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    Default Another DC Drive Thread

    So I think I've read most of the DC drive threads, but I'm still trying to understand the basic controls used during a the Parker 514C conversion.

    My WIAD drive is long gone, so all I have is the small frame motor.

    Can the Parker 514C, provide braking when the run is turned off (i.e. the ELSR handle is switched to the stop position) while the speed control remains in the same position?

    Has anyone developed a single knob speed control that controls the armature to full speed then starts reducing the field? I'm not interested in having two pots tied together with weed eater string.

    Does the Bardac 3600XRi/32LL and the Sprint 3600XRi/32LL have the same configuration / control restrictions?

    The reason I ask about the Bardac and Sprint is that they seem to be available within the US, Most of the Parkers have to be shipped in from the UK or China (Ebay). Has anyone actually bought one of the Ebay Parker 514C from China?


    I look forward to your comments / experience.

    jdub

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    Quote Originally Posted by Jdub63 View Post
    Can the Parker 514C, provide braking when the run is turned off (i.e. the ELSR handle is switched to the stop position) while the speed control remains in the same position?
    Yes "but" . .with some modifications:

    1) A "4Q" DC drive has no braking resistors and does not need them, but ENABLE and RUN have to remain true so the 4Q "regenerative" drive's control logic can selectively fire its SCR's to manage the ramp- up or down to the target RPM - or full stop - that you command.

    2) What can work is to transfer the control from - call it the "primary" - speed/direction pot - the one you said you do not want to move from its setting - to a fixed (or ten-turn fine adjustable) one that has been tuned to some workable resistance to balance the "at zero" value, then left alone.

    ISTR Everettengr did "something like this" with a small relay - and covered it in his thread?

    He had also discovered an undocumented feature wherein the SSD drive can be caused to do a sort of "reset" that was found to be very useful.

    NB: He retained the ELSR function, as you are (apparently) seeking to do as well, so will be your better source of guidance as to how to integrate the existing ELSR controls ... and a modest bit of add-on.

    I simply remove ELSR as a distracting annoyance on my machines! One control is simpler for me, and it isn't involved in "away" threading anyway.

    See also the manual in re the "at zero speed" / go to zero-speed control/signal optioning.

    One can extend the usefulness to implement "Field economizing" so as to shut-off the Field power altogether once the spindle has come to rest. It is not uncommon to do this to reduce heating in DC motor applications whilst idle. It isn't really required for the 10EE.


    Has anyone developed a single knob speed control that controls the armature to full speed then starts reducing the field?
    Easiest is to just use any of the Monarch OEM ganged ones.

    The BIG ones, MG-era, have a very poor match to value in Ohms, ergo draw a lot more current from the drive...but will WORK.

    The smaller ones, Modular-era are better.

    The SSD specs 10K Ohm linear, but the signal line presented to the wiper is low Voltage and low Current with current-limiting back of its source, so doesn't actually much care.

    That will want the change to single-ended control with reversing done by a separate switch, not the FWD-BRAKE/OFF-REV single-knob default.

    ELSE.. wire-wounds modified at BOTH ends, which can be done, but would be sore TEDIOUS. Hence my preference for multiple linear sliders wherein the modifications are to a mechanical plate, not to the electrical goods.

    For "one-offs" not mass production, one modifies stock goods for this sort of use by shunting the turns of resistance wire for a portion of the travel on a wirewound pot with foil or wire soldered at the outer vertical edge, clear of the moving wiper up on the flat.

    That section will then have the same resistance for any position within its portion of travel. You would want roughly half, and opposite half zones for Armature control and Field control.


    Does the Bardac 3600XRi/32LL and the Sprint 3600XRi/32LL have the same configuration / control restrictions?
    Haven't done a deep-dive, but they are nearly identical goods. Photo of the Sprint branding seems to have the same eight-count of firing inductors as SSD's have, might be the smoother runner, whereas the Bardac photo shows but four?

    That might actually just be two different models chosen to take a photo of, though?

    Not overly fond of either, but their manuals show much the same capability set as the SSD, so "stuff needs to be researched and addressed" might be more accurate than "limitations".

    ISTR others HAVE applied these to 10EE, so maybe you can get some help if you go that route?

    Not to forget that the second section of the variable-resistance control isn't involved with the Armature drive in either case. It is controlling a separate Field Supply source.

    Getting back to ONE variable-resistance that does both is where the 3-Phase-only DC Drives with onboard Field Regulator circuit operate.

    But "RTFM".

    The terminal usually connected to the "wiper" contact of an SSD's potentiometer can simply be fed a precise control Voltage from some external source.

    That source can be whatever you see fit to adapt or build from scratch.

    The Field supply DC Drive operates the same way.

    So yes, both can be controlled together, and a ganged variable resistor isn't even the only way to do that.

    ISTR some other Pilgrim is storing digital values in a Programmable Logic Controller and outputting them via DAC? Arduino's have been mentioned, too.

    I prefer to just use what the packaged DC drive already HAS, meself.

    Why pay twice or create a one-off instead of a right out of the box drop-in replaceable unit?


    The reason I ask about the Bardac and Sprint is that they seem to be available within the US, Most of the Parkers have to be shipped in from the UK or China (Ebay). Has anyone actually bought one of the Ebay Parker 514C from China?
    Why "China"? There is a Parker Dealer about 2 miles from my house. Hydraulics, mostly, but Parker's goods are in distribution channels all over the planet.

    Have you not tried the Parker website product SKU + ZIP Code search?

    NB: I doubt ANY US dealer "stocks" them. Special order and shipped-in, would be my expectation. Besides Bristol, UK, they have a depot in Offenburg, DE. Nice town, pleasant folks, and good local beer, actually.

    One can order directly from the UK. I've not had a problem getting goods from the UK in general.

    But at least if ordered through Parker, USA, even if special ordered and there is a delay, it is Parker sorting the shipping, risk of loss, damage, etc.
    Last edited by thermite; 06-04-2021 at 05:38 AM.

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    During discussions with several tech support guys, one suggested placing the stop / start control switch in series with the speed pot. This would allow the speed to be ramped to a stop. Do you see any downside to that configuration?

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    Quote Originally Posted by Jdub63 View Post
    During discussions with several tech support guys, one suggested placing the stop / start control switch in series with the speed pot. This would allow the speed to be ramped to a stop. Do you see any downside to that configuration?
    "Start/Stop" on WHICH DC drive?

    On the SSD, that would be "RUN" and even so it is only the "enabler" for the speed set potentiometer. Pot is at center of travel, on "Zero"? Nothing yet moves.

    Pot is returned to "Zero" (center of travel) spindle is braked to a halt. By the way the control logic tap-dances on the triggers of the SCR's

    And were these "guys" in Bristol, UK or somewhere less familiar?

    Most SSD drives done years ago didn't even use it's feature set at all.
    They used it as if it were an ignorant coolant pump switch.
    RTFM.

    A "switch" would bypass your ramping control. Best it can do is trigger a "reset" that simulates a "(seek) zero speed" command. That's not as good as what an SSD CAN do, but is a way to preserve ELSR with low/no hassle.

    Except ELSR isn't needed to begin with!

    Simply do the usual and thread away from a feature, shoulder, or obstruction instead of TOWARD it. How did yah figure tens of thousands of lathes that never HAD ELSR had made all of the world's decent threads for more than a hundred years before the 10EE even existed?

    See Joe Pie You-Tube on threading in reverse.

    We ALL knew how to do that. No other option on seriously LARGE lathes and stunning levels of rotating mass.

    Brake/Halt position on a Parker SSD is otherwise when the reference Voltage either externally supplied ELSE tapped off the potentiometer's wiper is at balance between forward and reverse. A trimmer can be used to adjust that to agree with a dial or pointer's center OFF/brake markings.

    It is not the ONLY way to control an SSD drive.

    Just the "default" and a very fast and "natural" one when using a Joyce-type "stick" to operate the lathe. Faster you move the control to or away from center, faster it stops or accelerates. TheFURTHER you move it, the higher the RPM.

    markings oreven mechanical detents are OK. Preset adjustable resistors are OK. Similar to a 1950's autmobile radio station presets. Same one button-down, all others UP latching switch frame can even be used. They still make those.

    A switch can only abdicate variable control to the preset ramps (there are trimpots) ...at best.
    RTFM.

    And the PCB's defaults are not very fast. 2 second @ minimum setting, IIRC?
    RTFM.

    There are also, however, terminals provided to over-ride the onboard resistors for faster braking and acceleration.
    RTFM.

    Those are presented on the loong terminal strip and the AMP cable connection for the plug-in LCD-screen "Commissioning Device". Or on the PCB itself.

    ... where the motor and drivetrain are au fait with that rapid delta?

    And a 10EE IS au fait with it?

    VERY fast on the near-as-dammit "servo" 3 HP large-frame motor.

    I can shake a can of PAINT at the chuck with the SSD drive by diddling that Voltage.

    Not that I do. Hard tasking for a high-mass motor. So it was tested, only.

    Just that it can react that fast and with that much control authority and right down to one revolution in fifteen seconds - WITH a stout "ripple filter", anyway. Recall I filter the Field power as well, AND provide up to 140 VDC even so.

    IF the "zero Command "is not allowed to be satisfied with "AT zero RPM" signal? It will hold the spindle braked in a set position.
    And push it BACK to that position if you push it off in EITHER direction.

    At one-quarter of one RPM? I lost further interest in how slow it COULD go!

    Or maybe just fell asleep?



    "On which score..." falling asleep... Everettengr is a bright guy and a trained Engineer. Just not an Electronics Engineer. BFD.

    No matter. He could read and work with the Engineering info in the manual just fine.

    He and I figure it takes FIVE reads THROUGH that manual to get back to the conclusion that of hundreds of options and nuances, all we need after all was the most BASIC out of their "library".

    That's why his thread can save you going off and turning the bugger into a coil-winder, coil spring maker, paint shaker, rotary broach .. or in my case, simply trying to fix my bustid alien landing craft to get back to the "mothership" and my own damned galaxy!

    Or so I stand accused .... on a slow day, anyway!

    Even my eye surgeon says I have "alien DNA". BFD. I thought ALL humans healed in 2 or 3 days? As we do.

    Until some negatroid tells us we "cannot".

    Go figure when we grew dumb enough to disadvantage ourselves so others could invent the health-scare racket my grandparents nor THEIR ancestors never knew they needed?

    DC Drives can be like that. Figire out what you want. Confgure it to JF doo what you want.

    Same as DIY biotech. It helps to RTFM.

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    Thanks for the input

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    Quote Originally Posted by Jdub63 View Post
    Thanks for the input
    Thanks but..

    You may come to find it initially leads to a great deal more work than it saves!

    even so..

    WHEN you do the homework to understand an SSD, not just "plug it in"?

    You will "own" the info, be able to apply it to other DC drives, too.

    Most of those are NOT "Swiss army knife flexible", as "universal donor" have FEWER options, not MORE.

    So it gets easier over time.

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    Thermite mentioned mentioned EverettEng, I think he meant me. I have the Parkers and I came up with a relay arrangement so I have full ELSR functionality, and I have approx 1.5 second brake-to-stop regardless of whether running in full field or field weakened.

    I have designed a single knob control to control two pots, not complicated, but so far I have not spent the time to make it, and it has not been an issue to me. Either I am running below 1150, or I am running above 1150, but no part so far has needed to vary in between. So the issue of turning the first pot to full, and then turning the second pot, really hasn't been a burden.

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    Quote Originally Posted by bll230 View Post
    Thermite mentioned mentioned EverettEng, I think he meant me. I have the Parkers and I came up with a relay arrangement so I have full ELSR functionality, and I have approx 1.5 second brake-to-stop regardless of whether running in full field or field weakened.

    I have designed a single knob control to control two pots, not complicated, but so far I have not spent the time to make it, and it has not been an issue to me. Either I am running below 1150, or I am running above 1150, but no part so far has needed to vary in between. So the issue of turning the first pot to full, and then turning the second pot, really hasn't been a burden.
    I've no klew who did it "first" - it has probably been done many times.

    But among the reasons it isn't a burden is that if your Armature pot is set to full, the SSD drive will automagically supply higher Voltage than the pot asked for when the IR sensors see the RPM trying to drop under load.

    That is NOT as good as a proper full-court-press "Field Regulator" circuit, but ... it is cheap and cheerful to provide the extra reserve in the choice of max boost AC inpout, soooooo .. we dooze that.

    Also why the 180 VDC-only DC Drives fall on their nose so damned badly!



    It MIGHT also explain why the immediate predecessor to the 514 XX DID have a mating Field-Regulator in a separate (and large!) box.. but SSD didn't make a new one for the newer drives.

    FWIW - the Eurotherm/Parker 3-Phase ONLY DC Drives, both Analog & Digital, DO have Field Regulator circuitry either onboard or as a plug-in option card.

    MOST premium 3-Phase-only DC Drives, any major maker, do as well.

    And.. most of those drives start at TEN HP and go up... to over ten THOUSAND HP, even.

    The big ones are not big drives. They are simply whole buildings full of rows and rows of rack cabinets networked together!


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