Wireway size

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hardworkingstiff

Senior Member
Never mind, my problem stemmed from looking at this as a wireway (and a pull box) when it probably is actually an auxiliary gutter. I was looking at (2) 3" conduits and (9) 2" conduits in a row.

3*6=18
3+(2*9)=21
21+18=39" required height.

Inspector said it really wasn't a pull box and didn't need to be calculated that way.

Reading a bit I have come to the conclusion it is an auxililary gutter and we just need to satisfy 366.56(A), table 312.6(A), and we can ignore 366.58(B) since the conductors enter and go to a splice point so they don't leave and it's not considered a pull box.

Anything I missed or didn't think about?

Thanks,
 

DARUSA

Senior Member
Wireways or Gutters

Wireways or Gutters

The maximum size conductor in a wireway must not be larger than that for which the wireway is designed 376.21.

The maximum number of conductors in a wireway is limited to 20% of the crosssectional area of the wireway 376.22

Splices and taps must not fill more than 75% of the wiring space at any cross section 376.56.
 

DARUSA

Senior Member
Wireways or Gutters

Wireways or Gutters

Where conductors are bent within a metal wireway, size the wireway to meet the bending radius requirements in Table 312.6(A), based on one wire per terminal 376.23.
 

DARUSA

Senior Member
Wireways or Gutters

Wireways or Gutters

More than 30 currentcarrying conductors in any crosssectional area of the wireway, adjustment factor is required.
 

augie47

Moderator
Staff member
overlooking the size issue for the moment, why isn't the raceway NEMA3R like all the other equipment ?
 

hardworkingstiff

Senior Member
Why do you ask, adding something to this?
It's a 3-phase service feeding 50-amp receptacles (shore power for boats). The wiring on the docks was replaced a couple of years ago and now they are getting bigger boats in the marina they are finally understanding what I told them back then, "you need single-phase service".

So the job will consist of changing the service delivery. Since the (9) 200-amp disconnects are 1-phase, then it appears to be easy to bring in new service conductors, CT cabinet and service disconnect to re-feed the 200-amp disconnects.

The issues:

There is a 200-amp 1-phase meterbase and service for the buiding just around the left corner.

The owner needs the docks and building power on separate meters.

AHJ will not allow 2 points of delivery of the same voltage to the building.

Not enough room to bring together 1000-amp service disconnect, meter and CT cabinet in this same location.

AHJ also said that engineering drawings would be required to replace this service.
It turns out I can buy a 1000-amp MB panel with (9) 200-amp breakers for a couple of dollars less than I can a 1000-amp enclosed service disconnect. Seems to make sense to bring the conduits into the panel through the bottom. Install a 200-amp meterbase and service disconnect to re-feed the building panel. Let the service conductors come into a CT cabinet, run the conductors for the 1000-amp panel through CTs and come out of the CT cabinet with conductors that are not metered by the CTs to feed the 200-amp meterbase to re-feed the building.

Engineer and PoCo don't seem to agree. It would clean up that mess a bit, and get rid of a rusting gutter and rusting enclosures for the existing 200-amp breakers. I sense that others think I'm trying to make more work than necessary.
 
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