When we have parallel sets of service entrance conductors, that exceed 1750MCM per phase at the main service equipment, are we required ONLY to use the maximum main grounding electrode conductor size of a 3/0cu / 250MCM Alum, or would we be required to apply 250.24 (c)(1)-sum of conductors per phase X 12.5% to size it ?
Main grounding electrode conductor sizing
- Thread starter LPELEC1
- Start date
- Status
When you look at 250.24 (C) (1) & (2), I belive the 12-1/2% would apply only to your bonding jumper, unless you exceed 1100 (1750AL) in any one conduit, and not to your grounding electrode conductors.
- Location
- Illinois
- Occupation
- retired electrician
3/0 is the largest grounding electrode conductor that is required by the code. 250.24 does not apply to grounding electrodes.
- Status