Multi Conductor Cable to THHN Transition

[Sean.Day72]

I have a situation where we are running XHHHN multi conductor cable (MC cable has 3#4/0, #4G) in cable tray on the roof of a building. After penetrating the roof with the MC cable we need to transition to standard THHN building wire in conduit. My suggestion to provide a box with Polaris splice in it to accomplish this. Is there any better way to do this? I hate splicing branch circuits but this is a unique situation where we can't run conduit through the building, only on the roof.

 

[LarryFine]

Is the conduit run short enough that it's viable to strip the sheath from that portion of the cable?

You mentioned three Hs but no Ws. Is the cable's conductors' insulation wet-rated?

 

[electrofelon]

Just curious is the MC coated? Or are there covers on the tray allowing non coated MC?

I agree with Larry, stripping the MC and pulling thru the conduit is good if it's not too far.

 

[roger]

Why not use the MC for the whole run?
I would have no concern with making a splice. For price comparison check PDBs verses Polaris lugs.

 

[electrofelon]

Why not use the MC for the whole run?
I would have no concern with making a splice. For price comparison check PDBs verses Polaris lugs.

Yeah. Perhaps the aesthetics committee didn't want exposed cable? OP said " this is a unique situation where we can't run conduit through the building, only on the roof" is that a typo and he meant "cable"?

 

[don_resqcapt19]

My preference is always for a compression splice than a mechanical one.

 

[Sean.Day72]

Yes typo. MC cable on the roof is Jacketed XHHW-2 , 3#4/0, #4G to be exact. (wet rated, sun light resistant jacketing) . Photo below . Compression splice inside a box to transition to EMT conduit seems to be the play. I was just making sure I wasn't violating a code section.

 

[LarryFine]

Can you just sleeve the exposed portion?