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Discussion Starter #1
Motor Peckerhead Issues! Please Help!

Hello all!

Having an issue here and would like some feedback from the community!

I work at a sand and gravel operation and we just installed a new shaker deck on site. The motors are mounted on top of the shaker deck and not on a pedestals beside it. With this configuration the motors are experiencing the full vibration of the deck. The deck has been in service for less than two weeks and we have had two issues with the wiring inside the pecker head. The actual connections are standing up to the vibration but the conductors and their insulation are rubbing through causing shorts and/or opens in the circuit. We ended up rubber taping the length of the conductor to give it a better chance against the vibration but I feel that this will just prolong the inevitable. Apparently the manufacturer of the deck sent some sort of padding to go into the pecker head but we didn't see it. I have tried to find solutions for this online but I am striking out. One suggestion that I read was to pack the pecker head full with duct seal. I feel this would work but it could cause quite a mess especially if the motor heats up.

Does anyone else have an solutions to suggest.

Thanks!
 

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Discussion Starter #2
Hello all!

Having an issue here and would like some feedback from the community!

I work at a sand and gravel operation and we just installed a new shaker deck on site. The motors are mounted on top of the shaker deck and not on a pedestals beside it. With this configuration the motors are experiencing the full vibration of the deck. The deck has been in service for less than two weeks and we have had two issues with the wiring inside the pecker head. The actual connections are standing up to the vibration but the conductors and their insulation are rubbing through causing shorts and/or opens in the circuit. We ended up rubber taping the length of the conductor to give it a better chance against the vibration but I feel that this will just prolong the inevitable. Apparently the manufacturer of the deck sent some sort of padding to go into the pecker head but we didn't see it. I have tried to find solutions for this online but I am striking out. One suggestion that I read was to pack the pecker head full with duct seal. I feel this would work but it could cause quite a mess especially if the motor heats up.

Does anyone else have an solutions to suggest.

Thanks!
 

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Ready Mix concrete plant electrician
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So you have a 2 bearing vibratory screen with the motor mounted to the screen itself? What brand screen is it? This sounds like some kind of imported dumpster fire to me. Packing the JB to stop wire wear sounds like a ghetto repair for a poor design.
The 2 bearing screens that Iv'e seen mount the motor to the main frame and use more than the typical amount of usually B belts to compensate for the loose belt slippage from the motor mounting.
I would for sure contact the manufacturer and make them give you exact directions on a new install.

BTW, welcome to the forum and thanks for taking the time to fill out your profile.
 

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Retired IBEW inside wireman
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That just sounds like a bad design from the get go. Is fed by flex or cord? Not helping you much here -but a lot of sharp minds around will help out.
 

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Bilge Rat
motors and controls.........
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I've never seen a motor mounted on the vibrating part of a screen before but I have seen them mounted on the vibrating part of a crusher feeder.

When I make these up, I'll get some scrap belt and cut it in pieces to separate the conductors. I also keep the motor leads and incoming wire fairly short and I never use flex or sealtite, only flexible cord usually type SO or even better, G-GC.

It helps to get a single-voltage motor because there are only 3 or 6 leads compared to 9 or 12. Fewer splices this way.
 

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I agree, the bearings will go on this unit soon.

I had a lot of vibration tanks in the forge, never would we directly connect something like that.

Cheers
John
 

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Also, are there shipping bolts at the motor- mounts that needed to be 'backed off' at installation to de-compress a heavy spring or rubber pad? Nice to see a picture.
 

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Switch to a tool wire s/o type cord in a lazy loop then add a spring to the loop so the cable flex's rather then than bending in the same spot. (also avoids the weight of the cable handing on the mjb connector)
The padding is normally a piece of rubber belt cut so it covers the inside of the box ( T shape). I don't see a problem with duct seal as packing.

Hopefully the motor is designed for shaker duty. We use to PM our screen motors and replace the flex cable once a year as the copper stands tend to break in the insulation.
 

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I've never seen a motor mounted on the vibrating part of a screen before but I have seen them mounted on the vibrating part of a crusher feeder.

When I make these up, I'll get some scrap belt and cut it in pieces to separate the conductors. I also keep the motor leads and incoming wire fairly short and I never use flex or sealtite, only flexible cord usually type SO or even better, G-GC.

It helps to get a single-voltage motor because there are only 3 or 6 leads compared to 9 or 12. Fewer splices this way.
If you’re talking about the offset weighted double ended motors, I’ve been around several but wire abrasions are never really a factor.
Usually the guy dropping the coffee table size slab of material over the side and ripping the cable right out is the problem.
Back to the OP problem, the design is the real issue, any “fix” is a crutch. Maybe dip the wires in some Yellow 77 and shoot some Great Stuff foam in and let er rip.
The vibration is going to murder the motor bearings and the base bolts will be constantly loose. A Grip/Power Band style belt will be a must to keep belts from picking.
 

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Bilge Rat
motors and controls.........
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I was actually thinking of belt-drive but I've seen those vibrator motors too. I greatly prefer the air ones but they take a pretty fair-size compressor........

The soap is a good idea, I've never used it.....yet.......

cahulls, what kind of a motor is it?
 

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Sleeved the conductors on a vibrating parts cleaner, it lasted over a month. (The length of the job, I could pull it apart tomorrow and see how they held up.)
 

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I was actually thinking of belt-drive but I've seen those vibrator motors too. I greatly prefer the air ones but they take a pretty fair-size compressor........

The soap is a good idea, I've never used it.....yet.......

cahulls, what kind of a motor is it?
I'm not familiar with belt driven vibrators, do you have a picture by chance?
The air vibrators we use in R-mix are air hogs for sure and you would need a big screw compressor to feed it. The oily discharge from the vibrators would look like the Exxon Valdes spill in a few months.
 

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Wrap everything in friction tape. Multiple layers. It should be a normal part of a motor termination anyway. For this I guess you'd need to wrap the conductors as well. In your case though even that might not be enough. Even if you pot the the damn peckerhead I suspect the conductor in the flex is going to rub through eventually. Its a crazy idea to shake a motor that much.

My potting remark gave me an idea though. Itd make replacement a pita but you could gel or silicone the whole thing, feeder flex included. Raychem might make something suitable.

I agree with this wholeheartedly:

Back to the OP problem, the design is the real issue, any “fix” is a crutch.
 

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I pretwist and then use wire nuts. Solder pots rule.
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You didn't say how. IG the motors are.
If your feeding them and making splices with to much wire in the head, that could be part the problem.
You shouldn't have to cram 5' of wire into a 3" box.
 

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Bilge Rat
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I'm not familiar with belt driven vibrators, do you have a picture by chance?
The air vibrators we use in R-mix are air hogs for sure and you would need a big screw compressor to feed it. The oily discharge from the vibrators would look like the Exxon Valdes spill in a few months.
The belt drive type are like most normal screens where the motor is mounted to the frame and the belt drives a shaft with an imbalanced weight.

In this case, I thought maybe the motor is mounted to the screen and not the frame. Could easily be wrong though.
 

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Mounting motors in bad places, OEM style is not all that uncommon. I have seen motors mounted on The ram of punch presses and have seen many vibrators. The latter must be on the vibrating table or trough to work. Mounting motors on rams not so much. Whats a few more feet of hydraulic hose.

OP why not put the packing material you missed into the connection box? After all its what they gave you to prevent this.
The guys above have some ideas you should look at. Padding the conductors seems the way to go.
 

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The belt drive type are like most normal screens where the motor is mounted to the frame and the belt drives a shaft with an imbalanced weight.

In this case, I thought maybe the motor is mounted to the screen and not the frame. Could easily be wrong though.
I understand what you’re saying now about the feeder drives. I think the OP is saying the motor is actually mounted to the vibrating screen.
Deister, Pioneer, and Robins all mount their motors on the frame and not being shaken like a Bond martini.
 

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Discussion Starter #19
Thanks for all your replies.

Sorry if I didn't describe the set up well. In the manual the drive system is described as a double-shaft overhead drive system with direct mounted motors. The motors are set up with V-Belts. I am trying to attach some pictures but not sure how to. Let me know.
 

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Thanks for all your replies.

Sorry if I didn't describe the set up well. In the manual the drive system is described as a double-shaft overhead drive system with direct mounted motors. The motors are set up with V-Belts. I am trying to attach some pictures but not sure how to. Let me know.
You need 20 posts to upload pictures. It goes fast. Trust me.
I removed your duplicate post that was above.
 
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