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Electric Motors/1950's Leland repulsion induction motor

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QUESTION: Looking to help out a handicapped friend that purchased a house with an elevator that needs the motor replaced. Any info would be greatly appreciated. Its a Leland repulsion induction motor, Type RD, 1/2 hp,FR. 4c66z, 230 v., Duty 1/2hr, 8.8 amp,1725 rpm, PH 1, CY 60,Ref.14052 PU 4777
We are at our wits end. I priced conversions to the system but it was totally out of his price range. Thanks for any help you can give and God Bless.

ANSWER: You did not get my first reply?   Let me know,  I want to make sure you got it,

---------- FOLLOW-UP ----------

QUESTION: I did not receive any replies. Please send again, thank you.

Answer
Wonder what happened to that    that was long  real long,   

Ok anytime you talk about moving human beings  $$$$$  liability in everything,   so in order to make this thing work,  you gotta fly under the radar,   

I need to know this   

That is an expensive motor  even a new one can be had,   but cost is way up there    for just general purpose,  add on moving a human    elevator duty,  lift duty    five time the price and it is the same damn thing

Who says it needs to be replaced?   Why  what is wrong?

The techs who know jack about repulsion induction are few and far in between,     

Do we have service report saying the brush mechanism is worn out, the fields are shorted the rotating armature/rotor is shorted    what is the problem?

YOU least expensive way out of this is to fix what you have  which is a low end RPM high torque but able to accelerate to a running speed,   coast and brake.

We need to start with either removing this motor from the picture or simply fixing it and done,

I don't know who said what is right or wrong,   but not many elevator guys are motor guys they are elevator guys      ever seen an elevator penthouse?    They understand THEIR MOTORS,  but not the internals and how to fix them   they can identify what is wrong maintanance that kind of thing,   but   I see this all the time     all the time for 4 decades  

Something with a motor doesn't do whatever  gotta be the motor,   hell it aint even half the time it is really the motor      

I would say the motor might not be performing  but did anyone check the contacts and check for voltage drop to the motor at the motor?

Find that out,   if we got nameplate voltage at the motor,  then a repulsion induction motor fails in these modes,   brushes get short   loose spring tension,  arc,  arc burns more brush shunts, spring, brush surfaces      it stops working,   

I need to know what is wrong with the motor      not it needs replaced,  and that is what you are going to get from most places because it is old technology but damn good technology and with a bit of maintenance and keeping the contactor in good shape the brushes at a reasonable length   they can go for a 100 years easy,    

They are great devices for the purpose they were designed and are hard to find,   

So lets start there,    

Next an interface is not a huge deal,   you can put a half horse induction motor in place,  install a VFD Variable Frequency Drive,   interface it to the up and down controls  and done  

Stair lifts dont have complex priorities on calls  who has been waiting to go up in elevator one versus elevator eight   so no need for a PLC<      the VFD,     it depends on brand and so on but at 230 volt and most are able to convert 110 to 220 right in the VFD and no transformer is needed,    most have around 40 to fifty user defined paramenters  not a huge thing,   

The main parameters are ramp up speed,  so you don't jerk the chair on accel   down or up,  coast,  overload inside,  a setup of parameters,  so that it starts up at 20 hertz accels to 60 in x seconds,  can be set for a predetermined amount of length   revolutions,  whatever,  it then decels  and coasts into the limit top or bottom  brake is set,   reverses  is ready to go the other direction,     

But then you got a cheap CHINA Made 1/2 HP tin can motor,  that will do the trick   I would find a used surplus cast iron frame old one   yours is a 66 frame  really a 66Z FRAME WHICH MEANS THE OUTPUT SHAFT IS NOT STANDARD TO WHAT STANDARDS THEY DID HAVE BACK THEN,  IT PROBABLY MEANS IT HAS SOME KIND OF EITHER STEPPED SHAFT OR GEARED SHAFT CUT RIGHT INTO THE MAIN ROTOR SHAFT WHICH SLIPS INTO A GEAR CASE,      z MEANS NOT STANDARD SHAFT,   DONT SAY WHAT JUST IT IS NOT STANDARD 66 FRAME DIMENSIONS,       

Now there are way to get around that  use the old motor shaft as the drive pinion  machine a shoulder for a pulley and go it that way,    push a new shaft into the new motor matching existing,         

Drive around $300 or so but remember it has a NEMA ONE Enclosure, overload protection reversing,  40 more parameters you dont have now,    so it is workable,    and you buy it like you are driving a pump or something    there should be other centrifugal or friction safeties on the lift on top of the motor brake,          

But I say lets find out what is really wrong,   if we can fix the existing motor and clean up any burnt contactors on your reversing mechanism,  that is you most cost effective fix hands down, but until I know for sure what is wrong,   we can only guess the worst    everything is burnt up,        now we go and find a used surplus with the same dimensions if not modify,  install and done,     

If YOU WANTED TO UPGRADE to fancy VFD   the ride is better I understand more detailed ramping and decel  so smoother     plus speed control    which there are limits provided by your local KING     we got a lot of them now days   so gotta do what the king wants,  so stay under the radar    it is just as safe  efficient, as the existing,         

HOw is the rest of the lift, brake, rails, seat, controls,  so on?

NEw lifts are built with VFDS from the get go,    and I have seen some amazing prices for a standard weight one floor lift     INSTALLED IN A DAY     which I could see that happening  

But you want low low cost    then fix the motor,  if not reasonable   we look for a surplus motor that is in running shape hopefully has the same worm shaft, step shaft, double shaft, whatever    if not modify it,       plus it in and go,  

Next put your old mechanical parts driven with a VFD,     and a new modern frame motor,      

There are going to be codes, and not many can be danced    but if you stay on the straight and narrow   no extra bells and whistles   if it load tests it usually passes in most places around the country   

There is a fix to this,  I cannot guarantee it is going to be dirt cheap  I can guarantee we will look from the least expensive option and go up as needed          

Get me a motor evaul report on that motor,      once we get any info,  great if not we ask for some,    

Let me know

Will

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Will

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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

Experience

30 plus years in the electrical motor and apparatus repair industry. VP level management of repair facilities, current owner of my own specialty repair and consulting firm.

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EASA, IBEW [retired], other specialty organizations, Lubrication, Vibration EDI, Tribo-electric Councils

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Currently fielding concerns at this site under "Home Electrical"

Education/Credentials
4 year technical, College level specific courses, EASA repair courses, vibration analysis electronic and electrical trade school.

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