cleaning is accomplished, and properly addressing the bearing issue, new "Y"s in the troubleshooting flow-chart are reached. A "growler" can be employed to check the windings (single or 3Ø) for shorts between windings. The post mentioning the 'megger' test for grounded windings is called-for at this point as well (500V test if 120V 1Ø operation).

Finally, a "voltage source" (quote from post) most certainly CAN, and typically IS used if all checks-out to this point. For typical 110-120V 1Ø (single-phase) motors, a series of 100 watt light bulbs (in parallel sockets, allowing a sufficient amount of power for testing, while limiting the "fry-factor" power!) is employed to get the unit started back up and run for awhile (under no-load conditions), thus checking the switch mechanism (if split-phase, for kicking-out the Start Winding), and verifying whether it is suitable for returning to service.

How many here have made a "Dyno-Brake" for electric motor testing, using a couple of 2x4's ...?

I have had six pumps that feed the whole plant for water suppy under water several times before. They where 40-Hp, 480- three phase. Let them dry out about two weeks. As for the bearings go they should be sealed if not find out from the manufacture what type of grease and how much to add. If there is a next time and if possible leave the motor running, when we would recieve lot of rain fall we made sure that all the pumps where running, These pumps would be total under water and running!

Interesting first-hand experience... I wonder what type (rating) of motor they are...?

Having worked at G.E.'s DCMG dep't (Erie, PA) winding coils for both Navy Sub's and walking drag-lines (mining-monsters), and attended their 5-Star Motor school (Ft. Wayne, Indiana), and subsequently re-wound motors and generators in an EASA repair shop ... I would be surprised if these motors to which you are referring aren't either submersible, exposion-proof, or hostile-environment motors to begin with.

Even the hostile environment motors are not *rated* for submersible duty, and, given a sufficient amount of water within the windings, an operator is just asking for trouble leaving a 480V 3Ø motor running whilest submerged! Sealed bearings are meant for keeping-out dirt, and keeping *IN* the "lifetime" grease. They can certainly keep water out to a certain extent, but water under any pressure (i.e., depth) will force its way in eventually, and once it fouls the grease, the bearings will suffer severely, and rapidly (water's a lousy lube under speed, heat and load!).

"Lucky once... count your blessings!" Next time, think in terms of "an ounce of prevention..." and you'll probably come out ahead.

More smoke = less insulation.

Here is a good resource I found after hurricane Katrina. You need to click to download their pdf file, but it is worth the wait.

http://njaes.rutgers.edu/pubs/publication.asp?pid=FS968

Other resources, less specific to motors:

http://www.disaster-resource.com/articles/what_now_smith.shtml

NEMA document on water damaged electrical equipment

Also if you are a member of IEEE, you can download ANSI/IEEE 43-2000, A2 and A3 from their website. Non-members don't have access so I didn't bother with a link.

There is product, dry lube, called LPS1. It is non-conductive and dissplaces water. I once saw a demo where they sprayed an electrical motor with this stuff, started it up and then stuck it in water and it keep running. In a couple of plants they have replaced WD40 with it as it is also non-flammable and a much better product.

WD-40 is probably 50 years old, so it may be time for something new!!

I certainly always have a can of WD-40 handy.....

Ad finished!!!

I checked out LPS1 on the web, its 4x the price of WD-40!!!!