NEC 210.4(B) vs the IECC 505.2.2.2

[chris kennedy]

I just completed another job falling under the above codes and had an interesting observation. I have three ?" EMT's leaving a lighting control panel with 3 circuits each at 9 to 10 amps each. I opted to run a grounded conductor for each circuit rather than handle tie. These raceways are noticeably warm to the touch. Lets figure I have around 60A flowing on the conductors per raceway. Had I opted for one grounded conductor and ties I would be looking at 40A or less in each raceway.

I just found this interesting as the IECC wants me to conserve energy yet by my choice of application of the NEC I'm creating more heat, increasing the resistance, and wasting energy. I actually wasted wire also.

End.

 

[Dennis Alwon]

I did the same thing about two years ago. I ran individual neutrals to three lighting circuits rather than a MWBC. The conduit was very warm to the touch.

I am not sure how this works because you are wasting energy but not using more wattage. So does the power company actually have to produce more electricity for this situation? Where does the lose come from?

 

[chris kennedy]

I am not sure how this works because you are wasting energy but not using more wattage. So does the power company actually have to produce more electricity for this situation? Where does the lose come from?

By the time I had finished typing I had forgotten where I was going with that, you summed it up.

 

[Smart $]

I did the same thing about two years ago. I ran individual neutrals to three lighting circuits rather than a MWBC. The conduit was very warm to the touch.

I am not sure how this works because you are wasting energy but not using more wattage. So does the power company actually have to produce more electricity for this situation? Where does the lose come from?

With some of the newer electronic ballasts, especially the ones that cover a wide range of input voltages with just a single set of leads, the wattage of the load is the same... but the wattage of the entire circuit is higher due to voltage drop (I?R losses).