greenspark1
Senior Member
- Location
- New England
Hi. I have a commercial building with a large outdoor motor on a concrete pad. The facility is properly grounded and has a ground ring around the whole building. The motor is powered by three phases and has a wire type EGC. The concrete pad of the equipment has its own bonding jumper that ties into the ground ring.
My concern is that this bonding jumper for the concrete pad creates a parallel path for ground current to flow. This means that ground current will flow on the ground ring back to the service ground, ultimately bypassing the building's electrical system and not tripping any ground fault breakers. While adding a ground for this equipment pad might seem like a good idea, I feel that it actually compromises the electrical safety of the facility. I would prefer for the ONLY ground to be through the EGC.
This would be especially true if there was a concrete pad for a non-electrical piece of equipment, like a plastic tank. Bonding the pad will completely bypass the electrical system.
Thoughts & comments?
My concern is that this bonding jumper for the concrete pad creates a parallel path for ground current to flow. This means that ground current will flow on the ground ring back to the service ground, ultimately bypassing the building's electrical system and not tripping any ground fault breakers. While adding a ground for this equipment pad might seem like a good idea, I feel that it actually compromises the electrical safety of the facility. I would prefer for the ONLY ground to be through the EGC.
This would be especially true if there was a concrete pad for a non-electrical piece of equipment, like a plastic tank. Bonding the pad will completely bypass the electrical system.
Thoughts & comments?