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Parker/Eurotherm 514C/507 4Q SSD DC Retrofit into 1961 10EE Modular

Curious, what is the need for duplicate pictures. The PDF is clear for me.

Photobucket. . . Where possible I prefer having pics or attachments directly on this site to limit destroyed info. If this site folds, well its all gone. But there is a number of outside sources that have left dead links, or wiped pics. Anything attached directly here will last as long as this site and its back ups.
interesting, i never noticed that the edit ability was time limited... why is that?
i guess i'm a regular user.

Relational Database-driven website. tying to be bent into the workload of an object rather than relational structure. Z-Server/Medusa natural role.

Indices need rebuilt periodically.

VB itself SUPPORTS infinite-time editing. ISTR Jaguarforums.com runs with VB that way.. or used to do.

But PM's has a higher rate of change and greater active user load. And it ain't Object/Relational heavy-lifter PostgreSQL under it. Fragile MySQL + InnoDB kludge, rather.

The good news is that a Moderator can edit indefinitely.
Can you provide the part number of the boost transformer you used in your setup?

Covered in-thread, that Mark HAD the goods, so re-purposed the OEM one from his Modular drive 10EE, added a smaller, dirt-common transformer paralleled on the primary across 240 VAC, series at the secondary to sum for a higher Voltage.

I had NO existing transformers, acquired "many". ended up using several that can work:

Goal was the same. To derive 310 to 350 VAC into the SSD Drive

- US-built Jefferson Electric 5 kVA 411-0111-277 order Code N0706.
Taps @ 277, 270, 263, off nominal 120/240 VAC primary.

- Canadian-built Hammond 120/240 16/32 VAC @ 32V joined it.

- Federal Electric 120/240 to 12/24 @ 24 V.

Then a harder-to-find 120/240 24/48, the only one bought new IIRC.

277 + 32 + 24 + 12 = 345 VAC nominal

My done-with-experimenting only three:

277 + 48 + 32 = 345 nominal.

Annnd I may yet get down to just two!

There are LOTS of combinations that can get to 300 - 350 VAC


kVA size when in such an array is proportional to Voltage of each as a percentage of share of total Voltage.

Total capacity around 5 to 7 kVA is plenty.
I just checked again, I did misremember. I measured 310 volts, this is from the Monarch T5 that EverettEng thankfully gave me. I have had no issues with power to the motor and the 230 VDC output. But then who knows the accuracy of my multimeters. I have a Triplet modern (Chinese) and a 1970s Radio Shack (USA). Won't bother mentioning the multiple HF digitals I throw around in the household toolbox.

Here are my "Parkers in a drawer" pics. I don't need the 240/120 transformer any more, I was using it for relays before I changed my ELSR switches to DPDT. The timer relay will work on 240 volts, I just didn't bother to remove the transformer when I removed the unneeded relays.

Yeah, I know it isn't to code...


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I just checked again, I did misremember. I measured 310 volts, this is from the Monarch T5 that EverettEng thankfully gave me.
Serendipitous in that it is the SAME transformer.

If you and Mark would compare readings, and with which meter observed, of your respective utility mains "nominal" 240 VAC split-phase power, I think that mystery will be solved.

Ex: My VEPCO / Dominion VA power feed was 245 VAC around 25 years ago, 246 VAC when I began my SSD experiments, and still is. Fluke 77, and cross-checked with three other meters.

That means my nominal 240 <=> 277 Jefferson Electric lighting transformer actually measures higher than nominal output side. "And so on" as to the nominal vs actual for the rest of my array of transformers.

I have had no issues with power to the motor and the 230 VDC output.

Not sure how much it matters if you guys each have the "S1, S2" series compensation leads to the electromagnetic boost load-sensing that all of the 5 HP and the 3 HP "small frame" motors had available?

Whether put to use or not?

The MG-era 3 HP "large frame" 3 HP OTOH, was wound straight shunt, has no such boost coils of its own.

It relied on the equivalent off the load-sensing series coils in BOTH of the MG's exciter and DC generator to boost the Armature Voltage output as Armature current draw increased under load.

My substitute for that was to make "available" the higher limit of 275 VDC in the SSD's settings and my ~ 350 VAC transformer array.

It doesn't actually call on that higher Voltage, ordinarily, but it is "there if it needs it" to keep RPM up under load.

Same again the use of boosted 140 VDC for the Field instead of 115 VDC.

"There if it needs it" reserve, extended low RPM grunt, accel and - most often useful of all - nice, fast regenerative braking.

The bottom line? Time having passed, and even the oldest of solid state drives having proven their merit:

- For best stability under load, high RPM, Field Weakened range, the single-phase packaged DC drives need about 10% to 20% higher AC input than the thermionic valve WiaD or Modular drives needed.

- A ripple filter wasn't as essential on WiaD or Modular either. In THEIR case the power transformer's inductance was "inside" the overall circuit rather than outside of it.

Three-phase input DC Drives - favored by the factory and "deep pockets" DOD depots and DoD or private aerospace contract upgraders, never were hard:

OTHER THREADs have, and will cover those:


Monarch Sidney DC Drive. Monarch's own, (with third-party helpers), but seldom seen.

Sabina (one of the oldest, 1969 design, still supported, still in production, brand-new, and may yet prove to be the least-cost to maintain and most long-term durable 10EE drive known since the MG?)

Saftronics (part of Nidec, now?)
GE Valutrol
GE DC500 series
Control Techniques, Mentor & not-only (also now a Nidec property, no longer Emerson)

Several others... Fincor - a modified single-phase drive? .. also still in new production.

At the "economy" end?

180 VDC out single-phase drives that cannot work with a boosted AC input don't exactly "fail", either.

However.. unless. .also paired with a motor wound for 180 VDC (many of mine)... they just fall down at about half of nominal power off the back of abysmal load regulation. Lacking full Armature Voltage capability, they must run deeply into Field Weakening even to reach "base" RPM, thereby seriously robbing the motor of reserve torque.

Unfortunately, matching a motor is not as easy as buying one. 180 VDC wound DC motors are a great deal heavier than 230 VDC wound, same power. They are also generally too large to fit into the available space @ same power.
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All this talk for years about a proven failure using off the shelf drives to replace the modular drive!
It may turn the spindle, but in real life it does not hold up, it does not perform, it is a colossal dud dreamed up by one individual that does no actual work at all on the Monarch 10ee.
Show us, once and for all, demonstrate this dime store, and bailing wire stacked drive, with ripple filter on video, doing full function!
I will not hold my breath waiting for that!

Come on experts, show the factory how to do it.

The silence is deafening! Why steer people to such a pile of crap when many have had better luck with VFD conversions?
Yes! Someone had to say it!
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