Third Party

Dear Alert Amphibian-

Can you provide third party data demonstrating that cable injection will extend the life cycle of underground cables? My colleagues and I are preparing for a rate filing with the OEB and we are looking for some firepower, facts and figures to bolster our case for additional cable injection monies for 2014 and beyond.

Seeking help,

Organizing in Ontario

Dear Organized-

I can think of four “flavors” of third-party data.

Flavor 1

Flavor 1 includes data gathered by third parties at the behest of a firm engaged in rejuvenation. The third party is independent, and is generally working for the technology supplier. There is an ample supply of this type of data, spanning over two-and-a-half decades. As an example of this type of data, consider Figure 3 of the paper published by my colleagues at the IEEE International Symposium on Electrical Insulation in September 2004…

New Developments in Solid Dielectric Life Extension Technology 

Figure 3 shows the substantial improvement in AC break-down performance seven days after injection at Cable Technology Laboratories. There is an abundance similar Flavor 1 third-party data. A compilation of that data can be found in the bibliography presented at the NETA Powertest Electrical Conference on March 17, 2008.

History and Status of Silicone Injection Technology with Bibliography

This paper provides 50 references including flavors 1, 2, and 3 of third-party data.

Flavor 2

The second flavor of third-party data are results reported by end-users. There have been several North American utilities that have reported their post-rejuvenation reliability over multiyear periods. The IEEE’s Insulated Conductor’s Committee (ICC) Discussion Group C30 is compiling several of these case studies as part of its efforts to craft a Guide entitled, “Extending the Life of Power Cables in the Field.” One exemplary data set was published by Northeast Utilities at the spring 2008 ICC. I have attached an excerpt of the ICC meeting minutes below. Over a nine year period from 1999 to 2007, the failure rate of the post-rejuvenated cable was 0.7% and the failure rate of the non-rejuvenated cable was 12%. Novinium’s failure rate is about half of the failure rate enjoyed with this older technology – see flavor 3.

R.Vencus. Cable Injection Program CL-P 2008.pdf (8.13 kb)

Flavor 3

The third flavor of third-party data is the overall failure rate of rejuvenated cables. Circuit owners have an incentive to report their post-injection reliability issues as they get cash for doing so! Novinium transparently publishes these statistics at …

http://www.novinium.com/Lessons.aspx

Novinium’s post rejuvenation failure rate is less than that of new cable! Check out my March 23, 2012 post, “Better Than New” to learn more.

Flavor 4

The fourth flavor of third-party data would be a Coke vs. Pepsi, side-by-side “taste test” of different rejuvenation technologies funded by electrical circuit owners and conducted by a third-party laboratory. There is good news, there is bad news, and some new that falls between good and bad. The good news is such a test was arranged by NEETRAC (National Electric Energy Testing, Research & Applications Center) sponsoring firms including: AEP, BG&E, ConEd, Oncor, FPL, Exelon, Southern Company, PEPCO, Southwire, and Snohomish Public Utility District. The bad news is that only Coke showed up for the taste test! The other technology supplier participated in the experimental design, but withdrew just as the testing was to commence citing, “Business and commercial reasons.” I will leave it for your contemplation why the other guys would not want to participate in a side-by-side test. The test proceeded with Novinium only. The news that is not bad, but not ideal is that even though the test was completed about two years ago, NEETRAC has not yet published the results in anything other than draft form. An excerpt of the draft NEETRAC report provides the bottom line of the testing:

“ … the stress at which the rejuvenated cables fail is higher than for the non rejuvenated cables: 26 kV/mm and 16 kV/mm, respectively. These stresses are taken at the 50^th percentile (median). Moreover, it would appear that the [Novinium] rejuvenated cables have a threshold for failure at 4.5 kV/mm whereas there is no threshold for the Non Rejuvenated cables."

The reported performance advantage was measured after about 18 months of accelerated aging – well beyond the originally planned twelve-month experimental plan. The electrical stress of a typical 175 mil insulated URD cable energized at about 8kV to ground is 1.8kV/mm. The treated failure threshold is 2.5-times typical operating voltages even after extended thermal and electrical accelerated aging.

Ready for any party,

Thermonuclear Frog

LIPA

Dear Felicitous Frog-

I have read a paper from the conference record of the 2008 IEEE International Symposium on Electrical Insulation (ISEI) by some folks at Powertech Labs from my home province of British Columbia. The paper was titled: “Condition Assessment of 15 kV Rejuvenated Underground XLPE Cables.” The cables in question are operated with AC, but the testing method is with DC.  Does a DC test have validity on an AC cable? The paper shows results of before-and-after diagnostic testing on two treatment methods, referred to as “method A” and “method B.” Are these results representative of Novinium’s post injection experience?

Currently,

AC in BC

Dear AC-BC:

Other frog fans may wish to review the full text of the paper to which you refer. The paper is available for a small charge from the IEEEXplore^® digital library; click here to view the abstract and full citation. The test method utilized in the paper is the LIpATEST™ technique, proprietary to PowerTech Labs. PowerTech is primarily owned by BC Hydro. The LIPA technique measures the DC leakage current through the cable insulation as a function of applied DC voltage. The 15 kV-class cables described in the paper are subjected to a negative voltage, increased in 4 kV steps of 1-minute duration, to a maximum of 16 kV. The leakage current is recorded at each step. The purveyors purport that the magnitude of the leakage current and its rate of change with applied voltage provide an indication of the quality of the cable insulation.

You asked two questions: Is the test valid and are the results representative? I provide answers to both in four parts, entitled: DC Testing, LIPA Validation, Rejuvenation Methods Tested, and Representative or Not?

DC Testing

The 2001 version of IEEE 400™, “Guide for Field Testing and Evaluation of the Insulation of Shielded Power Cable Systems,” provides some guidance and is available from ANSI. Click here to view the abstract and complete citation. Paragraph 4.2 states in part …

“Whenever dc testing is performed, full consideration should be given to the fact that steady-state direct voltage creates within the insulation systems an electrical field determined by the geometry and conductance of the insulation, whereas under service conditions, alternating voltage creates an electric field determined chiefly by the geometry and dielectric constant (or capacitance) of the insulation. Under ideal, homogeneously uniform insulation conditions, the mathematical formulas governing the steady-state stress distribution within the cable insulation are of the same form for dc and for ac, resulting in comparable relative values; however, should the cable insulation contain defects in which either the conductivity or the dielectric constant assume values significantly different from those in the bulk of the insulation [Editor: That would be all aged cable!], the electric stress distribution obtained with direct voltage will no longer correspond to that obtained with alternating voltage. … Furthermore, the failure mechanisms triggered by insulation defects vary from one type of defect to another. These failure mechanisms respond differently to the type of test voltage utilized. For instance, if the defect is a void where the mechanism of failure under service ac conditions is most likely to be triggered by partial discharge, application of direct voltage would not produce the high partial discharge repetition rate that exists with alternating voltage. Under these conditions, dc testing would not be useful. However, if the defect triggers failure by a thermal mechanism, dc testing may prove to be effective. For example, dc can detect the presence of contaminants along a creepage interface.

In the case of joints and accessories, their dielectric properties may differ from that of the cable with regard to conductivity. This may result in a dc stress distribution at the interfaces between the cable and the accessory that is very different from the stress under ac voltage. A careful examination of the system is necessary prior to a dc test in order to avoid difficulties.

Testing of cables that have been service aged in a wet environment (specifically, XLPE) with dc at the currently recommended dc voltage levels (see IEEE P400.1) may cause the cables to fail after they are returned to service (see Fisher, et al. [B23], and Steennis, et al. [B48]). The failures would not have occurred at that point in time if the cables had remained in service and not been tested with dc (see Eager, et al. [B21], and Srinivas, et al. [B47]). Furthermore, from the work of Bach, et al. [B7], we know that even massive insulation defects in extruded dielectric insulation cannot be detected with dc at the recommended voltage levels.”

In short, …

1.    DC testing does not measure the same defects to which the subject cable is exposed in its AC environment.

2.    There is little or no relationship between DC test results and likely AC performance.

3.    DC testing damages the aged cable it seeks to diagnose.

LIPA Validation

If the purveyors of the LIPA test wish to validate their test they simply need to run an experiment with a suitable control. To wit, divide a population of, say 100, homogenously aged cables into a control group of 50 and a test group of 50. Monitor the performance of the control group for future failure history. Submit the 50 cables in the test group to LIPA, and then monitor that group for future failure history. If the purveyor’s claims are accurate, there will not be a significantly higher failure rate in the test group compared to the control group and the failure rate in the subgroup of the test group that tested “bad” should be significantly higher than those of the test subgroup that did not test bad. Since PowerTech is a subsidiary of a utility with a sizable population of appropriately aged cables, it should be a simple matter to arrange such a test. This frog is unaware of any such test. Without the simple application of the scientific method the claims of efficacy cannot be confirmed by this, or any other frog.

Rejuvenation Methods Tested

Novinium can and does utilize both method A and method B. Method A is properly called unsustained pressure rejuvenation or UPR. Novinium has made improvements to the UPR method. The improved UPR method is called iUPR. Method B is sustained pressure rejuvenation or SPR. SPR outperforms UPR and iUPR by any measure of post-injection reliability.

Representative or Not?

Not – for two reasons. First, as mentioned above, the LIPA test should not be used to judge AC reliability. Second, even if LIPA were a valid test, 13 samples for UPR and 4 samples of SPR are not statistically significant.

Novinium is the only rejuvenation vendor in the world that performed a full third-party, side-by-side controlled experiment of rejuvenation technology. The work was executed by NEETRAC and the results are extraordinary. As soon as those results become public you can read about them here. In the mean time, actual post-injection performance of better than 99.6% on millions of feet of cable can be viewed at …

www.novinium.com/Lessons.aspx

Always skeptical of claims without data,

T. B. Frog

Euro-Rejuvenation

Dear Thermo,

I heard that besides the old rejuvenation technology offered by UTILX and Novinium’s improved technologies, that there is a third competitor in Europe.  Pray tell?

Hedging my bets

Dear Hedge-

There is only one firm in the world that can provide advanced Novinium technology. Today there are a total of twelve U.S. patents and their foreign equivalents. An up-to-date list of those patents is available at …

novinium.com/patents.aspx

If you want the safest and most reliable technology in the world, Novinium and our partners are the only source. Our friends down the road at UTILX Corporation offer technology invented by Novinium founders about two decades ago. Our founders are proud of their achievements, and this frog has written extensively that the performance of that old approach is quite good for non-demanding applications. Check with your risk management folks before you use that approach, however, because Novinium technology is much safer. Heaven forbid that you find yourself justifying your choice of a less safe choice to a jury. For a thorough discussion of the risks with all of the commercially significant injection approaches, check out my June 9^th, 2010 post, “Biggest Risk is Electrical.” Within that post is a link to a comprehensive risk analysis titled …

Rejuvenation Hazard Analysis 

There is a firm in Germany that offers silicone injection of power cables.  Their website is at …

www.kabelsanierung.de

Next, click on “Kabelsanierung,” which is German for cable rehabilitation. The firm is run by Professor Rudolf Wimmershoff formally at the Technical University of Regensburg. To this frog’s knowledge, Professor Wimmershoff’s rejuvenation approach has not been used too far from Bavaria. This frog cannot recommend the good Professor’s approach. He utilizes a common siloxane oligomer, which is generally used to waterproof masonry and such. The oligomer cross-links to a thick fluid resin after injection. The problem with this chemistry is that cross-linked polymers in the strand interstices can do nothing to improve the insulation’s dielectric properties, because they are way too big to diffuse into the insulation. To this frog’s knowledge there have never been any papers written to describe the post-injection performance of the good Professor’s approach. The firm’s primary businesses are transformer diagnostics and cable diagnostics.

Auf Widersehen,

Fehischlag Frog

Suitable for Treatment

Dear B.F.

We’ve taken some photographs of cable samples identified with off-line PD testing.  I was hoping to get your opinion of the cable and if injection would be able to address these issues.

·        On two samples, we found the XLP insulation was a greenish color.  We’ve never found cables discolored before and it had an odd odor.  Upon wafering and dying the sample, quite a few trees were found.

·        On three samples, we found spots where a hole was burned through the semi-con layer and dirt had gotten between the semi-con and insulation, causing some deep pitting.

I’ve attached some photos of the issues.  Neither of these cables has been treated, but can they? Let me know what you think.

Wishing you well,

Wisconsin

——————————————————————————————————————————————————————

Dear Wisconsin-

First off – green is a lovely color and you should be proud of your sample’s hue. The green color proves that the insulation compound manufacturer included anti-oxidants in its formulation and is generally an indication of recent heat exposure. The sulfur-based anti-oxidants break into by-products as they do their job. Some of these by-products absorb red light, leaving a predominantly yellow to green hue. The insulation may by 4201 made by Union Carbide, now Dow Wire & Cable. Click here to check out a fact sheet put out by the Dow folks called:

Color Indicates Presence of Antioxidants in XLPE Insulation Compounds

With regard to the odor, I can’t answer definitively for two reasons. One, you did not send me a sample and two, frogs are not known for their olfactory prowess. I can, however, speculate. The sulfur-containing anti-oxidant by-products are called thiols or mercaptans and have strong garlic-like odor. I have a cat at my house with an exceptionally keen nose. If you send me a stinky sample I can ask her to identify the chemistry involved. I hope it does not smell like tuna fish — she might gnaw on it. See "rats" below.

With regard to the water trees, you will find those in every solid dielectric cable. Water trees are the predominant cause of solid dielectric cable failure. Fortunately, Novinium provides fluids that can reverse the damage caused by water trees and replace the anti-oxidants that have been consumed over decades of field aging.

·        Click here to learn how you can know that water trees are the predominant cause of cable failures.

·        Click here to learn how you can be confident that rejuvenation will reverse the damage caused by water trees.

·        Click here to learn how Novinium^®-brand Ultrinium™ fluid can replenish the anti-oxidants in aged cable.

Deep Pitting

I don’t know if the cable with the holes in it smelled like garlic, but the rodents that chewed on it must have liked the odor.  I doubt that the meal was satisfying. I am fond of rodents. An adult mouse fills my belly for the better part of a week, but I might have taken a pass on the gal that was chewing on your cable. Shreds of polyethylene in her belly would end up in mine and would undoubtedly upset my delicate digestion. I suspect the rat stopped chewing when she started to feel a tingling in her mouth – those were partial discharges. Persistence would have led to an untimely end. That’s how I know the rat was a female. A male rat would not have been smart enough to back off when he felt the tingles … in fact they probably would have only encouraged him more.

Here is a question for you, Wisconsin. How many cables had to be examined to find these rodent bites? If rodent damage is rampant in your service territory, off-line partial discharge testing might be a useful tool to find where the rats reside. It is true, that rejuvenation cannot address rodent damage, but how prevalent is this failure mode? For some insight on that question check out my three-part postings of January 2012 …

Failure Causes I, Failure Causes II, and Failure Causes III.

The Novinium masters of reliability have been involved in the injection of many millions of cable feet. Cables with water trees, with or without interesting color and odor, are handled easily and these represent the frog’s share of the root causes of cable failure. Add in component issues addressed by rejuvenation and a tiny minority of potential issues are left unaddressed. It is for this reason that more than 99.4% of all cable treated by Novinium enjoy failure-free reliability.

Never put anything in your mouth that can kill you,

T. B. F.

Real World IV – NE Utilities – finally a ray of sunshine

In my last post of 2011, Wondering in Western Washington, questioned the merit of the claims made by UTILX^® in a document titled, “Life Extension Estimate for UtilX^® CableCURE^® Rejuvenation Fluid.”  That document includes 17 pages and numerous claims. In this fourth in a series of five posts, I consider two paragraphs on page 15 devoted to some “real, real world” data provided publically by Northeast Utilities, Connecticut Light & Power subsidiary.  The author devoted the previous 14 pages to the “Duke Deception” and the “Dominion Dodge,” each a poster child for the Wikipedia entry for “Non-representative Sample.” We saw that those two examples were displaced from the “real, real world” by 20X to 240X! So here is what the author said with his characteristic flair about his third and final example:

Part Three:  Connecticut Light and Power Co. Published Success:

Part One of this paper demonstrated that the fluid content contained in a cables' insulation even many years post injection is very high. Part Two of this paper demonstrated the long term effectiveness of that fluid on real cables that underwent real world ageing. Part Three of this paper shows a published real world accounting of the effectiveness of treatment on a real world population of cables. This accounting was performed by Connecticut Light and Power Co (CL&P). It was presented in the spring 2008 ICC and published in those notes. The spreadsheet describing their injection program success has been included as Appendix C of this report. That spreadsheet makes the following points.

CL&P has been carefully maintaining the failure records of the cable they consider to be 'at risk' since 1995. They began their injection program in 1999 selecting cable from that same pool of 'at risk' cables. Although the appendix includes a detailed breakout by year, the summary is succinct. From 1999 to 2007 the pool of at risk un-injected cable totaled 7.8 million feet upon which they experienced 2512 failures. From that same pool of at risk cables, 2.1 million feet had been pulled for injection. Across that same time period there are only 43 failures experienced on the 2.1 million feet. The un-injected pool is suffering a failure rate per foot of cable that is larger than 15 times greater than the cables that have been injected.

The first two sentences are of course untrue. Part One and Part Two demonstrate that under conditions unrepresentative of typical cables and in the least demanding of applications, PMDMS (phenylmethyldimethoxysilane) fluid works quite well. What this frog struggles to fathom is why the author didn’t just stick to CL&P data. The CL&P data show the profoundly positive impact that PMDMS fluid has on, dare I say it, real world reliability. The post injection failure rate is 0.7% and it is does represent an over 15-fold improvement over the untreated cable population. In the interest of transparency, I have attached the CL&P data to the bottom of this post.

Conspicuous by its Absence

What’s missing from the “Life Extension Estimate for UtilX^® CableCURE^® Rejuvenation Fluid” document is any analysis that shows the “real world” concentration of treatment fluid in the CL&P cables. This would be the proper way to draw together the Duke, Dominion, and CL&P data. At Novinium, we don’t have to make measurements to know what the concentration profile looks like. We have two U.S. Patents (7,643,977 and 7,848,912), which allows us to calculate the profile with uncanny precision. If the author were to make a measurement, it would not support his narrative. The author would find that the concentration of fluid found in the Duke transmission cable and the unloaded 35kV Dominion feeder cable are substantially greater than that found in a similarly aged 7-strand or 19-strand CL&P URD cable. I should think the author would want to revise his thinking.

In any case, there is good news. For non-demanding applications in cool mesic soils such as those in Connecticut, even the first generation of fluids performs admirably. Novinium offers the same PMDMS-based treatment fluid with several safety and performance improvements. We call our PMDMS-based material, Perficio™ 011 fluid. Numerous improvements in the next generation of technology made by the Novinium Masters of Reliability™ provide up to twice the life and twice the post injection reliability with the Ultrinium™ 73X fluid family. What do the “real world” folks in Connecticut use today for their rejuvenation program? To find out you will have to ask them, but I can say that I have added granite to my habitat.

In my upcoming fifth and last post on this thread …

Real World V – Irrefutable Proof, …

I will provide a final peer review and editorial of UTILX’s “Confidential and Proprietary” document.

Until then,

T. B. Frog

80-20120127_Real_World_IV-NE_CLP_Cable_Injection_Program.pdf (8.14 kb)

 Crow

Dear Frog of Knowledge,

Can you explain the Crow-AMSAA graph on Novinium’s web site at novinium.com/lessons.aspx?  How do I compare Novinium’s post-injection reliability to that of UTILX?

Not wanting to eat crow,

‘raven Reliability

 Dear ‘raven-

What a great play on words! My fans that compose creative questions get to move right to the front of the queue.  You are justified in “c’raving” reliability. I took the opportunity your inquiry provided to update the Novinium failure statistics through August 10, 2011. I present those statistics in the chart nearby. Crow was a guy that worked for the “Army Material Systems Analysis Activity” or AMSAA.  Crow developed the statistical model that now bears his name and that of his employer.  Crow-AMSAA or “C-A” for short is widely recognized as a preferred model to predict the reliability of complex systems that experience multiple failure mechanisms.

The x-axis is the product of the feet of cable that have been treated by Novinium and the years that have elapsed since treatment.  For example, if a 328 foot (100 meter) length of cable was treated three year ago, its contribution to the cumulative treated would be 984 feet*years.  The x-axis is logarithmic.  Plotted against the y-axis are the failures – 56 in total.  A least squares regression of the failures provides a slope, or beta, of 0.64.  A beta less than 1 means the failure rate is decreasing.  Process and chemistry improvements, together with the improving mastery of the Novinium’s craft workers, make Novinium technology more and more reliable.  That’s not to say that when Novinium began injection operations over six years ago post-injection performance was unacceptable.  Novinium started where the old technology, invented by Novinium founders, reached a reliability plateau. When I did this same C-A analysis nine months ago (November 2010) the beta was 0.72.  So, not only is the failure rate decreasing, but the rate of decrease is accelerating!  About 99.4% of all the cables, which Novinium have treated, remain in reliable service.  This is at least twice as good as the other guys!

With regard to how you can compare Novinium reliability with that of UtilX, I can only provide you with some frog-advice. As a circuit owner you should demand that UtilX publish its total failure statistics – not just a few select circuit owners, the whole data set.  Then circuit owners would be able to make an apples-to-apples comparison. Don’t hold your breath, when NEETRAC, their sponsoring circuit owners, and other industry leaders invited UtilX to participate in a side-by-side laboratory experiment, UtilX helped craft an experiment, but withdrew their participation when the experiment actually began.  By the way, that experiment is complete and included the only rejuvenation firm willing to share their post-injection results in a truly independent experiment – that would be Novinium. UtilX demurred, citing “business and commercial reasons.”

No need to crow when you can croak,

T. B. Frog

Dearest Green One,

I have a need to rehabilitate some aging URD circuits.  How long have Novinium fluids and injection technologies been in use?  I prefer to use proven technology.

Signed,

Middle East Query – Novinium References

Dweller of the Desert asked 22 questions in his post …

Middle East Query – 22 Questions.

In this installment I address question 7.

7.   Does Novinium have proof of success available (references)?

The institution of Novinium has worked for over 75 different utilities and industrial customers around the world.  That’s pretty impressive, but institutions don’t have experience – the people within those institutions have experience.  The masters of technology and the master craftsmen, who are the people of Novinium, have experience at hundreds of utilities and industrial sites on every continent except Antarctica.  When we work in January in northern Alberta Canada, it just looks like Antarctica!  Ask your sales professional for a sampling of where the Novinium team has worked.  Also check out dozens of case studies at www.novinium.com/CaseStudies.aspx.  Here is something else you don’t usually see, we share our lessons learned too!  Check those out at http://www.novinium.com/Lessons.aspx.  Want more?  We publish our overall failure statistics.  I provide those results nearby in a Crow-AMSAA graph.  The Crow-AMSAA plot shows an overall failure statistic for our collection of technologies.  The slope (β) of the line is less than 1, which indicates a declining rate of failure – a benefit of continuous improvement.  The overall success rate of about 99.1% is as good as it gets.

How about truly independent testing?  Novinium is the only rejuvenation supplier in the world that would participate in a NEETRAC side-by-side rejuvenation test.  The other guys declined to participate citing “business and commercial reasons.”  I am not entirely sure what that means, but one possible translation using frog-logic:  “We don’t want a direct performance comparison of 20-year-old technology against Novinium’s state-of-the-art patented technology.”  What do you think?

For now, Ma’a salama (مع السلامة/Good bye)

T. B. Frog