Dry type transformer fed from Outside Lines, BIL Rating Surge Arrestor 1

[bdn2004]

We have several hundred feet of 600V insulated aluminum cable installed on an overhead pole line feeding a pad mounted 480V-120/240V dry type transformer. There is a static line on the top of the pole line. It has been suggested to put station class arrestors at the last pole down to the transformer because the dry type transformer only has a 10kV BIL level. Why? And how do you determine the right arrestor?

 

[alehman]

I'm not aware of low voltage station class arrestors. You might try something like this:

http://www.macleanpower.com/products/item.asp?ITEM_ID=2236

 

[Marmite]

I've never seen surge arrestors applied to low voltage overhead lines. In the UK a cable with a length greater than around 150 yds would be deemed to be self protected and not require surge arrestors.
Regards
Marmite

 

[tommom]

Try Current Technologies (Danaher Power). I think their equipment is one of the top 3 with Liebert and LEA. You can look up the expected exposure in IEEE 1100 (Emerald Book) based on your location and expected frequency & severity of thunderstorms.

https://currenttechnology.com/

 

[alehman]

Note that there is a difference between a lightning arrestor and a transient voltage surge suppressor. The NEC has slightly different installation requirements as well.