Lightening Protection for a building
Lightening Protection for a building
(OP)
Recently I took a position as a facility operations manager and have observed many of the lights being blown during storms and lightening for the past two weeks. Also have had to reset many of the pumps and air handlers in the building, and had one pump burn up. The lightning suppression system in the building is a bonding system, and is not isolated from the building. Wouldn't this direct the lightning through the structure and the equipment. My discipline is not electrical but I would imagine that the lightening protection would be better if insulators were installed on the rods and isolated from the building..
Any suggestions appreciated..
Any suggestions appreciated..





RE: Lightening Protection for a building
The lightning rods and down conductors can be insulated from the building structure, but must be bonded to the building grounding system at some point, per the NEC.
In the case of direct lightning strike on the building, the lightning probably traveled 50,000 feet through the air, so any insulators installed would be of minimal value anyway.
RE: Lightening Protection for a building
RE: Lightening Protection for a building
Lighting is a high current/high voltage discharge that ocurrs over a long path. As such, even a nearby lighting strike produces a lot of EMP (electromagnetic pulse) that radiates and can be picked up by the longer wires in a building. Building wiring routed through conduit is shielded by the conduit and is low impedance and unlikely to have a significant voltage induced on it. However, wires for computer connections, alarms, control circuits, etc are usually strung around in a building without conduit and with no more than a foil wrap for shielding. These can pick up the radiated pulse (especially if they are long) and channel it right down to the interface circuits at either end - frying them or upsetting the control electronics.
Are you air handlers and pumps controlled by lower voltage control lines? Did your pump burn up because the controls turned it on with no load, or with a valve in the wrong position? Or are you power items being truly directly overloaded by the strike getting on your building power?
RE: Lightening Protection for a building
RE: Lightening Protection for a building
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Regards
RE: Lightening Protection for a building
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RE: Lightening Protection for a building
I have contacted the contractor to test and make sure that I have adequate surge protection on the incoming power, to all my equipment.
Thanks again...
RE: Lightening Protection for a building
Just one point Tomfitz (apologies if you think I am a pedant, but spelling and grammar in engineering is important to me) there is no e in the middle of lightning.
RE: Lightening Protection for a building
RE: Lightening Protection for a building
RE: Lightening Protection for a building
RE: Lightening Protection for a building
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