Re: harmonics in a 208V service
Bob,
I admit that I regularly specify double neutrals for feeders out of a power distribution unit (PDU) to the power panel (RPP), as I do not know what kind of the load the client will have in the future. I do not specify IG circuits anymore (for the last 5-6 years or so).
I have found problems in older sites that were designed for a smaller load density, which is now being used for higher.
For example, who would have thought 10 years ago, when designing a datacenter, that some of the loads would be 10-12kW per server rack. Now we are happy that we oversized at that time.
For that same reason, I try to design a project with spare underground conduits, and redundancy, because you never know .....