MV Cable Ground In Manhole

[Alwayslearningelec]

Has anyone ever done this in a manhole? How is the heck is the bond of the #4 ground wire in the manhole attached to the 5kv triplexed EPR cable. They actually show it as 3 separate conductor but it's in face one cable. Has anyone done this before.

Also what about the cable to manhole cover? Welding cable?

 

[Julius Right]

According to NESC/2007 Part 3: Safety Rules for Underground Lines
314. Grounding of circuits and equipment
B. Conductive parts to be grounded
Cable sheaths and shields (except conductor shields), equipment frames and cases (including padmounted devices), and conductive lighting poles shall be effectively grounded. Conductive-material ducts and riser guards that enclose electric supply lines or are exposed to contact with open supply conductors of greater than 300 V shall be effectively grounded.
EXCEPTION: This rule does not apply to parts that are 2.45 m (8 ft) or more above readily accessible surfaces or are otherwise isolated or guarded.
However, I never grounded the manhole entrance lid.

 

[Alwayslearningelec]

Thanks. But how the heck would one bond a wire to a cable sheath?
Tough to interpret that exception. So the grounding wouldn't apply to manhole?

 

[Julius Right]

I think the cable shield grounding is required when, in order to reduce the induced voltage up-built in shield and the single grounding point is some where in the middle distance or if the cable system is sectioned and grounded [as per IEEE 527].

 

[Julius Right]

Sectionalizing and grounding -and cross bonding if it is required-as per attached sketch

 

[Julius Right]

Sorry.The actual name of IEEE it is IEEE 575 [it is not 527 of course].