Electrician Talk banner
1 - 20 of 28 Posts

·
Registered
Joined
·
385 Posts
Discussion Starter · #1 ·
I'm just starting a job and in the spec. it states to come out of the slab with pvc coated grc. But from there I have to use rigid aluminum. Is it o.k. to connect the two different metals together? It also says in the spec to keep the aluminum isolated from other metals with plastic sleeves or plastic coated hangers. What are your all thoughts?
 

·
Banned
Joined
·
15,674 Posts
We did a job where the specs stated the use of rigid conduit. We did a transition from PVC to aluminum. Not sure how you would transition from rigid to rigid aluminum?:001_huh:
 

·
Registered
Joined
·
8,050 Posts
I would think the continuity of ground would supersede the engineers bright idea but that's just me
 

·
Registered
Joined
·
8,050 Posts
BBQ said:
I assume there will be a copper EGC in the conduit.
True but would the two different conduits be allowed to be mechanically isolated per the NEC?
 

·
Registered
Joined
·
12,167 Posts
I agree with your concerns.

What kind of project is it that they want you to use aluminum conduit?
 

·
Registered
Joined
·
385 Posts
Discussion Starter · #13 ·
I agree with your concerns.

What kind of project is it that they want you to use aluminum conduit?
It's a water pumping station. I use it quite a bit in water and waste water industry. Price is pretty comparable to grc but it's sucks to work with. Come home covered in black oil everyday.
 

·
Registered
Joined
·
12,411 Posts
I'm just starting a job and in the spec. it states to come out of the slab with pvc coated grc. But from there I have to use rigid aluminum. Is it o.k. to connect the two different metals together? It also says in the spec to keep the aluminum isolated from other metals with plastic sleeves or plastic coated hangers. What are your all thoughts?
The bare threads are now, not coated. The oxide on the surface of the aluminum will cause a reaction.
 

·
Registered
Joined
·
1,948 Posts
As long as it's not in a corrosive environment, it will probably be okay to transition steel to aluminum. I wouldn't want to rely solely on the conduit for a ground path, though
 

·
Registered
Joined
·
76 Posts
buddhakii said:
It's a water pumping station. I use it quite a bit in water and waste water industry. Price is pretty comparable to grc but it's sucks to work with. Come home covered in black oil everyday.
It's great to work with. Weighs almost nothing.... You're going to be oily anyways threading GRC all day
 
1 - 20 of 28 Posts
Top