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romex
part of unit 4 in the NEC
Question | Answer |
---|---|
non-metallic sheathed cable is arcticle | 334 |
sizes of romex | #14-#2 2-4 conductors |
NMB | flame retardant, moisture resistant, 90 degrees |
NMC | flame retardant, moisture resistant PLUS corrosion and fungus resistant, 90 dgrees |
general rule #1 staples boxes | staples at maximum 12inches from box if it is clamped if not then a maximum of 8inches away, must have 1/4 of the sheath in the box |
floor rule | must be smaller then 6/2 or 8/3 |
general rule #2 staple lengths | must be a staple every 4 1/2 feet |
general rule #3 wire bends | cable can not be bent in a radius less then 5 times the diameter of the wire |
general rule #4 floor shield in floor | cable must have some sort of shield if it goes more then 6inches through a floor |
general rule #5 wire in box rule | must have 6inches in the box or atleast 3inches sticking out of the box |
uses not permitted for romex | 1. as a service enteracne cable 2. hazardous locations 3. places of assembly 4. embedded in concrete |
use permitted for romex | 1. residential purposes 2. multi family dwelling of type 3,4,5 construction ex. hotels resort condominium 3. other structures if concealed within a 15min fire rated material 4. exposed or concealed 5. in any dry locations |
NMC permitted for | 1. exposed or concealed locations 2. dry, moist, damp, corrosive loctions 3. masonry walls 4.covered by 1/16th sheet metal |
neutral rules | can be reduced when l-l (line to line load) in a 240 volt circuit |
neutral can be reduced by? | 70% |