Wiring up a Static Phase Converter
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    Default Wiring up a Static Phase Converter

    The accompanying document specifies 10 gauge wire for connecting to the main. So I diligently ordered some and a panel that can handle 10hp. Panel arrived so I started mounting it and placing the converter so it can be wired up. Surprise! When I opened the static phase converter everything is wired up with 14 gauge! Still shaking my head. Not convinced the wiring block will even take 10 gauge lugs. The wiring left on the back appears to be 14 gauge (eyeball calibration, accuracy not confirmed), the wiring in the panel where I checked the motor voltage also appears to be 14 gauge. Wiring diagram I have doesn't appear to have gauge specified. Comments?

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    Quote Originally Posted by Shiseiji View Post
    The accompanying document specifies 10 gauge wire for connecting to the main. So I diligently ordered some and a panel that can handle 10hp. Panel arrived so I started mounting it and placing the converter so it can be wired up. Surprise! When I opened the static phase converter everything is wired up with 14 gauge! Still shaking my head. Not convinced the wiring block will even take 10 gauge lugs. The wiring left on the back appears to be 14 gauge (eyeball calibration, accuracy not confirmed), the wiring in the panel where I checked the motor voltage also appears to be 14 gauge. Wiring diagram I have doesn't appear to have gauge specified. Comments?
    There is a phase converter forum, so you would probably get better answers there: https://www.practicalmachinist.com/v...rters-and-vfd/

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    It never hurts to use a larger than necessary wire. How much amperage you pull depends on if you max out the converter or run conservative. Keep in mind that the two conductors for the mains handle all current and the secondary three phase splits that current between three wires. Also the individual wires in the photo are short and have a lot of air space around them.

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    Quote Originally Posted by Shiseiji View Post
    The accompanying document specifies 10 gauge wire for connecting to the main. So I diligently ordered some and a panel that can handle 10hp. Panel arrived so I started mounting it and placing the converter so it can be wired up. Surprise! When I opened the static phase converter everything is wired up with 14 gauge! Still shaking my head. Not convinced the wiring block will even take 10 gauge lugs. The wiring left on the back appears to be 14 gauge (eyeball calibration, accuracy not confirmed), the wiring in the panel where I checked the motor voltage also appears to be 14 gauge. Wiring diagram I have doesn't appear to have gauge specified. Comments? ...
    Unless the motor/generator wiring has been replaced, it's #10. How are you determining the gauge of the wire?

    You definitely want #10 wire for a motor/generator 10EE. The AC section of the MG draws about 100A for the first second or so as it's spinning up, that will pop a 20A fuse. You need a 30A circuit and should use 30A fuses at the disconnect on the back of the machine. Remember, the fuses and circuit breaker are there to protect the wiring in case of a short circuit. The overload device on the main AC contactor is what protects the MG from drawing too much current.

    Cal

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    Quote Originally Posted by Shiseiji View Post
    The accompanying document specifies 10 gauge wire for connecting to the main. So I diligently ordered some and a panel that can handle 10hp. Panel arrived so I started mounting it and placing the converter so it can be wired up. Surprise! When I opened the static phase converter everything is wired up with 14 gauge! Still shaking my head. Not convinced the wiring block will even take 10 gauge lugs. The wiring left on the back appears to be 14 gauge (eyeball calibration, accuracy not confirmed), the wiring in the panel where I checked the motor voltage also appears to be 14 gauge. Wiring diagram I have doesn't appear to have gauge specified. Comments?
    Fusing Currents versus American Wire Gauge for copper, aluminum, iron, and tin (Cu, Al, Fe, Sn), wire melting currents

    Bare #14, free airflow, rated to not "fuse" (melt or vaporize) until at or over 166 Amps. Insulation on it traps heat, drops that figure.

    But your starting inrush is short.

    So it should survive long enough to demonstrate that a static "converter" does not.

    Convert.

    It uses capacitance to trick a 3-Phase motor into running on all it actually has.


    One phase.

    The other two are still "not THERE".

    No surprise it starts to go pear-shaped above one-third load?

    Now and then folks try for more than a third. And now and then that fries a motor.

    PITA enough when it is a European motor.. (my Cazeneuve lathe).

    Worse when it is a harder to find 10EE MG?

    Do keep us posted.

    Possible replacement used MG's units come on the market only now and then.

    The steps for grabbing yerself an IDLER motor and converting that box to a controller FOR a "Rotary Phase Converter" .. which DOES actually "convert"...- and good for 90%-or so of nameplate, even -- should be RIGHT IN that static maker's own manual?

    Or free for the effort of a download.

    The box bought you very nearly ALL of what you need.. besides a(ny) functional AC motor ... of around 7.5 HP or so. A 10 HP idler is sweet at running a 10EE's MG, for example. And/or whatever else you have with a similar need.

    That maker's "how to". ELSE.... "right here, On PM".

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    First thanks.
    • Rimcanyon - Appreciate the pointer

    • Superbowl - Wire gauge & safe not sorry - yep, Air gap - got it.

    • Cal - Need to listen to myself repeat - "I do not have calibrated eyeballs" & eyeball calibration = dead (me or machine)

    • Thermite - Static vs. Rotary - |Good|Quick|Cheap|


    Thermite, do I respect your opinion? Very much. I have no desire to have to replace the MG.
    Do I also respect what others have said about static converters? Yes.
    Do I as someone who stumbled into the 10EE plan on turning anything that will challenge the ~ 65% de-rated HP? No and that was part of the |Good|Quick|Cheap| analysis.
    Do I need to re-think this? Possibly. I don't have to be in a hurry, the people who are pushing me to get it running won't be bill payers if anything goes bad. Going to see what's been discussed on the other forum and price motors for a RPC.

    Ron

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    I would add oversize on the incoming side is not all bad as it prevents voltage drops during transients. Recall all electrical events are not static-steady-state and are dynamic (not directly applicable but think of striking an arc).

    If the wire won't fit I suggest using ring terminals with a #10 screw and #10/12 lug. Typically with yellow insulation.

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    Quote Originally Posted by Shiseiji View Post
    Static vs. Rotary - |Good|Quick|Cheap|

    ... price motors for a RPC.
    "Generally".. adding a 3-Phase motor as idler to a "static" converter and creating a "Rotary" with FAR better performance is sooo easy.... that the only 'real' barrier is transport cost of the idler!

    Even if... the idler is UNDERSIZED? Such as a 5 HP idler where 7.5 HP or better would be the recommended size for a 10EE's MG?

    It will be far better than a "static" alone. No mystery to it. 10EE HAVE been run off static. They do not compare well.

    You already have most of the "spend" in the static's box. "re-purposable".

    Not hard to enhance it with a "borrowed" motor to "suck it and see."

    One of mine used the motor still mounted INSIDE OF a medium-sized mill as an add-on to boost the starting power.

    All I had to do was run three wires and try it out to turn a 10 HP RPC into a 15 HP one.. to start a DIFFERENT machine.

    THEN I went and bought bespoke idlers.

    Each needed a contactor. I put the run/balance caps on the idler-side of the contactor so it "auto-sizes" as I pick and choose which one(s) to activate.

    But the original 10 HP Phase-Craft starter/control box did NOT need anything more. It only has to start the FIRST one. And the original 10 HP is the largest.

    Should be much the same with the box you already have.

    Check the maker's pubs!

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    Shiseiji,

    There are a number of members here, including Bob49 (link), running motor/generator 10EEs from "static converters" and they are working out just fine for them. Since you have it in hand, go ahead and give it a try.

    As Bill mentioned, the typical "static converter" is just the motor starting part of a rotary phase converter and consists of a potential relay and one or more starting capacitors. Once the motor starts, the potential relay disconnects the starting capacitor(s) and the motor limps along on two of the three phases, thus 2/3 power.

    However, there are electronic static converters on the market (NOT including the top of the line Phase Perfect units) and those can be a problem. A member here had one fail and do some damage to the machine, so I would steer well clear of those.

    If you have the potential relay type converter, you can improve things by adding run capacitors between the real phases and artificial phase. To do that, you need a clamp-on ammeter so that you can measure the current flowing in each phase and adjust the capacitors to balance it. Let me know if you want more information on that.

    Cal

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    Did you read about the Steelman Method? I think there are Two stickies on the topic, and it would allow you to run the MG at fullly rated power, strictly on single phase power, no phase converter needed.

    Single-phase Power for Motor-Generator 10EEs

    Converting Monarch 10ee motor-generator 3-phase to single phase, Steelman method

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    Quote Originally Posted by Cal Haines View Post
    ....Once the motor starts, the potential relay disconnects the starting capacitor(s) and the motor limps along on ^^^ the ONE AND ONLY phase winding you actually have at full normal power.
    .. plus 'extra' energy taken from that one and only incoming phase upstream feed and ....delayed a skosh AKA "phase shifted" by just enough to partially-power BOTH of the TWO missing phase windings.

    The other two do NOT have "full, normal, power". Rough running under load, uneven heating, and chattering or trip-out of relays and protective gear is the reported symptom.

    That's been in PM's files - and not-only - for long years, already.

    They have just enough partial power to keep the DIRECTION of rotation stable and reduce lumpiness as the motor turns.., so long as.. not ASKED to produce much more than one-third power.


    .two of the three phases, thus 2/3 power.
    Sorry. NOT SO! ONE phase is all you have to work with, not two.
    Wire-count is not Phase-count.

    Passive lumped reactance only "fakes" a Phase, it cannot provide full power.

    - An RPC is NOT "passive".
    - A Phase-Perfect is HIGHLY "active"
    - As are VFD.

    Reliable loading for a "static" is around 31 % power, given imperfections. Not-even 33 %.

    A portion of the one phase you DO have is being tapped to help cover the missing two.
    It only "appears to work OK" whilst operated at very LOW LOADING!

    Which DOES exist. Some cases it is even all the time.

    That's WHY we have folks claiming it works OK!

    More honest to report it "limps nicely enough ... if you are gentle with it?"

    My age? I kinda resemble that slow limp performance meself!

    A five minute 20 second mile in jump boots .. or 12 miles in full battle-gear at a dead run ...carrying an M-60 ... is getting awfully close to 60 years in the rear-view mirror!


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    Quote Originally Posted by rimcanyon View Post
    Did you read about the Steelman Method? I think there are Two stickies on the topic, and it would allow you to run the MG at fullly rated power, strictly on single phase power, no phase converter needed.

    Single-phase Power for Motor-Generator 10EEs

    Converting Monarch 10ee motor-generator 3-phase to single phase, Steelman method
    Yes, I did, thank you. I decided it was more than I wanted to do not knowing the condition of everything else.

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    A five minute 20 second mile in jump boots .. or 12 miles in full battle-gear at a dead run ...carrying an M-60 ... is getting awfully close to 60 years in the rear-view mirror!
    Cold War Soldier. '82 in the 2nd week of OCS Army decided to stop running in boots. Mostly. What I think about more now is running in boots and a M-17 and hoping I never had to do it for real. Now I'm biting my tongue really, really hard.

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    Quote Originally Posted by Shiseiji View Post
    Cold War Soldier. '82 in the 2nd week of OCS Army decided to stop running in boots. Mostly. What I think about more now is running in boots and a M-17 and hoping I never had to do it for real. Now I'm biting my tongue really, really hard.
    One of the FUNNIEST, ever, "head games" that young lootenants play, was a BET amongst we "Black Hats" over whom had the fastest runner as a Cannibal.

    The money is put down. The race is on. One OC just flat out VANISHES ahead of all others!

    One of the losers says:

    "Jesus C****T! Who TF does that guy think he IS? Mel Pender?"

    The Tac who had sandbagged the lot of us replied:

    "He actually IS Mel Pender. He THINKS he is going to become a Combat Engineer Officer."

    And Mel did exactly that. Commissioned into "the Royal" Engineers as some called us!



    Not all that young at the time, actually. Mel had already served quite a while as a damned fine Sergeant.

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    I was a SP4 with an "attitude" (not really, but makes a better story) who really just wanted to go to flight school and someone thought they were helping me by telling me to earn a commission first. So off to Benning I went . . . and that journey turned out nothing like I could ever have imagined. Some of my most enjoyable times were BSing with Sr. NCO and have one look at me and almost not as a question "You were a trooper, weren't you?" Followed by troops quietly telling me "thank you." Or, LOL, asking me, in the field, for a tool they just knew if anyone had one squirreled away, it would be me :-) Respect and willingness to follow orders is generally earned, not appointed from on high. Will never happen, but I'm a believer that every, ESPECIALLY US Officers, must spend two years "in the ranks" and get a recommendation from both their commander "and" Sr. NCO to even apply. Living in "real" open bay barracks takes the edges off most. As well as an appreciation for really stupid orders that just maybe were "poorly communicated." Anyway, thanks for sharing some of your history.

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    Quote Originally Posted by Shiseiji View Post
    I'm a believer that every, ESPECIALLY US Officers, must spend two years "in the ranks" and get a recommendation from both their commander "and" Sr. NCO to even apply.
    LOL! For several months, I was on E2/E3 pay.. an Artilleryman.. the only "green uniform" in a room full of blue.. filling a NORAD Field-Grade command slot.

    "Deputy Battle Staff Commander, BUIC II, NYADS, NORAD" .. actually made more money off a side-gig... cleaning a five suite BOQ bedding changes to toilets.. and keeping the O'Club STRAC and bar glassware crystal sparkling ..

    ...than he was paid to control the entire NYADS arsenal of NIKE HERC and their W31 warshots!



    Later-on... three of us "1LT" leaving the O Club after a lunch at Long Binh.
    I had snatched the tab and paid it, saying:

    "It's only fair. I am paid as much as you two put together."

    One of the others said thanks, but that's comical. "All 1LT's are paid the same."

    "Really?

    "O2-over-3"..... due to my enlisted "RA" time ...puts me @ $881/month.

    Sure enuf'.. they were each straight out of ROTC, just over a year of active, and were indeed on just about exactly HALF that!

    WTF would THEY know about cleaning toilets... or committing 20 kT W31 warheads?

    Army had a need? They put what they HAD to filling it.
    Not what they only WISHED they had.

    "Run what you GOT!"


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    My 7 years in the reserves gave me a nice time in service run, 20 on Active = 27 total for pay.

    "Run what you GOT!"
    One of the few things Rumsfeld hit right. "You go to war with the Army you have, not the one you wish you have" I think many people would be shocked that in 2007 we were managing aircraft by individual tail number getting them out of refurb for deployment with just days to spare. Not like the days when Huey's were more easily replaced. Don't miss that !#$% at all.

    Ron

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    Just trying to be simple here. when going from 3 phase amperage to single phase amperage one must multiply by 3^(1/2) or square root of 3 so 15 amps time that is 26 amps hence ten gauge wire.

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    Quote Originally Posted by madmachinst View Post
    Just trying to be simple here. when going from 3 phase amperage to single phase amperage one must multiply by 3^(1/2) or square root of 3 so 15 amps time that is 26 amps hence ten gauge wire.
    Thanks. Little formal training, I have to question and be pointed to how to learn the correct answers.

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    Quote Originally Posted by Cal Haines View Post
    Shiseiji,

    There are a number of members here, including Bob49 (link), running motor/generator 10EEs from "static converters" and they are working out just fine for them. Since you have it in hand, go ahead and give it a try.

    As Bill mentioned, the typical "static converter" is just the motor starting part of a rotary phase converter and consists of a potential relay and one or more starting capacitors. Once the motor starts, the potential relay disconnects the starting capacitor(s) and the motor limps along on two of the three phases, thus 2/3 power.

    However, there are electronic static converters on the market (NOT including the top of the line Phase Perfect units) and those can be a problem. A member here had one fail and do some damage to the machine, so I would steer well clear of those.

    If you have the potential relay type converter, you can improve things by adding run capacitors between the real phases and artificial phase. To do that, you need a clamp-on ammeter so that you can measure the current flowing in each phase and adjust the capacitors to balance it. Let me know if you want more information on that.

    Cal
    Cal, a belated thanks. I purchased the SPC based on a comment you made, but hadn't found the orginial posting. Probably because it is in a VFD thread. I wired the SPC up today, nothing. Not a even a flash on the panel. Have confirmed the 240 to the SPC, the first troubleshooting step is to swap two of the legs. Going out to try that.

    I've also purchased a RPC, was supposed to be here today, maybe tomorrow. One way or another, hopefully I will get it to spin soon.

    Ron


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