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Electric Motors/wiring 2 start and one run cap. to a single phase 230V motor


I have a motor out of a  steam cleaner with three black wires coming out of it where  the capacitors go.  one wire is tagged [O], another is tagged [E] and the 3rd wire is unmarked. Any loose wires that were with it are lost. The capacitors were two 704 MFD and one  37 MFD with a resister soldered across its contacts. The brand name has worn off of the plate. what is stamped is still readable;FIRST LINE 366636x28861. Second Line: 184T    F1297. Third Line: 6      DP. Fourth Line: 208-230. Fifth Line: 28-26. Sixth Line: 1725.  Seventh Line: 60    1    H. Eighth line: 1.00   L    G . Ninth Line: 53   90. Tenth Line: 40C  AMB-CONT. Last Line: 5-1040. Could you please school me on the proper wiring of the capacitors?  I'm a machinist but I do have a little bit of electrical background. I would really appreciate any help on this one. thank you


I can only assume but it appears you have  permanent split capacitor motor,    [PSC]

Like most furnace blowers,  and because this is probably running some sort of reverse blower   to make is draw in versus blow out,    it makes even more sense,    

But then you have two caps,  which now makes me think you have a cap start/cap run motor, because the huge difference in microfarad ratings,   

The resistor is common on many caps,  it's function is to squash the back emf    coming from the motor fields when power is removed  and the back voltage is sent to the cap, as the fields collapse,     very common,        it is probably a metal can cap, the larger value cap is probably some sort of round cap,  plastic case,       and YOU have a 184T frame  pretty big for a  PSC motor,    

The O and E    mean nothing to me or anyone else but the person who put them on,     arbitrary markings,    184T is  NEMA frame size first line    OEM markings,   Second   frame size  NEMA,   

third line   DP is    Drip Proof enclosure,  which means it is an open frame motor    fifth line  maybe a model or something,    sixth   RPM   1725  normal speed for a four pole motor,   seventh line     60 cycles or hertz     also common frequency of US AC power, also line 7 = 1 as in one phase, or single phase, eighth line  1.00  service factor,   meaning it runs constant at rated voltage and rated load,   [a service factor of 1.15 would mean you had 1.15 more or less voltage, load,  etc  and still get constant or continuous running without damage,   ninth line some sort of OEM identifier,   tenth line  40C  is the temperature rating,  very common,  meaning the rise of the winding temp will operate at a max of 40 degrees centigrade,   so if the ambient is overly hot, the rise of the overall temp is OK at 40 C degrees above ambient,   last line    5-1040  again some sort of OEM marking,     so pretty much a basic nameplate,       the problem is you have loose caps and only three wires?

Most likely the two run caps   the plastic high value caps where in parallel,   the other the metal can at 37 is the start cap,  but with just three internal leads, out,   hard to say how the OEM wired it, there is for sure wires missing, some probably are jumpers that run into and out the jbox,      but to tell you how with nothing more than someones own markings  impossible,     

We could try and ohm it out with an ohm meter but that is one long process,       and it involves manually closing and opening the start switch,   and a lot of trial and error, as each OEM wires their motors as they feel,     maybe the two run caps were in series,   I doubt it,  but could not rule it out    
Best thing to do now, is send me some photos,  hopefully I can identify something,  and give you some guesses where to start,  this is very common,   and normally when all the wires are off the caps,     it means the previous owner was trying to troubleshoot a problem with it,  and gave up   abandoned the wires at the cap opening,    and got rid of it,       

my personal email  is below  I think        I cannot see it from this screen, but it is,      snap me some photos    if there is a cover plate at the main connection box or plate,    and look on the back side, sometimes there is a very complete diagram hidden there,   if not  we try to guess after I see it,    or photos, anyway,     if nothing makes sense,   best bet is to take it to a local motor shop and have them  wire it,  test the insulation value,  make sure there was not a problem that someone was trying to fix,      

It should take about an hour to wire it up,      at whatever the shop charges,  I would guess  $75.00 an hour   somewhere in there,     sorry I have no standard three black wires to 6 cap terminals connections  but I think you can see why,        so lets start with photos and make a decision from there,   I think the O could just as well be a  or Q  not likely the motor OEM Markings more likely the previous owner,  

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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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