10ee MG RPM slows from 800 to 500 under load - Page 3
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    I matched the two pulleys which slowed the exciter speed. the voltage went down to a range where i could adjust the resistor so i am now reading 118v between f1 and f2 when the spindle is off. Top spindle speed is around 2300 give or take. on a heavy cut spindle rpm may drop 50 rpm. voltage between f1 and f2 remains constant under load.
    Its all working well.

    I think the gen pulley was the oddball. it was almost 4". I just happened to have a 3.25" pulley with a 1" shaft sitting on my bench. I put that on and the change in exciter speed
    lowered the voltage by about 40 volts.
    then I adjusted the rest of the way down with the resistor



    Quote Originally Posted by Cal Haines View Post
    Please make sure that you change the file extension on you photos to ".JPG"; ".JPEG" files don't post full size.

    The exciter pulley definitely isn't original; it looks shop made. One of the photos in my archive show both pulleys on an MG set are "AK32" pulleys, which is an industry standard, 3.25" pulley. McMaster-Carr has pulleys that size for about $20 each: link

    The field voltage at the peckerhead is going to change when the motor is operating in field weakening mode, depending on how the speed control pots are set. What does the E1-E2 voltage (which is the output of the exciter) do when the spindle is stopped, running without load and under load?

    You definitely want to get the exciter voltage closer to 115 VDC. If the exciter is running over nominal it's also pushing up the output of the generator. The designers of the MG knew what they were doing when they selected that voltage.

    Cal

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    F1-F2 is not the right place to be checking when you're adjusting the exciter's output. There's rheostat in series with the exciter and unless you in the bottom half of the speed range, where the field rheostat has zero resistance, your readings will be low. Check it between E1 and E2 at either the terminals on the bottom of the DC control panel or at the MG terminal panel.

    Cal

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    I thought if the spindle is off, the voltage on F1 and F2 is the supposed to be 115v if I'm at around 700rpm on the rheostat.
    I'll check e1 and e2 at the terminal box tomorrow. thanks





    Quote Originally Posted by Cal Haines View Post
    F1-F2 is not the right place to be checking when you're adjusting the exciter's output. There's rheostat in series with the exciter and unless you in the bottom half of the speed range, where the field rheostat has zero resistance, your readings will be low. Check it between E1 and E2 at either the terminals on the bottom of the DC control panel or at the MG terminal panel.

    Cal

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    Quote Originally Posted by lectrician1 View Post
    I thought if the spindle is off, the voltage on F1 and F2 is the supposed to be 115v if I'm at around 700rpm on the rheostat. ...
    For square-dial DC panels, that's correct. When neither the forward (F) or reverse (R) contactor/relay is closed, contacts on F and R, wired in series, short across the motor field rheostat. On round-dial panels, the rheostat is in series with the field except for the brief periods of time when the field acceleration (FA) or dynamic braking (DB) relays are operating. The series contacts on the square-dial panel take the place of the DB relay for purposes of dynamic braking. So it sounds like you have a square-dial panel. Still, I'm interested in knowing what's going on with the output of the exciter itself when the spindle is stopped, unloaded and loaded.

    Cal

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    Quote Originally Posted by lectrician1 View Post
    ...Top spindle speed is around 2300 give or take. on a heavy cut spindle rpm may drop 50 rpm. voltage between f1 and f2 remains constant under load.
    That's just a skosh over 2% drop under (moderate, actually? [1]) load, and is rather GOOD as well as a major improvement - one tenth the 500-odd RPM drop with the "fixed" DC field supply before restoring to OEM inherent load-regulation?

    I'm not comfortable with the accuracy of your tacho readings, however.

    The MG's AC motor should No Fine Way be running at only the 3,000 RPM previously reported.

    If your tachometer is reading under, your 2300 RPM top would be in error as well. Unloaded, with OEM Voltages and optimal brush timing, FWD RPM should be a skosh ABOVE 2400 at the motor - 2500+ at the spindle.


    [1] A truly "heavy" cut for a 10EE is best tested with the compound removed and a monobloc 4-way directly mounted to the topslide of the cross. It isn't what they were INTENDED for, but what they CAN do is ... shall we say "impressive?")
    Last edited by thermite; 07-06-2021 at 07:35 PM.

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    at what rpm should the ac motor be running?

    what would you call a substantial cut, in thousandths with feed and rpm?








    Quote Originally Posted by thermite View Post
    That's just a skosh over 2% drop under (moderate, actually? [1]) load, and is rather GOOD as well as a major improvement - one tenth the 500-odd RPM drop with the "fixed" DC field supply before restoring to OEM inherent load-regulation?

    I'm not comfortable with the accuracy of your tacho readings, however.

    The MG's AC motor should No Fine Way be running at only the 3,000 PM previously reported.

    If it is readng under, your 2300 RPM top could be in error as well. Unloaded, with OEM Voltages and optimal brush timing, FWD RPM should be a skosh ABOVE 2400 at the motor - 2500+ at the spindle.


    [1] A truly "heavy" cut for a 10EE is best tested with the compound removed and a monobloc 4-way directly mounted to the topslide of the cross. It isn't what they were INTENDED for, but what they CAN do is ... shall we say "impressive?")

  8. #47
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    Quote Originally Posted by lectrician1 View Post
    at what rpm should the ac motor be running?
    AC motors have a synchronous RPM, based on line CPS and pole count. They then have "families" of slip curves from minimal RPM drop down to can-be-stalled for (a period of time) ELSE (indefinitely) for "torque motor" winding AKA electrical infinite springs.

    Elevator door closers have been a traditional torque motor application. I used them for TTY/Data punched paper-tape movement and for office automation continuous paper forms movement- both applications needing critical tensioning, and it had to be adjustable.

    The 10EE MG's synchronous RPM would be 3600. Synchronous motors HOLD their RPM so very well a primary historical use has been to serve as CLOCKS.

    A commmon slip-curve for a 2-pole motor is 3450 RPM.

    The "families" of slip curves otherwise have to do with whether a(ny) given motor has to exhibit high starting torque, high running torque, neither, or both. Motor-maker's publish this stuff as aids to the design Engineers who must make the choices for a(ny) given application. See NEMA Designs A, B,C, D, for stock families - all makers.

    If driven off a 50 Hz supply - or any OTHER - the RPM numbers obey the math.

    The ONLY way I can see your 10EE's AC prime-mover shaft clocking at 3,000 RPM is if it is being powered from a VFD set to 50 Hz, not 60 Hz, as Lost Wages Never-da is in a 60 Hz service area as far as utility mains. An RPC would not change that at all.


    what would you call a substantial cut, in thousandths with feed and rpm?
    On what size of machine tool?



    Absent a dynomometer, measured by inference. "In general".. any combination that holds power load to the nominal rated sustainable max HP, right off the final-drive motor's dataplate.

    For a round-dial 10EE, "Large-frame" Reliance?

    - Field @ 115 VDC, zero resistance inserted.

    - Armature @ 230 VDC & 12 Amps draw, motor RPM on spec.

    The RPM, DOC, & rate of feed to generate such a "full-rated load" otherwise depends on the nature, size & shape of the alloy being turned - and with what shape and type of tooling.

    For the same "shape" of cut and approach?

    "Generally.."

    - neg-rake Carbides have very high loads
    - sharp pos-rake Carbides much, much less,
    - razor (literally..) sharp pos-rake HSS/Cobalt for lower-yet.
    - very sharp pos-rake Tatung-G has even lower loading than HSS (it's a lower-coefficient of friction metal.)

    What folk actually USE is more dependent on the Alloy, shape being generated, tool LIFE with acceptable finish and size-holding, hence overall cost per part produced and to spec, not as a reject.

    TIME @ sustained acceptable cost and quality heads the list.
    Energy consumption is usually well down the list. It is one of the cheapest inputs.
    Last edited by thermite; 07-06-2021 at 08:11 PM.

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  10. #48
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    Default I wish you could just answer the question

    using another tachometer the gen is spinning near 3600 and the exciter is the same

    Thermite, when you give answers like this, it is a nuisance to even read through them.

    question: "At what rpm should the generator be running?"

    answer : 3600rpm
    I dont need the history of motors in the answer

    another question "what would you consider a substantial cut?

    Now you are a reasonable person
    We are on the monarch 10ee forum
    we are talking about a 10ee
    A reasonable person would assume I am using a BXA or AXA tool post with 1/2 carbide cutters or something similar

    So using the known parameters and the assumed parameters, you could just give an answer like this:
    "well going roughly 600rpm on mild steel the 10ee could easily take .250" at such and such feed rate with 1/2" carbide indexable cutters"

    Instead its sentence after sentence of nonsense
    With no answer at all

    I few posts back you said I was making a piddly cut @ .175 off an 8" diameter
    That comment prompted me to ask you what a substantial cut would be
    Why cant you just answer the question?

    Droning on and on does not make you appear like you know what you are talking about.
    Brevity is the soul of wit.shakespear


    Quote Originally Posted by thermite View Post
    AC motors have a synchronous RPM, based on line CPS and pole count. They then have "families" of slip curves from minimal RPM drop down to can-be-stalled for (a period of time) ELSE (indefinitely) for "torque motor" winding AKA electrical infinite springs.

    Elevator door closers have been a traditional torque motor application. I used them for TTY/Data punched paper-tape movement and for office automation continuous paper forms movement- both applications needing critical tensioning, and it had to be adjustable.

    The 10EE MG's synchronous RPM would be 3600. Synchronous motors HOLD their RPM so very well a primary historical use has been to serve as CLOCKS.

    A commmon slip-curve for a 2-pole motor is 3450 RPM.

    The "families" of slip curves otherwise have to do with whether a(ny) given motor has to exhibit high starting torque, high running torque, neither, or both. Motor-maker's publish this stuff as aids to the design Engineers who must make the choices for a(ny) given application.

    If driven off a 50 Hz supply - or any OTHER - the RPM numbers obey the math.

    The ONLY way I can see your 10EE's AC prime-mover shaft clocking at 3,000 RPM is if it is being powered from a VFD set to 50 Hz, not 60 Hz, as Lost Wages Never-da is in a 60 Hz service area as far as utility mains. An RPC would not change that at all.



    On what size of machine tool?



    Absent a dynomometer, measured by inference. "In general".. any combination that holds power load to the nominal rated sustainable max HP, right off the final-drive motor's dataplate.

    For a round-dial 10EE, "Large-frame" Reliance?

    - Field @ 115 VDC, zero resistance inserted.

    - Armature @ 230 VDC & 12 Amps draw, motor RPM on spec.

    The RPM, DOC, & rate of feed to generate such a "full-rated load" otherwise depends on the nature, size & shape of the alloy being turned - and with what shape and type of tooling.

    For the same "shape" of cut and approach?

    "Generally.."

    - neg-rake Carbides have very high loads
    - sharp pos-rake Carbides much, much less,
    - razor (literally..) sharp pos-rake HSS/Cobalt for lower-yet.
    - very sharp pos-rake Tatung-G has even lower loading than HSS (it's a lower-coefficient of friction metal.)

    What folk actually USE is more dependent on the Alloy, shape being generated, tool LIFE with acceptable finish and size-holding, hence overall cost per part produced and to spec, not as a reject.

    TIME @ sustained acceptable cost and quality heads the list.
    Energy consumption is usually well down the list. It is one of the cheapest inputs.

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  12. #49
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    Quote Originally Posted by lectrician1 View Post
    using another tachometer the gen is spinning near 3600 and the exciter is the same

    Thermite, when you give answers like this, it is a nuisance to even read through them.

    question: "At what rpm should the generator be running?"

    answer : 3600rpm
    I dont need the history of motors in the answer
    Wrong. You clearly DID need it.

    Anybody who paid attention in grade school science would have KNOWN the basics for AC motors @ 60 CPS to the second, 3600 to the minute, (1800, 1200, 900...less "slip"...) and spotted the tachometer error right away. Same error as was ALSO giving you WRONG spindle RPM figures.

    another question "what would you consider a substantial cut?

    Now you are a reasonable person
    We are on the monarch 10ee forum
    we are talking about a 10ee
    A reasonable person would assume I am using a BXA or AXA tool post with 1/2 carbide cutters or something similar
    Wrong again. QCTP are aids to rapid production wherein multiple tool CHANGES are required. AND NOT to high precision, specifically.

    A 'reasonable person" might not want anything to do with the excessive overhang of an Aloris-style QCTP on a super-precision lathe.

    Multifix, Tripan, or 4-Way, rather.


    So using the known parameters and the assumed parameters, you could just give an answer like this:
    "well going roughly 600rpm on mild steel the 10ee could easily take .250" at such and such feed rate with 1/2" carbide indexable cutters"

    Instead its sentence after sentence of nonsense
    With no answer at all
    Sorry if it is THAT far above your energy level.

    - D'you have even the LEAST idea how many THOUSANDS of types of indexable Carbides, shapes, and coatings or NOT coated, are "out there" and how VERY differently they can perform?

    Which have I over-estimated?

    Native intelligence? Perhaps overly-hopeful, but I don't THINK so.

    Simple sloth, rather than intellectual energy? A lack of willingness to learn what you had not already known is far the more likely.

    I few posts back you said I was making a piddly cut @ .175 off an 8" diameter
    That comment prompted me to ask you what a substantial cut would be
    Why cant you just answer the question?
    I did answer it.

    Why can't you understand that it is relative to a HOST of variables... same machine, same available power budget, different alloys, workholding, tooling, toolholding, and type of cut?

    Ultimately it IS about power "budget" to make the chips. The LATHE's ken ends there. It delivers to design goal. Or it does not.

    Your one WAS not. It is NOW.

    Application, tooling, and technique toward the product is not the 10EE's job.
    It is not some other PM member's job to tell you what to make nor how nor how hard to push the limits.

    It is YOUR job.

    Droning on and on does not make you appear like you know what you are talking about.
    Brevity is the soul of wit.shakespear
    "Brevity" indeed. Fast and furious earned me enough by age 49 to retire and have the luxury of taking more TIME to try to help the newer arrivals .. the slower learners.

    Or even the simply lazy ones.

    You came into the room doing stuff on assumptions - in a "highly sub optimal manner" with:

    - Presuming that DC bench supply would be an improvement rather than a detriment.

    - Missed that all the in-forum info shows matching MG & exciter pulleys.

    - Did not even have tacho readings that were "possible" for the MG's AC motor..

    - ignored about HALF of what Cal Haines was trying to convey to you..even as to WHERE one should measure Field Voltages.

    Annnd .. FINALLY get yerself steered to a better outcome.

    To wit? Restored to OEM.. which is about as "sustainable" as can be.. because all others can follow the same documents too - and repeat the known-good results.

    And now you want to blame the messengers for patiently dragging your reluctant ass off "knows what he knows" about 'modern' DC bench supplies vs "obsolete" Monarch / Reliance / Ward-Leonard bedrock expertise, one hundred and thirty MIKE FOXTROT YEARS already PROVEN?

    You SHOULD be glad you got to good results. Proud, even.

    "Vicious?" "Whining?"

    Meahh... not as if volunteers have to CARE ... nor have our "paychecks docked", is it?

    OTHERS can learn to trust the OEM engineering and JF restore it ....from what you went through.

    Because it JF WORKS. And that ... another useful EXAMPLE ... is what makes it all worthwhile to some among us. "Personalities" be damned.

    It is, after all.... "only the internet".

    QED.

    You wasted quite a lot of TIME fighting the OEM design. Perhaps more, yet refusing to read?

    BFD. "Late" still beats "never".

    One more wastebasket-fire put out. You are up and running now.
    Should be all you need.

    Go, now, and "run what you (finally) got!"

    Other stuff to do, here..
    Last edited by thermite; 07-06-2021 at 04:29 PM.

  13. #50
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    more nonsense
    you know all your posts are blocked on my PM page
    I have blocked your posts for close to two years. Just because I grew tired of having to read paragraph after paragraph of nothing.
    More times that I can count, I read your posts, sentence after sentence, after I'm done, I asked myself,"what is he even saying"
    It just got to be frustrating.
    I am not alone either.
    Dont get me wrong, I appreciate your input. But please, just the facts.



    Quote Originally Posted by thermite View Post
    Wrong. You clearly DID need it.

    Anybody who paid attention in grade school science would have KNOWN the basics for AC motors @ 60 CPS to the second, 3600 to the minute, (1800, 1200, 900...less "slip"...) and spotted the tachometer error right away. Same error as was ALSO giving you WRONG spindle RPM figures.

    Wrong again. QCTP are aids to rapid production wherein multiple tool CHANGES are required. AND NOT to high precision, specifically.

    A 'reasonable person" might not want anything to do with the excessive overhang of an Aloris-style QCTP on a super-precision lathe.

    Multifix, Tripan, or 4-Way, rather.

    Sorry if it is THAT far above your energy level.

    - D'you have even the LEAST idea how many THOUSANDS of types of indexable Carbides, shapes, and coatings or NOT coated, are "out there" and how VERY differently they can perform?

    Which have I over-estimated?

    Native intelligence? Perhaps overly-hopeful, but I don't THINK so.

    Simple sloth, rather than intellectual energy? A lack of willingness to learn what you had not already known is far the more likely.

    I did answer it.

    Why can't you understand that it is relative to a HOST of variables... same machine, same available power budget, different alloys, workholding, tooling, toolholding, and type of cut?

    Ultimately it IS about power "budget" to make the chips. The LATHE's ken ends there. It delivers to design goal. Or it does not.

    Your one WAS not. It is NOW.

    Application, tooling, and technique toward the product is not the 10EE's job.
    It is not some other PM member's job to tell you what to make nor how nor how hard to push the limits.

    It is YOUR job.


    "Brevity" indeed. Fast and furious earned me enough by age 49 to retire and have the luxury of taking more TIME to try to help the newer arrivals .. the slower learners.

    Or even the simply lazy ones.

    You came into the room doing stuff on assumptions - in a "highly sub optimal manner" with:

    - Presuming that DC bench supply would be an improvement rather than a detriment.

    - Missed that all the in-forum info shows matching MG & exciter pulleys.

    - Did not even have tacho readings that were "possible" for the MG's AC motor..

    - ignored about HALF of what Cal Haines was trying to convey to you..even as to WHERE one should measure Field Voltages.

    Annnd .. FINALLY get yerself steered to a better outcome.

    To wit? Restored to OEM.. which is about as "sustainable" as can be.. because all others can follow the same documents too - and repeat the known-good results.

    And now you want to blame the messengers for patiently dragging your reluctant ass off "knows what he knows" about 'modern' DC bench supplies vs "obsolete" Monarch / Reliance / Ward-Leonard bedrock expertise, one hundred and thirty MIKE FOXTROT YEARS already PROVEN?

    You SHOULD be glad you got to good results. Proud, even.

    "Vicious?" "Whining?"

    Meahh... not as if we have to CARE ...

    OTHERS can learn to trust the OEM engineering and JF restore it ....from what you went through. Because it JF WORKS.

    And that ... another useful EXAMPLE ... is what makes it all worthwhile to some among us.

    "Personalities" be damned.

    It is, after all.... "only the internet".

    QED.


  14. #51
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    Quote Originally Posted by thermite View Post
    Anybody who paid attention in grade school science would have KNOWN the basics for AC motors @ 60 CPS to the second, 3600 to the minute, (1800, 1200, 900...less "slip"...) and spotted the tachometer error right away.
    Unfortunately they dont teach that anymore, I don’t even think in high school. Now a days they seem to teach to the test.

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    voltage across e1 and e2- 116v with the spindle off
    spindle on: voltage raises slightly to around 118 and stays there loaded or unloaded.





    Quote Originally Posted by Cal Haines View Post
    Still, I'm interested in knowing what's going on with the output of the exciter itself when the spindle is stopped, unloaded and loaded.

    Cal

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    Quote Originally Posted by TBJK View Post
    Unfortunately they dont teach that anymore, I don’t even think in high school. Now a days they seem to teach to the test.
    No fear. Yew Ass of Eh? seems to have offshored brains and initiative - mayhap traded for "instant gratification" trappings, such as ear-buds, movie-theatre-cabin tall-trucks, and "recreational drugs", easily as fast as they sent sweaty boots and capable hands off to under-employment.

    But ever valiant Kenya has our back!

    https://eie.uonbi.ac.ke/sites/defaul...L%20SYSTEM.pdf

    You thought US Big Corp were hiring from Africa, India, Middle-East, and Asia for cheap labour?

    Not so.

    They hire folk who actually know their s**t, "give a damn".. can and WILL "read AND write.." and are willing to WORK to succeed ... is wot they are doing.

    Lo, these many years. Already.

    "America" isn't just a "place".

    It's a state of MIND!

    Thank God in her infinite mercy...

    Oh.. not that we've quite "died" yet, either:

    Creaky-old Ward-Leonard for EV applications, anyone?

    (PDF) An Investigation of the Ward Leonard System for Use in a Hybrid or Electric Passenger Vehicle


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    Quote Originally Posted by lectrician1 View Post
    at what rpm should the ac motor be running? ...
    Per the notes on the square-dial wiring diagram, drawing EE-3216, the AC motor, DC generator and the belt-drive exciter all run at 3450 RPM. I assume that would be at full load. The MG's AC motor is not a synchronous motor, it's an induction motor. All induction motors have a degree of slip and run below the synchronous speed, the greater the load, the greater the degree of slip. 4% slip at rated HP is about right for AC induction motors of this size. Speeds will be closer to 3600 RPM with the spindle off.

    If I had remembered that the note also specified the generator and exciter speeds, it would have answered the earlier question about the pulleys being the same size.

    Cal

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    Quote Originally Posted by thermite View Post

    Anybody who paid attention in grade school science would have KNOWN the basics for AC motors @ 60 CPS to the second, 3600 to the minute, (1800, 1200, 900...less "slip"...) and spotted the tachometer error right away. Same error as was ALSO giving you WRONG spindle RPM figures.
    Another way I think of it, is if you're living in the USA, our electricity is run at 60hz or 60 cycles. That's both for home single phase, and industrial 3 phase regardless voltage. Well at least for low voltage at 600v or below, not sure about true high voltage stuff. Some other countries use 50hz.

    But its a simple math that must add up correctly. Yes I have seen 900 rpm motors and gens, but the 3 most common motor speeds are 1200, 1800, and 3600. This is no accident, its part of the math. Notice 60 (ie 60hz) can be divided by those motor speeds evenly. 1200 divided 60 = 20. 20 rpms per cycle/hz.

    60 goes into 1800 30 times. 30 rpm per hz.

    60hz x 60rpm per hz = 3600rpm motor.

    So long as your electricity is 60hz there's no escaping the math. The number of poles in a motor are part of the math as well. The only way to change that math of a rated motor speed is to reduce or increase the 60hz. If you reduced hz to 59, then 59 x 60 would equal 3540 rpm on a 3600 rpm rated motor.

    And by contrast you could increase the cycles such as 61hz. 61 x 60 would equal 3660rpm on that 3600 rated motor.

    This is how vfd's work, by manipulating utility electric service hz or cycles. Turning them up or down from the 60hz.

    If you have a diesel or gas powered generator, the math is the same, but sort of working from the opposite side. Engine runs at 1800rpm, gen makes 60hz. Bump engine speed to 1830rpm and now you have 61hz on gen end. Lower engine speed to 1770rpm and gen end has 59hz.

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    You're talking about synchronous AC motors. There are very few synchronous AC motors used in machine tools. (For one thing, they require separate field excitation.) Look at the name plate of any AC motor in your shop and you won't find an RPM rating that's a nice multiple of 60. They will be 4 to 5% below the synchronous speed. And again, that's the rated speed at full load. At no load, they'll be close to synchronous, but it you had an accurate enough tachometer, you would still find them slightly below synchronous.

    See this link: Induction motor - Wikipedia

    Cal

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    Well I'm about to button things up. Lathe is running great. I will run it for a couple weeks to make sure everything stays status quo. Thanks everyone for all the help.

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    Quote Originally Posted by Cal Haines View Post
    You're talking about synchronous AC motors. There are very few synchronous AC motors used in machine tools.
    True enough as far as it goes, but "oddly" one of the places they CAN be found, historically, is in uber stable AKA high-precision..... ta da... Ward-Leonard drives!

    Not that a 10EE needs that.. Not in that part of the system. As far as we know.

    That said, the "overkill" required so they do not fall on their nose under duress would make for less-efficient spend and poor use of tight space.

    Does that mean it wasn't EVER done?

    Well.. constant surface speed.. early Atom bomb parts? Remote manipulation of the lathes whilt thye were housed inside a containment area? "Outboard" mounting of the MG rigs already a known variation?

    Might not be public information, even yet-today, either way?

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    Quote Originally Posted by thermite View Post
    Quote Originally Posted by Cal Haines View Post
    You're talking about synchronous AC motors. There are very few synchronous AC motors used in machine tools.
    True enough as far as it goes, but "oddly" one of the places they CAN be found, historically, is in uber stable AKA high-precision..... ta da... Ward-Leonard drives!
    ...
    Just to clarify, you are NOT suggesting that 10EE's have synchronous AC motors. Correct?

    Cal

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    Quote Originally Posted by Cal Haines View Post
    Just to clarify, you are NOT suggesting that 10EE's have synchronous AC motors. Correct?

    Cal
    Why on Earth would it matter what *I* think might have existed, Manhattan Engineer District's resource set?

    You didn't even believe the independence of that DC "bench" supply was a detriment or that the Exciter, Generator, and load-motor of a proper Ward-Leonard system are all teamed in an inherent feedback loop set..... with seriously complex maths..

    read 'em if you can:

    Ward Leonard control - Wikipedia

    ....the physics of which have not changed from Harry Ward-Leonard's time. MIT and subsequent .... to modern-day Nairobi, Kenya.. or Utah looking at EV possibilities for the future.

    Intil "our man in Las Vegas".. was convinced... to put the f**ker back INTO service OF his truant 10EE ..

    ...try it.

    ...and PROVE it so!

    "QED"

    Took a few years?

    BFD. Who even keeps score?



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