grounding vs lightning 1

[bshamad]

we are installing 130 kW motors on a roof top of cooling plant . these motors are fed from VFDs that are contained in MCC panel. We connected earthing cable (yellow/green) from the MCC earthing busbar to each motor body. should we connect the lightning grid on the roof to the motors. i am afraid this will drive the lightning strike into the electrical system!

 

[dpc]

No. Keep the down conductors separate from the equipment grounding conductors.

Your lightning arrester rods need to be higher than your motors.

David Castor

http://www.cvoes.com

 

[bshamad]

this is what i was thinking.
thanks