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What is better for a ground system - THW or THWN?

What is better for a ground system - THW or THWN?

What is better for a ground system - THW or THWN?

(OP)
All i find on the two is this:



THW (5) 75¡C 167¡F 90¡C 194¡F
DRY & WET LOCATIONS SPECIAL APPL. WITHIN ELECTRIC DISCHARGE LIGHTING EQUIPMENT LIMITED TO 1000 OPEN-CIRCUIT VOLTS OR LESS, (SIZE 14-8 ONLY AS PERMITTED IN SECTION 410-31).
MOISTURE AND HEAT-RESISTANT THERMOPLASTIC



THWN (5) 75¡C 167¡F DRY AND WET LOCATIONS


Is there a real benefit of one over the other with regard to buried ground system?

RE: What is better for a ground system - THW or THWN?

Personally, I'd use bare for a buried ground system.

RE: What is better for a ground system - THW or THWN?

(OP)
I'm told they can't due to catholic protection and other reasons.

RE: What is better for a ground system - THW or THWN?

The whole point is ground contact. Insulated conductors aren't so hot in that arena.

RE: What is better for a ground system - THW or THWN?

When faced with a choice such as this, I generally use the cable type that is in stock locally. That is unless there will be a lot of buried electric discharge lighting equipment. And I echo davidbeach's comments.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: What is better for a ground system - THW or THWN?

Look up ufer ground if you're trying to avoid soil contact.

Best to you,

Goober Dave

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RE: What is better for a ground system - THW or THWN?

The THW insulation will be thicker than the THWN and more resistant to physical damage, but not sure if there is any real difference in the resistance to ground in a buried installation over time.

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