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#25690 - 05/16/03 11:22 AM Taping up joints
Bill39 Offline
Registered: 11/28/01
Posts: 75
Loc: Indianapolis, IN, USA
OK, for a conversation starter what is your preferred method of taping up larger transformer and motor lead connections? As an apprentice, it seemed like every journeyman I worked with had a slightly different idea. Some used rubber, then plastic tape. Some used an initial layer of plastic tape, then rubber, then a final layer of plastic (the initial layer of plastic was put on sticky side up and was to prevent the rubber tape from adhering to the lugs). Others used varnished cambric, then plastic tape. Others used friction tape somewhere in the mix also.
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#25691 - 05/16/03 12:25 PM Re: Taping up joints
sparky Offline
Registered: 10/18/00
Posts: 5303
methods vary per enviroment

my 'bombproof' method....

scotch gaurd
dux seal (thin layer)
splicing tape
regular tape
marking tape

bake @ 480V for 45 min
serve hot
#25692 - 05/16/03 01:11 PM Re: Taping up joints
Redsy Offline
Registered: 03/28/01
Posts: 2056
Loc: Bucks County PA
There are many newer types of mechanical or compression connectors with snap on covers or rubber boots available that split-bolts may be on the road to becoming obsolete.
Time-wise there is no comparison.
#25693 - 05/16/03 04:41 PM Re: Taping up joints
sparky66wv Offline
Registered: 11/17/00
Posts: 2232
Loc: West Virginia
Varnished Cambrick for mechanical Strength (keeps the sharp parts from poking through) 50% overlap, two layers, one up, one down...

Scotch 130C sticky side out, 50% overlap, two layers, one up, one down stretching tight to prevent voids...

Scotch 33 50% overlap, two layers, one up, one down...
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#25694 - 05/16/03 04:49 PM Re: Taping up joints
golf junkie Offline
Registered: 04/22/01
Posts: 507
Loc: York, NE
Friction, rubber, plastic works fine, lasts a long time!

I avoid spit bolts whenever possible. I'll use lugs when I can.

#25695 - 05/16/03 05:32 PM Re: Taping up joints
elektrikguy Offline
Registered: 05/25/02
Posts: 132
Loc: woodstock,ga,usa
I agree with "Junkie". Have never had a call back when using this method. Always make sure to wrap tape in direction corresponding with the tightening of a wire nut if used. I would never have thought to have to watch this but have a had a couple apprentices wrap backwards. Of course it was fixed before cover and terminations were completed. Go figure I get a couple of apprentices with those "left handed" tools.
#25696 - 05/16/03 05:38 PM Re: Taping up joints
Bjarney Offline
Registered: 04/10/02
Posts: 2527
Loc: West-Southern Inner-Northeast ...
Bolted compression lugs (with a star lockwasher or kep nut) cover 18AWG to 500kcmil. A cambric inner layer allows for splitting open like a clamshell on rework.
#25697 - 05/18/03 03:10 PM Re: Taping up joints
mlk682 Offline
Registered: 04/14/03
Posts: 48
Loc: Foley Mn

I use two half laps of moxness and a layer of 88 (scotch)on 480 and below. On higher voltage terminations I use more half laps based on the mil thickness of the tape i had that day. Otherwise I use varnished cambric like Bjarney said. I like the silicone based stuff better it makes a real nice connection.

I also have done a bunch of internal motor connections with varying types of compounds and tapes. (Stator compound and Fuse a flex) if your interested in hearing about them let me know.

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