Generator Cables

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natfuelbill

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Is it acceptable per NEC or UL to use welding cable for connection of a generator (mobile or portable) to premise wiring? Welding cable appears to be what is typically used.
 
Re: Generator Cables

Most welding cable that is used has some other type of listing on the insulation that is typically acceptable, such as RHH or RHW. Without some type of recognized insulation type found in the NEC, it shouldn't be used.
 
Re: Generator Cables

all insulation should have a type stamped on it.
The reason welding type cable is used is because it has a higher ampere rating (allowing smaller cable to be used), is much more flexible, and withstands cuts due to its rubber insulation.
 
Re: Generator Cables

Another thing that shouldn't be overlooked is how the cable should be terminated. The lugs must be listed for it of you must use compression ring tongue terminals and bolt the connection.
 
Re: Generator Cables

lawelectric,
The reason welding type cable is used is because it has a higher ampere rating (allowing smaller cable to be used) ...
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Where do you find this higher rating? How does that rating work with the NEC rules?
Don
 
Re: Generator Cables

Ron,
Most welding cable that is used has some other type of listing on the insulation that is typically acceptable, such as RHH or RHW.
Click to expand...
I don't know if I would say that most welding cable has this type of listing. I know that some does, but I have never actually seen any of it.
Don
 
Re: Generator Cables

Hey Don..
I would refer to Table 400-5(B).
Again, I have no idea what cable type he was refering to, but this is what I have used in past stanbye genset installs.
I have used both SCE and PPE
 
Re: Generator Cables

lawelectric,
Welding cable is not in that table. Type "W" is "Portable Power Cable", not welding cable. Also that table is effectively a "free air" table and its ampcities are in line with those in Table 310.17 for single conductors in free air.
Don
 
Re: Generator Cables

Don't know which code book you're looking at. I am in Cal., which enforces the 1999 NEC.
Table 400-5(B) clearly lists "W". As I stated the type I have used and didn't know what he was asking for in particular, He stated "welding" cable, but didn't EXACTLY refer to type "W". On an installation stand point, you certainly wouldn't lay 80' of THHN in the dirt of a construction sight, which means you would be running it in conduit, which means the amp rating would be lower. I know everbody likes to prove everyone else wrong, not sure why you are trying so hard on me. But it's fun. (besides, I have only been wrong 454,975 times before) Going to work, but looking forward to your response. Have a great day!
 
Re: Generator Cables

We use a lot of DLO cable which I believe is also listed as RHW-2. Extra flexible and carries a higher amp rating. UL listed at 2kV and CT rated.
 
Re: Generator Cables

Brad,
We use a lot of DLO cable which I believe is also listed as RHW-2. Extra flexible and carries a higher amp rating.
Click to expand...
It is not all dual listed so you have to be sure you get the dual listed type if you want to avoid a red tag.
Again with the ampacity, it is not really higher as the published ampacities are based on free air and 90?C. The published ampacities for DLO very closely match the 90?C column in Table 310.17 until you get to the kcmil sizes. At that point the DLO ampacities are a bit higher than what is shown in the table, but the DLO cables have 5% to 7% more copper than the standard kcmil sizes. Examples: 250kcmil is 262.5kcmil in DLO and 500 is 535.5.
Don
 
Re: Generator Cables

Thank you all for your comments on this subject.
What is are you referring to with the "dual listed" phrase?
 
Re: Generator Cables

Originally posted by natfuelbill:
Thank you all for your comments on this subject.
What is are you referring to with the "dual listed" phrase?
Click to expand...
Means the insulation meets specs for more than one type, as THHN or THWN or RHW or USE.
 
Re: Generator Cables

What is are you referring to with the "dual listed" phrase?
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The cables that are only listed as DLO or welding cable cannot be used in NEC applications. Some of these cables are listed as DLO and RHW or welding cable and RHW. These "dual listed" cables can be used for NEC applications.
Don
 
Re: Generator Cables

Originally posted by don_resqcapt19:
Brad,
We use a lot of DLO cable which I believe is also listed as RHW-2. Extra flexible and carries a higher amp rating.
Click to expand...
It is not all dual listed so you have to be sure you get the dual listed type if you want to avoid a red tag.
Again with the ampacity, it is not really higher as the published ampacities are based on free air and 90?C.
Click to expand...
Right on both counts. I just assumed ;) since it was a portable genset, it was a free air application.
 
Re: Generator Cables

Professional test taker ;) Just kidding - I design electrical and some mechanical systems. Mostly commercial properties and some substation work for our bigger properties. Started out as a pipe bender wiring apartments in New Mexico 35 years ago.
 
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