Section 408.41

[spurlockda]

Hello everyone, hope this finds you all well.

My question revolves around the 408.41 section. I understand the literal and context of the section but so I can completely understand it and finally commit it to memory I need to clear up the exception. I'm a new student so please bear with me.

The exception states: Grounded conductors of circuits with parallel conductors shall be permitted to terminate in a single terminal if the terminal is identified for connections of more than one conductor.

I understand the concept of the bus bar being identified by the manufacturer as being physically capable of containing more than conductor depending on gage but the concept of "parallel conductors" is where I'm foggy. I wonder in my mind if they are talking about the physical geometry of the neutrals routed within the breaker box or is the parallel concept due to electrical contexts?

My Chiefs in the Navy used to say I was dumber than a stump but I am a stump that can soak up a lot of knowledge. Can someone help this stump gain some more knowledge? Thanks!

 

[Dennis Alwon]

Parallel conductors are conductors used to increase the capacity of the run without having to use very large conductors. It is cheaper to run 2 runs of 3/0 copper than it is to run a 500 kcm or 600 kcm conductor. There are lugs made- usually double legs for this install. I believe there are single lugs that are also designed for 2 of these conductors.

 

[charlie b]

My Chiefs in the Navy used to say . . . .

Well, let an old retired Navy Commander and long time user of this forum say, "Welcome, and good luck with your new career." This forum is a great place learn.

 

[electricalist]

In a panel I THINK we can only put 1 grounded conductor under each space on the grounded bus, however if we use 2 grounded conductors as Mr. Denis stated we would need them to be under a lug rated accordingly. There are conditions for the size of conductors that can be ran in parallel.

 

[Henley]

From one Newbie to Another, Here is how I would interpret this (Going out on a limb though).
Most often parallel conductors are run to feed higher current sub panels, they are allowed to be formed from same length/same type conductors joined at both ends. The terminals therefore must be identified for multiple connections under the screw. BUT, in a case with low unbalanced Neutral loads, the Grounded Conductor required could be a single conductor, which still has to connect to the panels terminals. Therefore the exception to allow a single conductor under a termination identified for multiple.

I would hold out for a confirmation from someone more experienced. Welcome to the forum BTW !