Lugs....

[Open Neutral]

(Another topic no one ever told me in school decades back that an EE would be asked someday....)

A machine shop I hang out at [1] needs to add a small single phase panel after an unfused disconnect that feeds 3ph loads now. The electrician doing the work states the rub is the lug limit. He's not aware of a legal way to terminate more conductors than those there.

My knowledge of the NEC in such an area is roughly “Lasciate ogni speranza, voi ch’entrate!”. If this were not a power system, but something inside a box with various microcontrollers, etc. I'd be thinking of insulated terminal strips, or a soldered Y splice covered with heat shrink, etc.

But it is something NECish. Which if any way should I point the electrician toward to finding an approved solution?



[1] More fun and less likely to get me in trouble than bars -- more toys, fewer calories, and we make fun things.

 

[petersonra]

Polaris connectors?

Power distribution block?

 

[Open Neutral]

Polaris connectors?

Power distribution block?

Thanks; I have sent the Polaris lead to the electrician.....

 

[kwired]

If there is no room to make splices then somehow adding an additional enclosure to make the splices in may be necessary.

 

[Open Neutral]

If there is no room to make splices then somehow adding an additional enclosure to make the splices in may be necessary.

We have lots of room.
What are the rules we must follow on splices? [3-4 pieces of #3 stranded CU]

I'd assume we'd solder such and cover with heat shrink.

 

[ActionDave]

We have lots of room.
What are the rules we must follow on splices? [3-4 pieces of #3 stranded CU]

I'd assume we'd solder such and cover with heat shrink.

No solder.

 

[SceneryDriver]

Absolutely do not solder the connections! Use these:

https://www.grainger.com/product/34...6677!&ef_id=WMrXvwAAADSAZ8SS:20170512122846:s


SceneryDriver

 

[dkidd]

110.14 (B) Splices. Conductors shall be spliced or joined with
splicing devices identified for the use or by brazing, welding,
or soldering with a fusible metal or alloy. Soldered
splices shall first be spliced or joined so as to be mechanically
and electrically secure without solder and then be
soldered. All splices and joints and the free ends of conductors
shall be covered with an insulation equivalent to that of
the conductors or with an identified insulating device.

 

[Smart $]

...A machine shop I hang out at [1] needs to add a small single phase panel after an unfused disconnect that feeds 3ph loads now. ...

We have lots of room.
What are the rules we must follow on splices? [3-4 pieces of #3 stranded CU]...

Are they truly splices... or is this a feeder tap situation. If so, 240.21(B) applies.

 

[Besoeker]

Do any of you use these for power cables?

They are compression lugs applied with a crimp tool. We'd normally use heat shrink sleeving to cover the end of the conductor and the crimped part of the lug.

 

[kwired]

Are they truly splices... or is this a feeder tap situation. If so, 240.21(B) applies.

Call the connection whatever you want, it is still a connection to another conductor. 240.21(B) only tells us what size of conductor we can use in relation to overcurrent protection in certain circumstances, nothing about how to make the connection though.

 

[Smart $]

Do any of you use these for power cables?

They are compression lugs applied with a crimp tool. We'd normally use heat shrink sleeving to cover the end of the conductor and the crimped part of the lug.

Since the advent of polaris-type splice connectors it seems like not many are using these to make splices... but crimping on and bolting several together is just as viable a splice method IMO.

 

[kwired]

Do any of you use these for power cables?

They are compression lugs applied with a crimp tool. We'd normally use heat shrink sleeving to cover the end of the conductor and the crimped part of the lug.

Pretty good chance the OP's disconnect he wants to tie into has factory installed mechanical set screw type lugs. Many are designed or arranged that they are not replaceable with a different design or type - especially in the 200 amp or less device ratings, and is also pretty common (in 200 amp or less devices) that they are designed to only accept one conductor per terminal.

 

[Smart $]

Pretty good chance the OP's disconnect he wants to tie into has factory installed mechanical set screw type lugs. Many are designed or arranged that they are not replaceable with a different design or type - especially in the 200 amp or less device ratings, and is also pretty common (in 200 amp or less devices) that they are designed to only accept one conductor per terminal.

So you've never made a splice by crimping on two or more of these terminals and bolting them together? Not even to make up a motor peckerhead?

:blink:

 

[kwired]

So you've never made a splice by crimping on two or more of these terminals and bolting them together? Not even to make up a motor peckerhead?

:blink:

Not to land in a disconnect or on a circuit breaker that has a compression screw lug, especially that lug is not screw/stud fastened and basically is non removable.

 

[Open Neutral]

110.14 (B) Splices. Conductors shall be spliced or joined with
splicing devices identified for the use or by brazing, welding,
or soldering with a fusible metal or alloy.......

vs:

Absolutely do not solder the connections!

&

No solder

I'm confused.

 

[Smart $]

vs:


&


I'm confused.

It's there in case someone wants to do it one of those ways... but that does not mean you should.

 

[kwired]

vs:


&


I'm confused.

soldering some 12 AWG conductors together isn't nearly as difficult of a task as soldering some 3 AWG conductors likely will be.

 

[Open Neutral]

It's there in case someone wants to do it one of those ways... but that does not mean you should.

And I must ask, why don't I want to use a soldered splice? To my thinking, it's the sturdiest, more reliable solution.

Obviously you learned gentlemen do not think so, so please educate me.
I learn by asking people smarter than me both dumb and undumb questions....

 

[Besoeker]

soldering some 12 AWG conductors together isn't nearly as difficult of a task as soldering some 3 AWG conductors likely will be.

Soldering these conductors might not have been a practical proposition.............