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Electric Motors/Motor rotation


I have pretty decent experience with electric motors, having swapped them out on numerous lapidary (rock cutting and the like) machines, for both 115 and 230V. I have run across one that I don't recognize, and unfortunately the cover plate is missing. It's stamped GE 5KH45HD(or O?)178X. It's an older model, 1/3HP 115VAC 1725RPM Two codes I don't recognize are NPRZ and Code P. It's CCW viewed from the motor end and I need CW rotation. The thing I don't get is there are 5 terminals, numbered 1, 2, 3, 4, and 6. I can send a drawing if you like. Anyway terminals 1 and 2 are hardwired to two cut off leads, but the motor came to me with 4 and 5 connected to the line in (working fine, just the wrong rotation for me). The tab on 6 is broken off. I suspect that changing 5 for 6 (which involves soldering the lead) will change the rotation. In other words, the former owner broke the lead off of 6 and put it on 5, I guess he didn't care which way it rotated. So the big question is, if I do that, can I fry the motor switching it on for a second to check the rotation, and do you think it's likely that is the case?

Tim  are you saying it came to you with 4 on a line, and 5 on a line  or  4 and 5 on one line and the other line on say 1?

Typical dual voltage   1234 are runs,   series 23 and line to 1 and 4 for high voltage, 13 to line and 24 to line for low,   for with    5 and 8 as starts connected one to each line,  reverse rotation    swap 5 and 8      Code P is no concern,  NPRZ not sure of,   GE has more types and models than Carters has pills,       

Line to 4 and line to 5 seems very wrong,    but it could work,  many misconnected motors will fire up,  if the load is way below rating, the misconnected poles push through what little load there might be,    because is runs NEVER MEANS it is connected correctly,  only when the applied voltage and a dyno are used can you look at the amps and heat, and tell,

And motor leads 1 and 2 are hanging in the breeze,    1 and 2 should be one half of the run winding,      3 to 4 the other half,     in order to have dual voltage, you need a series connection for high and a parallel connection for low,         then a start winding tied in parallel across the runs which is switched out by the stationary switch.

I could guess all day,  finding anything by model for GE is just an adventure in frustration.

Sounds like the motor is running off half the run,  which is possible lightly loaded,   as long as the start is out of phase with the run,  that creates rotation by induction into the shorted rotor,          

It really appears to me  that if it looks like   1234 and 6 are the accessible leads,     1 to line   4 to line high  pick a side for 6 for rotation,        13 to line   24 to line for low voltage pick a side for 6 for rotation,     anything on there stating cw  or ccw     not uncommon for a dual voltage motor to have a fixed rotation,       

The big question,  if you bump for rotation will you fry the motor,   very unlikely,   most can be abused way more than a bump for rotation,   but I think you need to get the entire winding one line, and from what you have explained that is not the case,   MEAR Services Inc    816-650-4030 phone number,     let me know what happens when you swap them,   do you know the running current compared to nameplate tolerances?

That needs to be clamped so you know what amount of current you are using,  

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Three phase/ AC DC single phase motors, controls, any problems or failures, motor installation, performance issues, connections. All other electric motors/gearboxes/apparatus. Specialty repair concerns, obsolete motors and solutions. Other mechanical or specialty equipment. See my profile under Home/electrical at this site


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