Ground Wire Insulation

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BruceM

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Hi All,

Is there a listing or code requirement for providing an insulated ground wire, as they are offered in both bare and insulated. What application would a insulated ground wire be required/acceptable for that a bare ground wire would not be or vice versa? If they are interchangeable, why would the manufacturers or installers spend the extra money / resources to provide insulation if they are not required to?
 
Are you referring to equipment grounding conductors (EGC's)? Insulated conductors are easier to pull in a raceway. You can use either bare or insulated. The only condition that I can think of is the case of isolated grounds (there may be others), obviously bare would defeat the purpose.

Welcome to the Forum.
 
BruceM said:
Hi All,

Is there a listing or code requirement for providing an insulated ground wire, as they are offered in both bare and insulated. What application would a insulated ground wire be required/acceptable for that a bare ground wire would not be or vice versa? If they are interchangeable, why would the manufacturers or installers spend the extra money / resources to provide insulation if they are not required to?
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Terminology is important
Please look up definition of ground in Art 100
Or, as Mike Holt once said, “what color is it and what does it do?”
And sometimes insulated is used as it was on the truck.
There is a difference in stranding between insulated and bare copper. Bare would be better for a wire that goes to a ground rod, IMO, as the strands are larger
 
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If you had a cathodic protected facility, you would use an insulated conductor
 
The reason that I asked my question is....
The contractor is installing Belden VFD Cable with copper tape shielding from the VFD to the cooling tower motor junction box. Belden's installation instructions indicate to remove the outer jacket and copper tape shield, de-cable the exposed conductors and grounds, take the 3 #8 bare copper grounds, twist them together, shrink wrap them and then to shrink wrap the entire cable assembly. The contractor did not twist together or shrink wrap the grounds & the assembly per the mfg installation instructions. Is there a code reason that this should be done or based on the comment below, wouldn't it be prudent to shrink wrap them to protect the customers investment in the event of a ground fault.

I saw this comment from Tom Baker in the Insulated vs Bare Ground Wire thread.

Tom Baker 11-11-18 "One recommendation for an insulated EGC was in either the IEEE green book or Soares, namely use an insulated EGC so in the event of a ground fault the insulation would help from damaging the adjacent conductors from the heat generated in the EGC."
 
That’s a mfg requirement, and if there is a issue with drives, Beldon can rightly say was not installed correctly
Your code reference is 110 3 B
Ground is not the correct term, look up definition.
what you describing sounds like a shield, what I said in earlier post may not apply
 
tom baker said:
That’s a mfg requirement, and if there is a issue with drives, Beldon can rightly say was not installed correctly
Your code reference is 110 3 B
Ground is not the correct term, look up definition.
what you describing sounds like a shield, what I said in earlier post may not apply
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Hi Tom,
Thank you for your comment and sorry about getting the term incorrect regarding ground Ancora Imparo :)
Is this the IEEE section that you referring to regarding insulated EGC?

9.4 Thermal Withstand

9.4.1 General

When metallic conduit is used as an EGC, no special considerations are necessary for fault duty of the
conduit. When a copper conductor is used to supplement the metallic conduit or where a conductor is
necessary, such as in nonmetallic conduit, the design should be evaluated to ensure that the conductor
thermal rating is not exceeded. Exceeding the thermal rating can have two effects:
a) Increased temperature can damage the insulation either of the EGC in case it is insulated or of
adjacent phase conductors, especially when the grounding conductor is bare, rendering them unusable following fault clearing.
 
BruceM said:
The reason that I asked my question is....
The contractor is installing Belden VFD Cable with copper tape shielding from the VFD to the cooling tower motor junction box. Belden's installation instructions indicate to remove the outer jacket and copper tape shield, de-cable the exposed conductors and grounds, take the 3 #8 bare copper grounds, twist them together, shrink wrap them and then to shrink wrap the entire cable assembly. The contractor did not twist together or shrink wrap the grounds & the assembly per the mfg installation instructions. Is there a code reason that this should be done or based on the comment below, wouldn't it be prudent to shrink wrap them to protect the customers investment in the event of a ground fault.
Click to expand...
You might be better off using a bonding type gland. I don't think they are UL listed though, at least not yet.
 
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