by Thermo 2. April 2012 19:19

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

by Thermo 7. February 2012 14:55

HFDB-4201 From Dow Wire & Cable, “Color Indicates Presence of Antioxidants in XLPE Insulation Compounds”; Lovely vented and bow-tie trees are in every solid dielectric cable. Rejuvenation specifically addresses these. 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.

by Thermo 12. September 2011 20:53
 Concordance of IEEE 400.2™ & Warranty

 

Dear Astute Amphibian,

 

The definition of “Discouraged Diagnostic Testing” found in your warranty language does not seem to allow VLF testing in accordance with IEEE 400.2.* In the unlikely event that a rejuvenated cable fails in service, we would want to repair the fault and test the cable with one of the approaches outlined in IEEE 400.2. Is there some reason we should not, or cannot, test using IEEE 400.2 protocols?

 

Signed,

Power Creek

Dear Creek-
 
Inscribed in stone on the Novinium warranty are the following words:
 
Discouraged Cable Diagnostic Testing includes any exposure of the cable Segment to (1) a voltage greater than 50 volts at any frequency below 50 Hz or above 60 Hz, (2) any exposure of the cable Segment to voltages at any frequency above the rated voltage of the cable, (3) any cable testing with duration greater than 2 minutes, or (4) any DC cable testing at a voltage greater than 1 kV.
 
Each word was chosen very carefully and the keyword to address your question is the first.  The first word is “Discouraged,” not “Prohibited.”  IEEE 400.2* points out in several places, such as the bottom of page 5, that …
 
“… when the cable system insulation is in an advanced condition of degradation, the diagnostic tests can cause breakdown before the test can be terminated.”
 
Most cables that are rejuvenated are in an “advanced condition of degradation.”  In fact, most solid dielectric cable of vintages manufactured prior to 1985 is in an “advanced condition of degradation.”  The diagnostic tests described by IEEE 400.2 may cause a cable to fail that otherwise would have provided reliable service. Novinium’s masters of reliability discourage activity that may exacerbate incipient reliability issues, but we do not presume to prohibit.  In the case, where such testing is performed on rejuvenated and reliable cable the warranty is suspended for 120 days, not forever invalidated.
 
Furthermore, in your particular scenario the warranty situation is moot.  When a Novinium rehabilitated cable fails, Novinium’s standard warranty provides money-back to the circuit owner.  After Novinium disburses the refund, there is no further warranty obligation on that section of cable. The circuit owner is unencumbered from using any of a plethora of available destructive diagnostics.
 
Astutely yours,
 
Thermo
 
*IEEE 400.2™ is the IEEE Guide for Field Testing of Shielded Power Cable Systems Using Very Low Frequency (VLF). IEEE 400.2 is a trademark of the IEEE.

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Warranty Reflections

by Thermo 1. September 2011 17:28

DC Testing

I don’t reflexively follow the crowd, but the consensus is that DC testing is destructive and does not provide useful data anyway!Dear Ms. Frog,

We have been using DC testing for centuries without any problems. How do you explain that, oh wet and wise one?

Oregon Anomaly

Dear Anomaly-

DC testing of medium voltage AC cables comes up only occasionally.  I discussed the warranty impact in an April 14, 2010 post, titled “DC Testing to sectionalize faults – Warranty Impact.”  Click here to check out that post. There are many anomalies in Oregon that may never be explained, but it seems unlikely that the laws of physics are different in The Beaver State. I suppose there is a chance that everybody else is wrong and you are right. It happens to me all the time that I defend a position that is contrary to conventional wisdom.

I am actually not an expert on DC testing, so I have to rely on those that are.  One way I can be pretty sure that DC testing is inherently destructive is that the folks that manufacture and sell DC testing equipment croak along on the same chorus.  To wit, HV Diagnostics, Inc., one of the most respected suppliers of high voltage test equipment pronounces in its brochure:

“On Medium Voltage Extruded (XLPE, PE, EPR) cables, DC is no longer recommended by most international standards. DC has been found to be both destructive, causing premature failure of aged MV cables, and/or ineffective in detecting many types of serious pending insulation defects in new and old cable installations.”

You have to take that kind of pronouncement pretty seriously, because the supplier sells DC testing equipment.  As for your anomalous experience, I would recommend that you compile a comprehensive data set and use randomization and suitable controls.  Anecdotal results are inherently misleading. Also make sure that the equipment operator’s job does not depend upon the results – the guys that do testing for a living seem generally to be proponents of testing.

In cahoots with the beavers,

T. B. Frog

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Potpourri

by Thermo 25. August 2011 20:47

Tanδ ex post facto

Dearest Amphibian,

I have sent you some before-and-after diagnostic data (0.1Hz tan-delta) on two cables treated with Novinium® Ultrinium™ 732 fluid? The results are extraordinarily positive. What say you?

Greater Chicago

Dear Greater-

The data you provided is reproduced in the chart nearby. A few of my historical postings provide evidence that I am not a big fan of diagnostics. For example check out the postings below ...

2010-11-12 Diagnostic Testing – Should I do it?

2010-12-12 Electrical Treeing and the Principle of Parsimony

2011-05-11 Middle East Query – Diagnostic Testing Timing

2011-05-19 On-line Diagnostic Testing

Check out the before-and-after dielectric spectroscopy data presented in another post when I addressed tan delta measurements specifically at …

2010-09-10 Cable Rejuvenation Impact on Loss Factor (tan-Delta)

The data from the University of Connecticut’s Electrical Insulation Research Center (EIRC) in that post leaves no doubt that rejuvenation has an impact on tan delta measurements, but it creates considerable doubt as to the meaning of that impact. It is also true that there can be no doubt that rejuvenation with Novinium fluid technology provides a reliable post-injection life extension – over 99.6% of all treated cables are providing failure-free performance.

It is tempting, whether human or amphibian, to embrace data when it reinforces what you already know. As a disciplined scientist, I, however, am able to resist that temptation. The 17 month improvement demonstrated by the Illinois Cable 1 and Cable 2 data suffers at least two shortcomings. First, there were precisely two cables measured two times about 17 months apart. That is not a statistically significant data set. Second, without following the tan-delta over time, it is not possible to correlate the “improvement” with a reliability-metric like AC breakdown performance, which has been measured and modeled extensively. We can rectify these two issues with a more comprehensive analysis that includes more cables and more frequent periodic re-testing. Such a program is in the works with Greater and we will report on the results as the data becomes available. The testing itself carries risks for the cables to be tested. Knowledge is not free and you can’t make an omelet without breaking some eggs.

Interested, but skeptical,

T. B. Frog

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Potpourri

by Thermo 1. June 2011 16:26

Integrated Diagnostics 

Dear BF,

My firm will consider and evaluate additional services beyond rejuvenation that will add quality or value to a requested proposal.  Additional options for cable testing services would be of particular interest.  An explanation of services and associated costs must be included with all additional service offerings.  Information submitted for this may lead to additional evaluation points in the “services to be provided” category.

Please help me with my decision matrix,

Tahoma

 

Dear Tahoma-

For my readers who are not local to the Pacific Northwest, like you and I, Tahoma is a local Indian name, which means “snow peak” and designates Mt. Rainier, the snow covered volcano close to Seattle and Tacoma.  I have a view of Tahoma from my pond too – feel free to visit me anytime and I will be happy to share my grubs.  I’m all for decision matrices.  Every time one of these has been used Novinium comes out on top – safer, faster, better.

Your query suggests that you have a particular interest in cable testing services.  I have provided several posts in the past that describe the issues and challenges associated with diagnostic testing.  I list several of them below for your review:

In short, this frog is skeptical of claims of efficacy for any of the commercially available diagnostic tests.  Compare the double-digit false positives and double-digit false negatives inherent in testing with this single digit – one percent.  That’s the number of post treatment failures that have occurred in all cables proactively treated with any of the globally commercialized rejuvenation technologies.  Novinium’s post-treatment reliability record is even better than the average!

Occasionally there are cases where diagnostics are appropriate.

Novinium’s diagnostic tool box includes several kinds of instruments including infrared imaging and three kinds of on-line partial discharge detectors.  Novinium uses infrared imaging technology to identify improperly installed compression connectors.  The picture nearby shows a side-by-side image of two splices, one installed properly and the other suffering from thermal runaway.  Three different on-line partial discharge detectors are available to pinpoint discharges in terminations, splices and cables.  A high frequency current transformer can be clipped around a cable or its neutrals to detect discharges in the cable or connected equipment.  A Transient Earth Voltage (TEV) sensor allows the pinpointing of local discharges.  For applications where it is not prudent to approach a piece of operating equipment such as air operated switchgear, an airborne acoustic sensor can locate discharges inaudible to the human ear.

In addition to these instruments, Novinium provides consulting services to circuit owners to diagnose problem areas using failure data.  This approach is the lowest cost and most accurate diagnostic available.  The method was documented in a DEIS (Dielectrics and Electrical Insulation Society) Feature Article in the March/April 2009 issue of IEEE Electrical Insulation Magazine, Diagnostic Testing of Stochastic Cables.

Diagnostically yours,

Thermo B.F.

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Potpourri

by Thermo 19. May 2011 14:14

 On-line Diagnostic Testing

Dear Ms. Conducting-

Thank you for your comment of May 13, 2011 to Middle East Query – Diagnostic Testing Timing.  Click here to see the original post and comment.  In short, Ms. Conducting wanted to dive deeper into the data. Below I have reproduced slide number 281 from the CDFI (Cable Diagnostic Focused Initiative) Regional meeting presented by NEETRAC (The National Electric Energy Testing Research & Application Center at Georgia Tech’s College of Engineering) and hosted by American Electric Power (AEP).  The meeting was held on October 13-14, 2009 in Columbus, Ohio, U.S.A. The entirety of the presentation slides are available by clicking here. The figure below (from slide 278) shows the failure results tracked for over three years on 114 feeder cable miles tested using online PD on cables that included EPR, XLPE, and PILC cables. After the testing was completed, the cables and attached accessories were allowed to fail – that is, no rehabilitation actions were taken.  There were about 85 accessory failures; there were about 90 cable failures.

Definitions

False Positive – Testing indicates the existence of an incipient fault in a cable or accessory, but the presumed incipient fault does not progress to a fault during the observation period.

False Negative – Testing fails to indicate the existence of an incipient fault in a cable or accessory, and the unidentified incipient fault progresses to a fault during the observation period.

 

 The online PD testing indicated the need for action (i.e. imminent failure) on 45 accessories.  Of the identified 45, 14, or 31%, actually failed.  The false positives were 69%. The results on the cable were marginally better. Of the 52 cables, which were diagnosed as “bad,” 23 actually failed or about 44%.  The false positives were 56%.  For both accessories and cables the number of faults that occurred on plant, that had been deemed “good” by the testing firm, far outnumbered those identified as “bad.”  There were about 71 and 67 false negative failures for accessories and cable respectively.

Not only did the observations show that the testing was unable to provide reasonable discrimination between bad and good, the raw number of failures that occurred in the presumably “good” sub-population was about 3 to 5 times higher. Because the researchers did not provide population statistics beyond the total mileage of cable installed, it is not possible to determine with precision the relative false negative performance. However, I can make some frogstimates. If the average three-phase feeder run length were 1760 feet (typical for North America) and there were 2.2 components per cable segment (also typical), there would have been approximately 343 cable segments (or about 114 three-phase cables, termination to termination) and about 750 accessories.  The relative failure rate over the three-year period would have been 11% (i.e. 85/750) for accessories and 26% (i.e. 90/343) for cables. My frogstimate of the false negatives are 9.5% (i.e. (85-14)/750) and 19.5% (i.e. (90-23)/343) for accessories and cables respectively.

Amazingly, these profoundly dismal results are spun by testing proponents as proof that a testing program is a fruitful endeavor. It’s no wonder to me why humans get sucked into tulip and real-estate bubbles and Ponzi schemes – no frog has ever been so duped.  There have been a few would-be-princesses that have been duped by a frog, but never the other way around.  Alas, wishing that a frog is a prince does not make him so. Wishing that a diagnostic provides useful information does not make it so.

There are two immutable reasons and their “anti-synergy” that explain why the current generation of diagnostics cannot work. These two reasons are:

1.   The economics of aged circuit rehabilitation, and

2.   The second law of thermodynamics.

Further, without some technological breakthrough that reduces the cost of applying diagnostics by an order of magnitude, it is unlikely these immutable and anti-synergetic forces will ever be reconciled. To inoculate yourself from these ill-conceived schemes, read and understand the DEIS (Dielectric and Electrical Insulation Society) feature article, “Diagnostic Testing of Stochastic Cables” published in the March/April 2009 pages of IEEE’s Electrical Insulation Magazine.  Click here to learn.

Data and Frogs don’t lie (unless you’re a fly),

T. B. Frog

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Potpourri

by Thermo 11. May 2011 19:44

Middle East Query – Diagnostic Testing Timing

Dweller of the Desert asked 22 questions in his post …

Middle East Query – 22 Questions.

In this installment I address question 13.

13.   Can the customer test the cable right after injection? Could it be done immediately? If not, after how many days, weeks or months?

You are not going to like my answer, but this frog is incapable of subterfuge. There are no cable testing methods that will tell you when a cable will fail, which is what you really want to know. At best, testing will provide you a number you can track over time. An extensive U.S.A. study, the Cable Diagnostic Focused Initiative (CDFI) led by NEETRAC (The National Electric Energy Testing Research & Application Center at Georgia Tech’s College of Engineering) of commercialized cable testing methods came to this conclusion—see CDFI slide 41. The CDFI is the largest and most comprehensive study ever undertaken. All cable testing methods, except online PD testing, can cause damage to the cable insulation and shorten cable life.  Some cable testing methods such as Tan Delta or Power Factor are not comparable before and after injection, because cable injection alters the chemistry and physics of the cable, changing the measured parameters in ways counter to the claims of the diagnostic supplier.  See my 2010, September 10, post, “Cable Rejuvenation Impact on Loss Factor (tan-Delta).” In one example from that post, the tan-Delta at 0.1Hz increased after treatment, even though dielectric strength increased substantially – just the opposite of what the proprietors of the test predict. Because available diagnostics do not provide useful information and/or the tests are inherently destructive, Novinium discourages cable testing before or after cable injection. If a circuit owner chooses to test its cable despite overwhelming evidence of futility and counter productivity, before or after injection, Novinium will suspend, but not extend, any warranty for 120 after the test. Make sure you check out my 2010, November 12 post: Diagnostic Testing – Should I do it? One sneaky way to test the veracity of diagnostic firms’ claims is to request a warranty for cables which test as good, but fail. And when I say warranty, I don’t mean a credit for future diagnostics – I mean money back.  In a three-year experiment undertaken as part of the CDFI to measure the accuracy of online partial discharge testing, false negatives were about 9.5% and 19.5% for accessories and cable respectively.  False positives were 69% and 56% respectively.  I can do better than that with a role of the dice!

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

T. B. Frog

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Operational Considerations | Potpourri | Warranty Reflections

by Thermo 21. April 2011 16:01
Middle East Query – 22 Questions
Dearest wet one,
 
Frogs are few and far between,
The Arabian Peninsula is where I am at,
Allow me to set the scene,
Sand spread on the flat.
 
Even though our climate is dry,
And oil production is what I do,
It’s true our cables often fry,
May I inquire twenty-two?
 
Inquiry
Answer
1.     What kinds, types, and sizes of power cables can be injected?
2.     What kinds, types, and sizes of power cables cannot be injected?
3.     How old is cable injection technology?
4.     How much time does it take to inject a certain length of cable?  What is the maximum cable length that can be injected?
5.     How much time does it take to locate splices? Who will identify the splices? Is it the contractor or the customer?
6.     Does the injection apply only at utilities or at industrial plants too?
7.     Does Novinium have proof of success available (references)?
8.     How do you rejoin cable ends after an old splice is removed?
9.     Will the injection affect the semicon around the conductor since the fluid will penetrate through it?
10.   Can injection be carried out twice on the same cable after 10-20 years of the first injection?
11.   How many years will the curing extend the life of the cable?
12.   What is the expected cost of curing compared to cable replacement?
13.   Can the customer test the cable right after injection? Could it be done immediately? If not, after how many days, weeks or months?
14.   Does Novinium have any available research papers or studies?  Does Novinium have IEEE articles?
15.   Does Novinium have any type/kind of certification?
16.   What if my cable strands have water block design elements?
17.   Does injection have any impact on cable ampacity?
18.   If a cable were to fail after injection, can the customer use ordinary splices? Or should he use the “Novinium” specified splice? Can we use the traditional splices and terminations if a fault took place after treatment? In other words, do we have to use your splices and terminations on any treated cable all the time or that is only during treatments?
19.   Do the existing cable terminations need to be replaced? Will this introduce new splices?
20.   Are your splices and terminations available in the market or it is unique to Novinium?
21.   If we have to use your splices and termination all the time, do we need special training for our technicians and if yeas can provide such training and how much is cost?
22.   Did you type test your splices and terminations and are they certified to be used in such applications?
 
Hal beemkanek mosa’adati? [Editor:  هل بإمكانك مساعدتي؟/Can you help me?]
Dweller of the Desert
 
Salam Dweller of the Desert-
 
I have visited your beautiful country.  I snapped the photo nearby of your lovely red sand dunes as I drove from Riyhad to Al Khobar.  Mind you, I do not wander through the desert, as the dry sand irritates my lovely and moist skin.  Twenty-two questions is too many to deal with in a single post, so I will batch the questions and answers into a series of posts.  Links will appear in the table nearby as those posts become available.
 
For now, Ma’a salama (مع السلامة/Good bye)
T. B. Frog
by Thermo 18. March 2011 13:54

Really Long Term Life

In my December 29, 2010 post at …

Crazy-Competitor-Claims

Wonderer in the Wilderness inquired …

1. How can Novinium get the same cable life extension without a soak period?  It would seem to me that Novinium puts less fluid into the cable than one would get with a soak period.

In my first post addressing this question I provided an abbreviated answer. We learned from the abbreviated answer that that when Novinium founders conceived of the first generation of treatment fluid over two decades ago, there was a failure to check the relative diffusion rates of the phenylmethyldimethoxysilane (PMDMS) monomer and the condensation catalyst we had chosen to provide long life.  This turned out to be a grave mistake, which we have corrected.  In a subsequent post on January 3, 2011 at …

Catalytic Considerations – Component I

… I provided a more comprehensive answer, but I promised five new posts that would explain the functional improvement of the five kinds of ingredients in Ultrinium™ 732 and Ultrinium™ 733 fluids.  In this last of those five sub-posts, I explain how a component with a really ugly name provides extraordinarily long life.  Chemists call the material found in Ultrinium™ fluids cyanobutylmethyldimethoxysilane (Pronounced: Sigh-an-Oh•butte-ill•meth-ill•die-meth-ox-ee•sigh-lane); we will call it CBMDMS for short.

In the graph nearby I explain the first dimension of why CBMDMS works so well for so long.  The graph plots the “permeation product” of the three most commercially important rejuvenation silanes.  Permeation is the product of the diffusion coefficient and the solubility of the material in cross-linked polyethylene (XLPE).  The rate of fluid exudation from a cable is directly proportional to this permeation product.  Remember that if a fluid exudes out of the cable, it is not providing any life extension benefit.  The lower the permeation value, the longer the fluid will stay in the cable.  The permeation of the primary ingredient in Novinium’s Perficio™ 011 fluid and other older technology fluids is illustrated by the light-blue-colored (upper-most) line over the range of 15 to 90°C.  This fluid is called phenylmethyldimethoxysilane (Pronounced: Fen-ill•meth-ill•die-meth-ox-ee•sigh-lane) by chemists; we will call it PMDMS.  In a recent post, Chain Entanglement, I explained how extending the length of the side chains entangled the silicone in the polyethylene polymer chains and slowed the diffusion.  The orange line shows the advantage enjoyed by tolylethylmethyldimethoxysilane (Pronounced: Tall-ill•eth-ill•die-meth-ox-ee•sigh-lane by chemists) or TEMDMS, which is a result of this chain entanglement.  The permeation rate and proportional exudation rate of TEMDMS, is always lower than that of PMDMS.  At low temperature they are about the same, but at 75°C, the TEMDMS permeates about 5-times slower.  But the focus of this post is the amazing CBMDMS, which enjoys a 25-fold to 45-fold permeation advantage over the PMDMS.  That’s a really big deal!  At 75°C CBMDMS will outlast PMDMS by a factor of 45!

TEMDMS and CBMDMS are available only from Novinium, as their use is protected by U.S. Patent 7,643,977, other pending applications, and their foreign equivalents.

 

3D rendering of CBMDMS or cyanobutylmethyl-dimethoxysilane (and proper pronunciation)

 

The second really cool thing about CBMDMS, besides its incredibly long persistence in the cable, is how it works.  If you look carefully at the CBMDMS molecule just below its permeation line in the graph or in the video, you may notice the feature from which it gets its name.  A carbon-nitrogen triple bond and an unbonded pair of electrons make a cyano-group.  This cyano-group (alternatively called a nitrile-group) is very polar, that is, it has a positive end and a negative end.  Consequently, CBMDMS has a very high dielectric constant.  Its dielectric constant is between 50 and 100, which puts it on par with the dielectric constant of pure water.  Ultrapure water is used in high voltage electrical laboratories’ water terminations to grade electrical stress.

 

The cyano-group, found only in Novinium rejuvenation products, grades stress in the same way, but at the nano-scale.    Before I explain how this works we need to define a thermonuclear-sized word:  dielectrophoresis, pronounced die-EE-lek-trow-for-EE-sis or DEP for short.  DEP is a phenomenon in which a force is exerted on a dielectric molecule when it is subjected to a non-uniform electric field – the greater the dielectric constant of the material, the greater the force.  The illustration nearby explains how the diverging electrical field near an imperfection imparts a force upon CBMDMS molecules and draws them into the local-region of highest electrical stress.  The presence of the high dielectric constant material smoothes the electrical stress and interferes in several ways with dielectric failure mechanisms:

1.    The local AC stress is reduced, and water trees grow more slowly.

2.    The high electrical fields around space charges are reduced, which reduces the likelihood of UV photon creation and the inception of free electrons.

3.    Any free electrons will not be accelerated to the same energy as they would have been in a greater field.

4.    The reduced local field increases both the partial discharge inception and extinction voltages.

Greater persistence in the insulation and stress grading provide longer post-injection life even in demanding applications.  Performance at high temperature and performance in cables with constrained geometry that limit the amount of fluid that can be supplied, are greatly enhanced by the presence of CBMDMS.

Longer life through better chemistry,

Thermonuclear B.F.

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