Simple yet confusing question.... Motor rotation>Pump rotation

SinePari

SinePari

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Oct 24, 2013
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Trouble shooting a bit of an issue with my press... I've just applied power and am not getting any pressure. For fear of burning something up, I've only run it for a brief couple of seconds to distinguish that something isn't correct.


My theory is that the motor is set to run (CCW) Counter Clock Wise, and I wired it that way because I was under the impression that this is the way the keyed shaft rotates when looking towards the power transmission/face of the motor...

The pump is setup to run Clock Wise... which I also understand that this is based on the rotation of the keyed shaft....

So in order to run the two successfully;

Motor (CCW)>====/====<Pump (CW)


I'm wondering now if the motors wiring diagram represents not the motor itself, but the peripheral equipment it's intended to run???





I'm thinking now that the rotation wiring diagram on the motor
 
Disconnect the motor from the pump, turn it on and see which way it spins? I've never trusted diagrams much...
 
Rgr that, glad I'm not completely off my rocker questioning the diagram... when I was assembling the lovejoy coupling there was a rotational arrow imprinted on the motors face, right at the base of the keyed shaft, identifying a CCW rotational direction, I even marked it with a sharpy on the motors shell knowing it would be covered up.... but I had to physically rewire it to be CCW...

I'm definitely thinking that the motor's diagram is a lie. Lies, all LIES!!!!

hopefully it didn't damage the pump... err...
 
We have lift off!....

The Leeson motor wiring diagram "directional rotation" refers to that which is receiving the transmission of power, not the rotation of the keyed shaft...


So for the next guy that uses a 5HP Leeson 111275; wire the motor according to the pumps rotational specs... If the pump calls for CW, wire your motor CW...

Now I have to troubleshoot a hydraulic issue...lol
 
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The joy of motors! I have one where the wiring diagram says the CW / CCW orientation is when looking at the back of the motor, which makes it the opposite when looking at the 'front' with the keyed shaft. In other words,

SinePari said:
...motor wiring diagram "directional rotation" refers to that which is receiving the transmission of power, not the rotation of the keyed shaft...
Click to expand...

I don't know if that's standard or what.
 
Mecha said:
The joy of motors! I have one where the wiring diagram says the CW / CCW orientation is when looking at the back of the motor, which makes it the opposite when looking at the 'front' with the keyed shaft. In other words,

I don't know if that's standard or what.
Click to expand...

You'd think someone smart would come along and lay down the law defining the standard of "which end of the motor is used in determining rotation".

I didn't embark on today's progressive leaps and bounds just to sit here and dribble over something so simple, yet so nauseatingly rich in frustration!

I kept on having to reassure myself that if I ever needed to set off a claymore mine, I would never question "this side toward enemy"....
 
I almost purchased a German-made motor for my grinder, until I saw the wiring diagram. Just a bunch of triangles, circles and squares. Can't trust electricity as it is, no need to mystify it further.
 
SinePari said:
You'd think someone smart would come along and lay down the law defining the standard of "which end of the motor is used in determining rotation".

I didn't embark on today's progressive leaps and bounds just to sit here and dribble over something so simple, yet so nauseatingly rich in frustration!

I kept on having to reassure myself that if I ever needed to set off a claymore mine, I would never question "this side toward enemy"....
Click to expand...

The convention in industry is to check motor rotation when viewed from the Non-Drive End of the motor.

It makes sense doing it this way because in many cases there will be something (being driven) on the drive end that will prevent an observer seeing the direction of rotation.
 
All shafts that rotate are described when viewed from the shaft end. Imagine a big set of clock hands on the shaft and the motor or pump body being the clock dial.....you can easily decide CW or CCW. Thus a CW pump is connected to a CCW motor.

In most all mechanical situations the descriptive designation is "from the observers POV". When dealing with animate objects ( people and animals) the descriptive designation is from the observed objects POV.
 
???:confused:???

And the frustration continues...

Stacy, I rewired the motor to run CCW because the pump specified that it ran CW. I did this under the reasoning that the pump's rotational direction was exactly as you described... As per the wiring diagram on the motor I wired it "CCW" under the same understanding that looking at the shaft end, would rotate CCW... Needless to say the diagram depicted on the wire housing of the motor did not not translate accordingly...

I went by your logic, which I believe to be correct, but our logic is apparently not universal.

I hope that made sense...
 
I reread your OP. Have you made sure that the oil has flushed through the system and bled out any air? The pump won't pump anything until it has oil in it., then you have to push/bleed all the air out the cylinder and hoses. A few seconds run time won't do that. As always, photos help.
 
But what about motors with a drive shaft on each end? The two ends appear to be spinning in opposite directions from the observer's POV! :confused:
 
bladsmth said:
I reread your OP. Have you made sure that the oil has flushed through the system and bled out any air? The pump won't pump anything until it has oil in it., then you have to push/bleed all the air out the cylinder and hoses. A few seconds run time won't do that. As always, photos help.
Click to expand...

Stacy,

I've got it rotating in the correct direction and I'm getting pressure. I'm going to go ahead and continue the troubleshooting issue in my WIP thread so people encountering the same issues as I don't have to hunt through the pile.
 
You should slap up a pic of your hydraulic setup.
 
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on most pumps the pick up is bigger than the pressure out, so think about the gears turning inside the pump and which way they need to be turning to pull from the suction side to the pressure side...
 
Well hell, Sinepari I didn't realize you were the mad fabricator behind the forklift press.
 
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