I couldn't find any instructions for tape terminations of cable in the 8th edition of the Lineman's and Cableman's Handbook. You might want to confirm that the 11th edition has what you need before purchasing.
I'd try contacting 3M. They probably have instructions available.
Contact 3M via phone or a local rep. Their website is terrible.
Also try contacting good electrical contractors in your area who do medium voltage cable splicing and terminaitons, I am sure their HV electrician carries the instructions.
Maybe I'm living in a different world, but the last time I saw a built-up tape stress cone was about twenty years ago. The kits take a lot of the specialized knowledge and trouble out of the picture, not to mention the man-hours of labor.
I know. I've built them from scratch myself, and I've used the kits. It is a long, time-consuming job to do one by hand. Using the kit is much faster. I don't see any high rate of failures form the kits if they are properly applied.
Of course, you need a wide selection of kits for different cable types, sizes, voltages, etc., where one big cabinet full of tape will work for everything...
I have an old GE cable catalogue that has details for building stress cones. GE is not in the cable business any more.
Someone in Okonite probably has details for making stress cones. Call them up, it may give them a laugh.
Oldfieldguy is right. We use to allow 8-12 hours per stress con, now it's 1-1/2 to 2 hrs max per termination.
Oldfieldguy:
Sometimes we still use the old tape kits to terminate cable ends or to join cables. But I have to agree with you, I do not think there are a lot of guys who still can do a tape termination/joint, and yes, it takes some time.
Regards
Ralph
[red]Failure seldom stops us, it is the fear for failure that stops us - Jack Lemmon[/red]
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I have a book but unfortunately I don't think you can buy it. It is a special publishing by the NJATC.
I can hand tape. I keep the skills up even though I don't do it often. Some places still demand hand tapped splices and terminations. When done right they will out last the kits. A high voltage contractor in my area will guarantee kits as long as the manufacture guarantees the kit. They with guarantee their hand taped splices and terminations for the life of the cable.
They find a lot of bad kits when performing partial discharge testing. Mostly due to workmanship issues. So they do a lot of work cutting of kits and installing hand tapped terms in their place.
If you buy the 3M tape kits they come with directions for standard and "shorty" terminations. The 3M method is similar to a capacitive stress relief system as apposed to a geometric "stress cone." The "shorty termination is great where you are in a really tight place. You can make a 15KV termination that is only about 10" long as apposed to the standard 3M taped term that is about 23" long.
I've found quite a few bad installations of stress cone kits. The problems generally fall into two categories: poor cable prep: not removing all the semiconductive layer and its residue from the cable, and second, failure to keep surfaces clean and dry before installing the kits.
In my field experience, we didn't do partial discharge testing. We applied a very specific regiment of DC hipot testing, and we found stress cone "issues" that would have "passed" a go/no-go hipot test using a less rigorous application.
And, yes, I do know of hand-laid stress cones that have been in service almost fifty years... I also know of some that didn't make the week... They depend to a very large extent to the expertise and attention of the electrican making the application. The kits remove a large chunk of the expertise, but not all of it, and they still require care in installation.
But, hey, if it was easy, we'd let anybody do it...
