300 HP Motor Housing Terminations

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joebell

joebell

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New Hampshire
I went on a service call yesterday for a 300 HP motor that had a malfunction. It seems that one of the terminations (split bolt connectors and rubber tape) had worn itself out against the cover and grounded out. I noticed all three split bolts were loose when I opened the tape. I should explain that this motor runs a peice of equipment at a recycling center and vibrates quite a bit.

I'm wondering if the split bolt connections are the proper termination or is there something else out there that I could use in its place, or were the split bolts not tightened correctly to begin with? Any and all sugestions are welcome.

Thanks
 
Insulated lugs are the Caddilac....I call them "Monkey Knuckels" :smile: However if you want to re-use the split bolts try this...Tighten it down, then take a hammer or your Kleins in one hand and the split bolt in the other. Wrap firmly on the back of the split bolt a few times. This settles the copper alignment and works out the slack in the threads. Re-tighten and repeat again. This allows you to get them tight with out stressing the threads.

And always, apply a layer or two of "back tape" (sticky side up) then proceed with the normal tape layers, 130C or pads. The next guy will thank you as it can be removed very easy. One slice down the side, and across the back, and it practicaly falls off in your hand.....:D Well maybe not that easy...
 
I like the Burndy insulated taps too.

Another option that might work well for you is compression lugs. Make sure to get some rated for the fine stranded motor wire and bolt them together.
 
And still another option. use ball point type lugs with 2 set screws,the deep ones. bolt the flat sides of the lugs together using washers and lock washers. then use rubber mastic or splicing tape and a regular electrical tape over that. Benn using that combo for years with large motors with no failures. JoE the old,old motorman.
 
stew said:
And still another option. use ball point type lugs with 2 set screws,the deep ones. bolt the flat sides of the lugs together using washers and lock washers. then use rubber mastic or splicing tape and a regular electrical tape over that. Benn using that combo for years with large motors with no failures. JoE the old,old motorman.
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Ball point lugs? thats a new one on me...what is it?
 
And still another method that I have used for years. Use a double set screw ball point lug for each connection that doesnt have any lugs. (most if not all motor manufacturers supply thier motors with lugs that the electrician without the proper stuff cuts off,thus the split bolts) Lat the flats of the lugs back to back and bolt with hex bolts,washers and lockwashers.Tighten bloody tite. Tape with mastic or splicing tape 3 waraps minimum. Overtape with scotch 33 3 wraps min. and voila you have a connection that should withstand vibration and wear thru. The problem with single ball set connectors is that if you mess with or roll your connections they will loosen up. I have used this double ball connection sor years with no failures. OF course if you have acess to the proper crimp lug thats the best. I have used copper welding cable lugs and a hammer/anvil welder lug crimping tool and that also works great on fine strande motor lead wire but not on stranded copper xhhw. Joe the old, old motorman.
 
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