Grounding of sub-transmission insulator bases

[stevenal]

RUS says if you have a ground wire running close by horizontal insulators, you should tie in the bases to prevent RFI. Is there any reason to tie in the bases of suspension insulators that are not so close to the ground wire? What's your practice? 69 and 115 kV. Thanks.

 

[bacon4life]

At 115 kV on wood poles we bond any hardware separate by less than 1 foot to prevent pole fires. I had not heard of bonding insulator bases to prevent radio frequency interference.

On a slightly related note, loose suspension hardware can cause RFI. One situation that can cause loose hardware is spans with uplift.

 

[stevenal]

Bacon,

You've heard of it now. See RUS 1724E-200 page 8-14. Makes sense from the pole fire perspective too. Consider an H-frame with suspension insulators with no uplift, though. No bonding here?

 

[bacon4life]

Thanks for the link. If the H-frame crossarm is conductive, it may need bonding where it attaches to the pole.