Part 2 of Article 700, Circuit Wiring. If I am designing an emergency distribution panelboard or even switchboard, which is fed from an emergency generator, it appears, according to the 08 NEC Article 700, Part 2, that the distribution breakers in this panelboard or switchboard need to be physically separated. It seems that this is also the case in the 05 NEC however it really wasnt that apparent until Ive researched the 08 NEC Handbook. (which now has some pretty descriptive diagrams that are not in the 05 NEC Handbook)
Ive seen many installations over the past several years that have not followed these guidelines.
In a hospital environment, say you have Critical, Life Safety, Equipment Branches then several other optional stand-by loads, this switchboard would basically need to be individual, free standing sections for each feeder overcurrent protection?
What if each load is say, 100 amp overcurrent protection, this will be a pretty expensive distribution line-up.
What also makes this more confusing is the buss diagrams in NEC 517 for Hospitals. Those diagrams appear that each branch is on a common buss with no physical separation between branches.
Was it the intent in the 05 NEC Article 700 to have physical barriers between each circuit breaker in a emergency generator distribution panelboard or switchboard?
Is this even really possible if you have a wall mounted panelboard installation? I dont think so, which will basically have contractors resorting to a wireway with a bunch of gutter taps feeding circuit breakers in enclosures. (Which in my opinion seems to have more chance of faults with multiple taps in a wireway than simpy having breakers in a panelboard)?
Ive seen many installations over the past several years that have not followed these guidelines.
In a hospital environment, say you have Critical, Life Safety, Equipment Branches then several other optional stand-by loads, this switchboard would basically need to be individual, free standing sections for each feeder overcurrent protection?
What if each load is say, 100 amp overcurrent protection, this will be a pretty expensive distribution line-up.
What also makes this more confusing is the buss diagrams in NEC 517 for Hospitals. Those diagrams appear that each branch is on a common buss with no physical separation between branches.
Was it the intent in the 05 NEC Article 700 to have physical barriers between each circuit breaker in a emergency generator distribution panelboard or switchboard?
Is this even really possible if you have a wall mounted panelboard installation? I dont think so, which will basically have contractors resorting to a wireway with a bunch of gutter taps feeding circuit breakers in enclosures. (Which in my opinion seems to have more chance of faults with multiple taps in a wireway than simpy having breakers in a panelboard)?
