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Joined: Nov 2002
Posts: 456
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I think it is to protect the inside of the building in the event of a fault in the feeder.

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Joined: Jan 2003
Posts: 4,391
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As indestructible as RMC seems it can be eaten up quickly (vaporized) by service conductors faulting inside it.

When I weld I can cut holes through metal as thick as RMC with under 125 amps.

Service conductor may have 1000s of available amps, it is possible that even 2" encasement is not enough.

Don R (A moderator here) got to watch RMC burn back quite a way when service conductors faulted inside.

Bob


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: May 2003
Posts: 2,876
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e57 Offline
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iwire, today they're calling it 30'! I get a different answer every time! We have gotten ok'ed at 40, depends on the mood in the air. After all other options are exhausted.

So yeah, it's back to the drawing bourd for the "Designer" who is making his big move toward archetecture. He now needs an engineer to devise as way to power it. They'll have to remove steel to allow a shorter path. Or, re-engineer to hold encasement. Or, the bite the bullet and we do it my way and underground we go... This requires two retaining walls removed, re enginneered, and replaced. The owner is going to flip out!


Mark Heller
"Well - I oughta....." -Jackie Gleason
Joined: Jul 2004
Posts: 625
S
Member
e57,

Some of these underground contractors have gear where they can drill a bore sideways, underneath stuff like retaining walls.

My impression is that, in general, it's cheaper to use these direction drills than it is to tear up and replace concrete. I've seen them use these machines to drill under the sidewalk to install fiber, and, in another case, to drill under the street to replace a water-service lateral.

That might work for your situation. (I don't have pointers to any contractors. The machine I saw drilling to install the fiber was made by Ditch Witch, if that's of any help.)

[This message has been edited by SolarPowered (edited 07-15-2004).]

Joined: May 2003
Posts: 2,876
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e57 Offline
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Yeah those directional drilling rigs are hip. Unfortunately due to the grade, (super steap!) not advisable. And, the walls need to be done eventually. Don't think they'll hold a rig like that! Just don't think they were planning to do it now.

Did a walk thru with the designer/arch... It went like this...

Can we put there? NO!
There? NO!
There? NO!

He just didn't understand workspace, or the ten other codes guiding entry and service location.


Mark Heller
"Well - I oughta....." -Jackie Gleason
Joined: Jan 2002
Posts: 1,457
E
Member
E, if it were me I would tell them I have to follow code. No exception. Give them the code compliant options, disconnect here, or here, pick one. Even if the inspector said go ahead and run 30' through the building with no overcurrent protection there is no way in hell I would do it.

Joined: May 2003
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e57 Offline
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Yeah, I'm not into it either...

Unfortunatley, the building has to get fed somehow. It's not ever a question of where it will go at this point. It all comes down to a design without fore-thought as how it would function. And, I get to make it work, being caught in the middle of the Arch, and Inspector. My loyalty to the later! The only reason I even call about items like this, is for CYA purposes.

The inspector called it at 30', so over-head is out. I needed 38' for that. So under-ground we go.

As for following the code, I don't vary, and won't let anyone else lead me to. That is something I am very aggressive about. (something that gets me in trouble sometimes, but I don't care.) As by the end of this, the Arch will have a $50K past buget edjucation about where, and how services are done. The next one will be built around the service...


Mark Heller
"Well - I oughta....." -Jackie Gleason
Joined: May 2003
Posts: 2,876
E
e57 Offline
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Up-date on that job...
They found someone to do it! (38' through the building) And the rest of the job at half the price too!

Good riddin's!


Mark Heller
"Well - I oughta....." -Jackie Gleason
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