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Active Contributor

Join Date: Apr 2007
Posts: 23

Medium Voltage Generator Connectors

11/02/2007 3:37 PM

Hello All....

I am looking for a way to provide connectors (perhaps cam-type devices) for a 2500 KW medium voltage (4160 volt) portable generator. The same way you would provide a "generator receptable" for a 480 volt generator. I am anticpating six (6) parallel sets of conductors.

Are there such devices out there? If so what is the brand name or website?

Thanks for all the help (this is in the USA, by the way)

badski

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Guru

Join Date: Aug 2007
Location: Indiana, USA
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Good Answers: 61
#1

Re: Medium Voltage Generator Connectors

11/02/2007 5:53 PM

CSM Eng has the right idea. The devices are called separable connectors, and there is an industry standard to the design. That means that any manufacturer's elbow will work with any other manufacturer's bushing, as long as they both conform to IEEE 386.

I have to ask: Why 6 conductors/phase? Even at a lousy 0.8 power factor, you're still only talking about 430 amps. More parallel conductors means more chances for a bad connection to reduce the load on 1 cable to cause a domino-effect overload on the others. Rather than using six AWG #4 or #2, I would recommend two 4/0 per phase, or one 500 MCM per phase.

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#2

Re: Medium Voltage Generator Connectors

11/03/2007 9:10 AM

PR2THEPEOPLE is pertinent: why 6 cables per phas for only 430A?

Aren't you missingthe sqrt3?

Anyway, a good solutio, even when you actually have large ammounts of currents is to use a busbar or a set of busbars.

Regards

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Power-User

Join Date: Jul 2007
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#3

Re: Medium Voltage Generator Connectors

11/03/2007 1:31 PM

I marketed and later re-designed such a laminated connector for a gentleman in Florida. It was called the "G-Plug".

Each layer of laminated Beryllium Copper could easily handle twice the voltage each plug was rated at. When the connector was tested at 9 UL laboratories, it passed EVERY test, including the FIRE SAFETY test, which no US manufactured connector was able to pass, at that time.

Dr. G went further and proved his connector set the standard by which all high voltage round pin and sleeve connectors should be tested, by using an articulating probe, similar to a child's finger tip, where one inserted the fingertip, to cause a fault and short the circuit, into the female or hot side of any connector.

The "G-Plug" connector passed with flying colors. No medium or high voltage, round tip, pin and sleeve connector can pass this test, for the surface area of a pin and sleeve unit must be large enough for the voltage spikes, or the units burn out.

Brass, unfortunately, requires an extra large diameter pin, as the efficiency of the internal contacts, tend to lose "grip" over time. unfortunately, machining Beryllium has a negative effect on the liver. It cannot be made round easily and therefor is MUCH MORE EXPENSIVE than the G-Plug, ever would be. Do not machine B-Copper!

EBB, Union, Maltric and Hubbell make plenty of round pin designs, but none are safer and cheaper than the "G-Plug".

Basically, pin and sleeve connectors have been obsolete since this test, over 8 years ago; yet no US manufacturer will discuss, under non-disclosure, the details of G-Plug's entry into their manufacturing inventories.

General Motors and GE have specific preclusions to signing any such disclosures, so they cannot even look at such devices, under corporate regulation, unless, of course, you don't need a non-disclosure signed. Then and only then, will everyone take a look.

Nice ethical bunch.

The G-Plug was much cheaper and far safer than any plug in it's class, in the entire world. We tested a one hundred amp G-Plug, at 5 times the rated voltage. It burned the wires beyond recognition and then was easy disconnected and used again for further testing.

Keep in mind, it was very inexpensive to manufacture, as well. High and low voltage power could have sat side by side in between the laminations, quite nicely. It would have been perfect for electrically charged battery systems which use a low voltage metering system, during charge. Say for.....Electric Automobiles!

We went on to prove the "G-Plug" to be: "The single connector which would meet, (then written and unenforced), Federal fire-electrical-safety standards", should they be enforced on a national level, here in the USA, during 1997 and the years afterwards, when I marketed the connector.

The US ELECTRICAL FIRE SAFETY CODE is quite explicit and so I wrote to several members of the CENELEC committee, who had designs on standardizing the electrical code of the EU. (The joke was on me, as it was not intended to be enforced).

I guess we weren't ready for that, at the time. The round pin people were very disturbed to find out the fruit of their labor obsolete. (Funny, how they are still manufacturing nearly every single unit they made then...).

To date, I know of no distributed electrical connector, manufactured to the specifications "Dr. G" designed to, nor the advanced design which I put on the table, where the connector was improved to be explosion resistant and capable of deep sea salt water resistance.

I don't think "they", (the collective industrial "they's"), liked it when I pushed the designs further and offered a rental unit to seal and re-insure the explosion resistant connector, either. (Dr. G didn't, that's for sure).

Similar to the Torsion Control Bolt System, (or T-C Bolts, used in Iron Work connections), you would have to rent my apparatus, in order to "seal" these explosion resistant electrical connectors. (My Grandfather worked with Mass Mutual to bring us out of the dark ages of rivets during the building of the first US Turn Pike, so I had first hand knowledge of methods employed to re-insure such important connection systems. Every Torque Gun used for T-C Bolts, must be certified by the patent holder of the bolts, (the insurance company), prior to use on any structural steel framed building, in the USA). So I emulated that train of thought; (quite unsuccessfully, I assure you).

In similar fashion, the connector would have been be re-insured via the constant setting and resetting of the system and the rental unit, to force compliance of standards and re-evaluation of the devices by a certified and alter-insured group, further deliminating the risk and insuring the rental systems were of best quality, at all times. (We wouldn't want things to blow up, now would we).

You see the shape of the connector "Blades" is where the patent comes into play. It was impossible to defeat the rotary action of the connector and cause a spark. Therefor, it was impossible to cause a spark or fault via plugging in the male and female connectors, and therefor it was allowed the patentable statement;

"non-defeatable, rotary, sequential, circuitry"

It seems Dr. G was none to thrilled to find out his apprentice eclipsed his designs, before he could even get them manufactured, after I discussed the details of the explosion resistant system with him. (He never got over it, even though I tried to share the concept with him equally. My guess is, he had other ideas for any revenue earned, than sharing any with me. I was just the dope who he would use to market the connector and he would keep all the money).

We both remain nearly broke, to this day, for attempting to introduce such quality on the world. (I wouldn't recommend you follow in my foot steps).

I suggest you use cheap brass pin and sleeve connectors, like everyone else. They break all the time and cause oscillations, which wear out the voltage regulators in your system, right on schedule. Then when they weld together, and they eventually do, unless you spend more money for switch grade connectors), you can take a hit with your insurance, when it hurts someone.

"We", (the collective industrial "we"), are not ready for the standards to reflect true compliance. (...and "we" aren't "paying" for any new ideas, either; because it's more fun to "borrow" them and let the foolish designer or engineer, sue for his end or run the course of what pathetic systems we now manufacture).

Good luck with your search.

I'll be hanging out with Stinky Pete the rest of the afternoon.

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#4

Re: Medium Voltage Generator Connectors

11/04/2007 11:49 AM

Thanks for all the help. I looked on the ABB website (as indicated by CSM Eng)...and noticed that they are rated as 15 KV. Is that the lowest rating before you go to 600 volt? Do they have them in 5 KV rating?

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Guru

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#6
In reply to #4

Re: Medium Voltage Generator Connectors

11/05/2007 2:26 PM

Elastimold makes the same connectors in 5 KV. You can also get the same connectors with additional functionality, such as built-in surge arresters, fuses and voltage or fault detectors.

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Power-User

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#5

Re: Medium Voltage Generator Connectors

11/05/2007 1:21 PM

The smaller Tweco connectors, originally specified for welding ground, with the rating you are seeking; have been removed from inventory because they are all too often improperly used and the heads are too heavy for the gauge wire they are specified for.

Repeated use will break over 50% of the copper strands, because of the weight of the brass.

We used them for film lighting systems and they would cause fires throughout the studio, when the frequency oscillations would cause harmonics in the generators. Once they overheat it becomes impossible to bear the connections and there is usually no method of laying the wiring in such a fashion it will not cause an ohm load.

The Union three pin connectors fail the same way, melting the Bak-o-Lite, when a leg becomes overheated or welded together. (They are allowed to stay in service, anyways).

When faced with the child's finger device, these Goliath's of manufacturing just add a massive chunk of spring loaded CAP or screw threaded cover, which breaks off, or is very difficult to work around and requires constant repair, as a solution to the inevitable; a major accident via fault. Try unscrewing a six inch chunk of plastic while your friend is being eaten by the tire machine.

Miller Electric manufactures there own proprietary line of welding connectors, as they cannot use Tweco's anymore either. They cannot be used for generator wiring, legally.

I'm not aware of anything which will serve your needs which is of quality.

The key to Dr. G's system was distributed circuit breakers.

He holds the patent for this innovation, as well.

The G-Plug is designed to use in-line GFI blocks, which are manufactured as small as a breaker and connect between any two G-Plugs, so an LED verification can be seen for temporary or portable electrical systems and the GFI can be reached easily, close to the failure point.

We used the model of the large factory, where the tire machine is eating an employee and the premise; the ground connector is weak with a welded leg, inside the plug. Imagine having to run the entire length of the factory, because the connector will not un-plug, just to hit the breaker, in a box within a locked wire cage.

Or worse, the breaker is also welded closed or broken from years of continuous use and zero maintenance.

Needless to say, this happens all the time and can be resolved with quality connectors and small, unobtrusive, in-line GFI QUALITY circuit breakers. the problem is the cost of manufacturing round pin systems becomes extraordinary, as they cannot be retrofitted without great expense to the end user. Round is old and outdated.

Why then, would this be a problem, you may ask?

Because the large steel box and the current system of cheap breakers would become obsolete. Your power would be a female G-Plug, say 600A. It would break out with a local box of G-Plug GFI breakers and smaller rated cables. They would, also break out into smaller amp service and the farthest anyone would have to walk to flip a breaker is 100 feet, up stream of the machinery, for 100A service and more likely 25 feet for a 20A mechanical power source. NO STEEL BOXES NEEDED.

The G-Plug is also "SWITCH GRADE", which means it can be used as a switch to turn on and off high voltage machinery, if necessary, without chances of voltage arching, as you approach a connection, between the pins of the connector. You can also use the handy circuit breaker, which is near by or in line, so a person 300 feet away can just trip the breaker next to themselves and stop the entire problem.

It's quite detailed, once you understand the process of fault and how much money we dump into out dated systems, just to keep using the same old basic service, designed forty years ago.

It's rather amazing how insurance companies can fold a company with unbearable cost of insurance, or overburden the consumer with expensive electrical upgrades, yet the systems which would lower the cost are not allowed to be manufactured by the very same people.

I cannot imagine many of the "engineering members" of the IEEE, are satisfied with the situation either. Rather frustrating, once you know there is a solution, but it will not be employed because of blatant ignorance.

My two cents.

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Anonymous Poster (1); jjbadski (1); Moto (2); pwr2thepeople (2)

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