Refeeding and splicing existing wires that are in concrete encase conduit

[Tainted]

I am upgrading the electrical room and removing existing service switches. The existing service switches feed concrete encased conduits below.

I will refeed the concrete encased conduits with a new switchboard with service switches.

I want to put the switchboard behind the conduits where the conduits sweep up from the concrete. The problem is the conduits will impede the clearance of the switchboard.

Is there any easy way to get rid of the sweep and just make a handhole? How hard would it be to dig and make a underground splice box to reconnect all the wiring?

 

[LarryFine]

Do you know which direction they turn as it compares to where you wish they emerged?

 

[Tainted]

Do you know which direction they turn as it compares to where you wish they emerged?

Don’t know unfortunately. The electrician and I were both scratching our head today trying to figure out and trace where it was going.

There are 9 conduits underground 3 per service switch

 

[LarryFine]

You may have to chop up some concrete just to see.

If you commit to doing so, you can reroute as needed.

Do you have enough headroom to build up the floor?

 

[Tainted]

You may have to chop up some concrete.

Do you have enough headroom to build up the floor?

I want to avoid building up the floor. Even if I did build up the floor I would still have to reconnect the feeders in the concrete encase conduit and splice them.

How does one chop concrete like this? I never seen it done to be honest

How would someone know how deep to go? Because they might accidentally cut the conduit underground

 

[Fred B]

Don’t know unfortunately. The electrician and I were both scratching our head today trying to figure out and trace where it was going.

There are 9 conduits underground 3 per service switch

An underground tracer will locate each. Like the greenlee 501

 

[infinity]

If those old RMC's have been in the earth for a long time don't be surprised if you dig them up and find not much left of the old metal. IMO the only way to estimate and design this is to start with removing a small section of the floor to see what you're dealing with.

 

[Tainted]

If those old RMC's have been in the earth for a long time don't be surprised if you dig them up and find not much left of the old metal. IMO the only way to estimate and design this is to start with removing a small section of the floor to see what you're dealing with.

I think they are 60 years old. How long do conduits underground last?

 

[Tainted]

If those old RMC's have been in the earth for a long time don't be surprised if you dig them up and find not much left of the old metal. IMO the only way to estimate and design this is to start with removing a small section of the floor to see what you're dealing with.

If I want to get rid of those sweeps, do I need a floor mount splice box in handhole?

 

[infinity]

If I want to get rid of those sweeps, do I need a floor mount splice box in handhole?

That would be a good solution. Cut the elbows off and nipple into a pull box. From there continue underground to the new location.

 

[Tainted]

That would be a good solution. Cut the elbows off and nipple into a pull box. From there continue underground to the new location.

What kind of box handhole should I get? I don’t think it’s an off the shelf product based on how the existing conduits are laid out


If I have the handhole in front of the new switchboard, would that be a 110.26 issue? Reason I ask is because if someone removed the handhole cover, then there will be a giant opening in front of the new switchboard

 

[JoeStillman]

Why not put a pull box on the floor on top of the pipes and mount your switchboard on top of the pull box?

 

[zbang]

How does one chop concrete like this?

Probably use a diamond saw to cut sections of the slab, then a jackhammer to break up the pieces. Unfortunately, it gets messy, both doing the work and dealing with whatever you find under the slab (including water and ancient oil leaks).

 

[infinity]

Why not put a pull box on the floor on top of the pipes and mount your switchboard on top of the pull box?

The switchboard is getting move back so the conduits, if left in their original location, will be in front of the new switchboard.

 

[Tainted]

Why not put a pull box on the floor on top of the pipes and mount your switchboard on top of the pull box?

Wouldn’t that violate 110.26, what’s the max height that a switchboard can be off the floor?

See infinity’s post. But i may consider this option if i exhaust my options

 

[jim dungar]

Wouldn’t that violate 110.26, what’s the max height that a switchboard can be off the floor?

See infinity’s post. But i may consider this option if i exhaust my options

Switchboards can be any height you want, as long as an appropriate work platform is constructed in front of them. You may be thinking of the maximum height to an OCPD handle of 6'7".

 

[Tainted]

Switchboards can be any height you want, as long as an appropriate work platform is constructed in front of them. You may be thinking of the maximum height to an OCPD handle of 6'7".

I don’t think a platform is suitable for this place. It’s also an obstruction of egress, someone can trip and fall

 

[electrofelon]

I don’t think a platform is suitable for this place. It’s also an obstruction of egress, someone can trip and fall

In their existing location, and if they stay, how far in front of the switchboard will these conduits be?

 

[Tainted]

In their existing location, and if they stay, how far in front of the switchboard will these conduits be?

About 2 feet. In NYC, if service is 1000kVA or more, service switchboard with service disconnect needs to have 5 feet of clearance

 

[electrofelon]

About 2 feet. In NYC, if service is 1000kVA or more, service switchboard with service disconnect needs to have 5 feet of clearance

Do you know that those are 90s sticking out of the concrete, or could there be a straight piece on top of a 90?