Lightning Protection

[Jed057]

Anyone,

If I have AHU(For HVAC made from steel) on the flat roof of substation so please advise that we would need Air Terminal on the roof or we just use AHU instead and connect to bare copper directly to earth.

Thanks

 

[ScottyUK]

In my experience most AHUs are largely thin sheet metal held together with pop rivets and self-tapping screws. What steel structure there is usually appears to be coated in rust accelerant. Not something you would want to deliberately attract a lightning strike to. On top of that, most AHUs contain at least a fan and motor, possibly a pre-heat battery heater too, and both common sense and probably your LP code would rule against attracting lightning strike to equipment connected to your LV system.

I'd fit a proper air terminal connected to a suitable earthing system, assuming you're not already in the area shadowed by another larger structure (e.g. a transmission tower or adjacent building).


----------------------------------

If we learn from our mistakes I'm getting a great education!