Caddy Pyramid system

[PCN]

We are hoping to use the new Caddy Pyramid 300 equipment supports for several 4" pvc conduits installed on a membrane roof.

My question is, how in the world to ground this?

One seperate conduit just to carry an equipment ground and terminate to a mechanical lug at each support? We might have 30 of these critters.

Any thoughts would be appreciated.

http://www.erico.com/products/caddypyramid300.asp

 

[cowboyjwc]

Why would you need to "bond" them?

 

[CIECO]

Maybe I am not to bright but I have used many of these and never thought of bonding them.

 

[PCN]

Why would you need to "bond" them?

I was thinking 250.110. Maybe I'm way off base. This is a new system (to me), we used to just use a 4X4 pt post for a sleeper.

My boss recommended bonding, he's the PE, I'm the peon. :grin:

 

[acrwc10]

I don't see those as likely to become energized. If they are you have a bigger issue with the pipe and insulation on the conductor.

 

[tkb]

Are you mounting steel conduit?
If so then that bonds them.

 

[PCN]

Are you mounting steel conduit?
If so then that bonds them.

No, it's PVC.

 

[LarryFine]

No, it's PVC.

Then, there's nothing likely to energize them. No grounding required.

 

[Split Bolt]

Ive used the 50 pound versions a lot. (never grounded them) Some for PVC & some for EMT. The 300# version looks pretty bulky. Do you have that much weight?

 

[Split Bolt]

Sorry, forgot my link:

http://www.erico.com/products/caddypyramid50.asp

 

[tkb]

No, it's PVC.

So are you using PVC straps?
I don't think that regular strut straps are good for PVC. They don't allow for movement.

 

[PCN]

So are you using PVC straps?
I don't think that regular strut straps are good for PVC. They don't allow for movement.

I was thinking these would work. I am very concerned about expansion though, the runs are about 65', in a region where temp changes 100 degrees from winter to summer.

http://www.unistrut.com/Browse/cat_detail.php?S=S06&P=P2600

 

[PCN]

Ive used the 50 pound versions a lot. (never grounded them) Some for PVC & some for EMT. The 300# version looks pretty bulky. Do you have that much weight?

There are seven runs of 4". 2 runs have 500's and 5 have parallel 350's.

 

[tkb]

Did you also derate for your height above the roof surface?

 

[PCN]

Did you also derate for your height above the roof surface?

Yes, we'll be a minimum of 12" above the roof which I believe is in the 17 degree adder range.

 

[LarryFine]

So are you using PVC straps?
I don't think that regular strut straps are good for PVC. They don't allow for movement.

With the blocks just sitting on the roof, I don't think that would be an issue.

 

[Split Bolt]

These things just sit on top of the roof membrane. They will move as the PVC expands and contracts.