Wyoming Division IAEI Annual Meeting/Seminar 2003 Code Panel Questions Answers in BOLD, using 2002 NEC

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1 Wyoming Division IAEI Annual Meeting/Seminar 2003 Code Panel Questions Answers in BOLD, using 2002 NEC 1. Patient bed locations in healthcare facilities. Does the insulated equipment grounding conductor have to be bonded to each box in the metal raceway system back to the panel? Yes , , (A & B) 2. In a five-story building can I run a new emergency circuit up through the elevator shaft from the basement to the top level? No, only wiring associated with the elevator is allowed The outside jacket of THHN-THWN is damaged during installation. Do these conductors have to be replaced prior to acceptance? No, nylon jacket is for physical protection, unless the conductors are exposed to gasoline or oil, and then the nylon jacket is required. UL White Book 4. An electrician has installed two conduits from fixtures to the branch circuit panel. In each conduit there 11 # 12 THHN conductors that are considered current caring conductors. What are the rated amps for the conductors and what size breaker must protect the conductors?? 15 Amps, derated according to As a state inspector, should I refuse to accept 15 amp receptacles installed in a building where the engineer specified 20 amp receptacles? State inspectors are only charged with enforcing the National Electrical Code and other related documents 6. In healthcare facilities, do the emergency panel and normal power panel feeding the same area have to be bonded together? Yes, Can you define where, on a building, a wet location will be, as opposed to a damp location? Yes, definitions using Article In Article 410.4(D), lighting fixtures of this type are not allowed in a zone of the bathtub and shower area. Are there any rules for location of other lighting fixtures not mentioned in Article 410.4(D)? No, ask your AHJ, 110.3(B) 9. Arc-fault circuit interrupter protections are required for dwelling unit bedrooms. What determines what rooms will be used for bedrooms? Ask your AHJ, most look for a clothes closet, although there is no definition in NEC or Building Codes

2 10. Can a person run numerous home runs of NM-B cable into a flush mount breaker panel, through a 2 PVC made adapter mounted in the top of the enclosure? The individual KO s will not be used, as all home runs will run through the adapter. No, 312.5(C) exception 11. Why does the equipment grounding conductor in a feeder to a mobile home have to be insulated? Because the Code says so. Possibly for additional protection 12. Are the ends of the conductor used in a ground ring required to be spliced together, in an approved manner, to meet the definition of a ring? Yes, (A)(4) 13. Are there any sections of the code you would be able use to enforce voltage drop requirements for residential applications other than the recommended fine print note FPN #4? No 14. What constitutes the placement of a seal-off where the conduit comes out of the concrete floor in an automobile garage? 511.3, 511.4, 501.5(A) 15. How does an inspector enforce , Mechanical Execution of Work? That is up to the AHJ 16. A 750 KW generator set generating 480 volts three phase with a 1000 amp fused disconnect feeds a remote manually operated 4 pole nema 6 contactor that then feeds a bank of Wye configured 300 KVA buck boost transformers with a secondary of 14.4 KV. There are fused cut outs on the utility primary and an air brake disconnecting all three ungrounded conductors. The system grounded conductor (neutral) remains solidly connected to the secondary of the buck boost transformers. What is the proper method of grounding and bonding the transformers pots and high voltage secondary and the grounding electrode system created for the generator? , , overhead 4 times per mile Should there be any concern about the phase angle of the generator and the utility knowing that the system ground is solidly connected between transformer secondary and the utility ground system (neutral)? Phase angle is not an issue Is this covered by the NEC or the NESC? The municipality owns the generator and the utility owns the power distribution system. NEC is responsible at the Service Point 17. What is the minimum service requirement for a horsey corral with stock water heater and who knows what else?? 60 amp, (D)

3 18. Is a service rated disconnect required for the horsey corral?? Yes, , (C) 19. Would Art (A)(1) Exception: ( or structures where conditions of maintenance and supervision ensure that only qualified persons service the installation) would this ever apply to a residence, if the owner only permitted professional tradesman to work on the dwelling? No, only in industrial or commercial 20. An existing mobile home has a 200 amp panel with a 200 amp main breaker. It is fed from a 200 amp breaker in a pedestal. They are attaching a pole barn type structure to one end of the mobile home to be used as a garage. They are installing a 100 amp panel in this structure. Is it required to feed this panel from the mobile home panel with a 4 wire feeder or can it be fed from the pedestal with a 3 wire feeder and establish a ground at the panel? 3 or 4 wire, up to the AHJ, When the reinforcing bars in the footers and wall of a basement is not made available by the contractor, is it a requirement of the code for the contractor to make it available? Up to the AHJ, (A)(3) 22. Are the smoke detector outlets required in the bedrooms required to be on the AFCI? Yes, (B) 23. In healthcare facilities, do the emergency panel and normal power panel feeding the same area have to be bonded together? Yes, May the building steel be used as the equipment grounding conductor from the disconnect of an optional standby generator to the transfer switch ground bus, when the only grounding electrode available is the building steel? No, NM-B requires physical protection when passing through floors. Is type ENT allowed as a nonmetallic raceway as required in 336-6(b)? No, (B), Can the re-bar in the concrete pillars, used for the footers of a manufactured home, be utilized for the Ufer electrode? If it meets the requirements of (A)(3) 27. The measurement of a wall is inclusive of the corners and change of direction in residential receptacle location requirements. Why is a boxed in column with 12 sides that measure 48 with all sides taken into consideration not required to have a receptacle? Up to the AHJ, (A)(1&2) 28. Conductors from a fire pump service to the pump controller are located within a onehour rated room and the service is installed on the outside wall of this room. Can these conductors be installed in EMT without any fire rated protection other than the room? Yes, Article 358

4 29. Does MC or AC have any limit for the number of bends or length between boxes? No 30. A master bedroom has a wet bar with a small sink. What applies, GFCI, AFCI, or both? Both, 210.8(A)(7), (B) 31. Can the grounded conductor, required by NEC , to be installed and bonded at each service disconnecting means also be bonded to a gutter ahead of the service disconnecting means? Yes, (A)(1) 32. Less than six feet of metal clad cable is installed from fixture to fixture. Does the cable need additional support at the fixtures or does it meet the exception of fixture whips? No, (B)(2) 33. In a single family dwelling, a metal raceway can pass through a return air duct. Can a steel box for a switch or plug be mounted within this space? No, (B) 34. Can the grounding conductor for a telephone service be routed around the house for bonding to the electrical service? Yes, installed according to (A)(4) 35. NEC requires interrupting ratings to be based on available fault currents at the terminals of the equipment. Are let thru values based on the up, over and down method still valid for designing a safe system Yes 36. Where does the equipment-grounding conductor begin? Where does the grounding electrode conductor end? (In relation to the service disconnect and over current protection) and the definition of Grounding Electrode Conductor. Read Article 100 (Definitions) 37. Can SER aluminum cable be installed in an underground conduit from a house to feed a garage panel? If rated for wet locations, In bonding a grounding electrode conductor to a metal raceway, does a rigid coupling with a NM cable (Romex) connector threaded into it and clamped to the conductor work for a choke fitting? No, not listed for the application 39. Can the receptacle requirements for countertops, islands and peninsulas be satisfied by the installation of Plug mold at the bottom of the cabinets? Yes, if installed according to (C)(5) 40. We have a project, in a KOA campground, for wiring small, one-room cabins with receptacles for portable cooking stoves and lighting outlets. There is also a table and bed in this room. Is arc-fault protection required because of the sleeping area? No, (B)

5 41. How is the grounding and bonding for a trailer mounted generator used for a pumping station backup power system installed to meet NEC requirements? An office building has exit corridors that contain night lights (luminaires that are never off) Can the required exit and egress lighting be connected to the night light circuit? Is this addressed in the NEC or it just cowboy logic? Yes, if no switch in the circuit, May MC Cable be installed in PVC buried under a concrete slab? Yes, (A)(7), The NEC requires the circuits in a panel to be marked. When an old panel, that has no circuits marked, is converted into a sub-panel, does the NEC require the existing circuits be traced out and labeled in the old panel? Up to the AHJ, A 1600 amp, 3 phase, 208 volt main switchgear has four-400 amp breakers and two 400 amp spaces. The designer wants to tap from the bus bars with one set of 500 THHN cu conductors to a 400 amp, 250 volt fusible disconnect with 400 amp fuses which will feed a 208/480 volt step-up transformer. The 480 volt secondary of this transformer has 3/0 cu THHN conductors to a 200 amp 600 volt fusible disconnect. It then runs 600 to a 480/208 volt step-down transformer. Does this installation comply with the NEC? No, unless the directions allow the buss to be tapped 46. An 800-amp 120/208-volt feeder consists of two sets of 500 KCM cu conductors per phase in non-metallic conduits. Is it necessary to install equipment grounding conductors in each conduit? What size grounding conductors are required? Yes, full size in each raceway (1/0), (F) 47. A rural residence has a utility owned pole and meter. The contractor is required to set a disconnect switch with over current under their meter. Underground conductors extend from this disconnect 150 to and thru the basement of the home for a main breaker panel located in the garage. The inspector required another disconnect, at the house, before the conductors entered the basement citing NEC and Doesn t the disconnecting switch on the utility pole satisfy these code requirements? AHJ KCM copper feeds a 400 amp CT Enclosure, and then feeds two 200 amp panels. Is the bonding conductor sized for the 500 KCM cu or the 3/0 cu feeding each 200- amp panel? Both, , (C) 49. Are in-use covers required on 15 & 20 ampere, 125-volt receptacles installed on construction temporaries? Yes, 406.8(B)(1)

6 50. Branch circuit conductors enter section #2 of a two section panel, run through the nipple between the panels and terminate into section #1 s breakers. The breakers are numbered from one to 84. Is this code compliant? No, 408.3, 408.3(A)(3) 51. In a theatre, would THHN-THWN wire be acceptable to be connected to a solid state dimmer? No, (F) 52. How do I determine if a 1000-gallon propane tank that is located 1 Meter from an electrical service and panel is safe? If the area is classified as hazardous, the equipment must be listed and installed according to the classification (B) 53. Does the NEC code allow the grounding of an outlet or junction box via the grounded conductor (neutral)? Yes, , Where an isolation transformer is installed in an operating room, do the conductors from that transformer have to be tested for dielectric strength after the entire system has been installed? Not according to the NEC, , NFPA 99 will require it 55. At a medical building, Article requires both the service and feeders to GFI protected according to and At this building doctor s offices are attached to the building. These offices are exam room and offices. Is GFI protection still required for the feeders that supply the panels at these offices?? The service is 480/277 volt with 3000 amp main breaker and the feeders are supplied from 480/277 volt 600 amp breakers. Depends on the use of the building, if part of the Hospital, Yes, A panel with a Class I Div. I, Group C rating is installed in an area of Class I, Div I, Group A, atmosphere. Is this acceptable? No, 500.8(A & B) 57. What is the conductor fill of seal-off fittings in Class 1 division 1 locations? 25% unless identified, Is PVC allowed to be installed in plenum areas? No, (B) 59. Is it code compliant to install amps? Breakers in a meter main combo of a 200 amp. service, feeding amp sub panels with no main disconnecting means for the service? Yes, if the computed load does not exceed the rating of the service, (A) exception #3 60. Is a counter-top cook top required to have a disconnect for a permanently connected appliance as in NEC ? Yes, (B)

7 61. There is a remodel with existing panel that is filled to capacity with branch circuit spaces. One circuit breaker has 2 branch circuits (one is general purpose outlets and the other is smoke detector circuit) terminated under the lug. Is this allowed by code if there is no mention of number of conductors allowed under the terminal lug by the manufacturer? No, unless identified for two conductors 62. There is a stairway up to a 12 x 12 loft area and a guardrail along the edge of the room leading to another room. Would the space along the guardrail be considered wall space of that room or a hallway leading to the other room? Yes, (A)(3) 63. A receptacle installed outdoors in a wet location (20A-125V) for servicing AC equipment. Must this receptacle comply with (B) (1) or with 406.8(B) (6)? 406.8(B)(1), 406.8(B)(6) not in 2002 NEC 64. What type luminaries (fixtures) are allowed when installed directly above and less than 8 (eight) feet from the top rim of a residential hydro massage bathtub? Those listed in and 410.4(D) 65. What are the minimum size conductors, disconnect amperage rating, for a residential garage with 2 circuits? 30 amps, (B) 66. When an Intrinsically Safe System is installed in accordance with the manufacturer s instructions, does the installation affect the classification of the area? No, Is there a requirement for separation of low voltage and medium voltage wire raceways or cable systems? Yes, (A) & (B)(4), Please reference NEC Article (B). Branch circuit over current devices may not be restricted from access to tenants (occupants) in multiple occupancy buildings. Does this apply if they are only accessible to authorized management personnel? If it complies with (B) exception 1 & Why does Article (A) limit the number of overcurrent protection devices on the supply side, of a lighting & appliance branch-circuit panelboard? 70. How long is a Temporary Journeyman license good for?? 71. When the authority having jurisdiction approves the use of conductors or equipment that is not identified, labeled, or listed, does the responsibility of use fall on him? Yes, 90.4

8 72. What is the official NEC interpretation for kitchen? There is none. 73. NEC states that dry type transformers must be separated from combustibles by a fire resistant, heat insulated barrier. Does a standard sheetrock wall meet the barrier requirement? No 74. Does NM cable need to be kept away from heating ducts and/or plenums? What is the temperature rating of the external jacket on NM cable and the conductor insulation? No, Sheath is rated at Do field cut conduit threads for outdoor installations need any special coating applied to them? Yes, 300.6(A) 76. A service meters ampacity for a fire pump is within code. Will it handle the locked rotor current of the motor that it is well over the rating of the meter? Yes 77. Does the NEC allow a sub-panel in a crawl space of a single-family dwelling? No, unless it is readily accessible, 408.8(A) 78. A facility receives power at the property line and feeds overhead to all the buildings on the property. The owners want to install a pole-mounted transformer, with appropriate high voltage cut outs to protect the transformer, and then feed directly from the transformer secondary to four poles mounted meters below. There are no disconnecting means at the pole meters. These meters will feed four buildings near the poles. The meters are owned by the property owners and will be used to separately bill the building tenants. Is this a code conforming installation 79. Can the wiring for a receptacle be run through and beyond fluorescent fixtures if it is on the same circuit? No, A detached garage is fed underground with USE conductors from the house. Can the USE conductors run through the house floor joists to the panel? No, must be installed in a raceway, (B)(4) 81. Can a cord be used to supply power from the junction box on a pole to the luminaries? Yes, 400.7(A), (B) 82. Can a plug fuse, without a disconnect switch, be used as the required disconnect per ? No, When a homeowner is adding a bedroom addition and the existing panel manufacturer does not make an AFCI breaker, does he still have to comply by changing out the panel or adding a sub-panel to match an AFCI breaker that is manufactured? Yes

9 84. On a separately derived system (transformer) can the transformer enclosure be bonded to the grounded conductor if the grounding electrode conductor is installed at the secondary disconnect? No, unless it is non-metallic raceway, Can a 120-volt receptacle be installed in the same box with a 277-volt switch? Yes, if a barrier is installed, 404.8(B) 86. Does the receptacle, that is required within 25 of the roof top equipment, need a inuse cover when it is only used while servicing equipment? Yes, 406.8(B)(1) 87. The local inspector requires all parallel service conductors to be the same length. Does this mean that all the conductors of all the phases and neutrals have the same length or just the conductors for each phase? Just each phase, NEC requires a lighting outlet in attics if the spaces are used for storage. The roof trusses are not designed for any loads other than the snow and sheetrock loads. The attic access is required, by the building code, when the attic space height is 30 or greater. Can we require a light in this space for possible storage when the building system is not designed for it? Doesn t the light encourage storage? The light is not required and would probably encourage storage. 89. A 277/480-volt service protects underground conductors feeding two well pump motor locations. A ground rod is installed at the service location and at each well pump motor location. The ground rods are bonded to the grounded conductors at each location. The inspector required a second ground rod at the service location citing NEC Don t the other two ground rods satisfy this requirement? No 90. When the interior of a recessed lighting fixture is sprayed with paint or texture spray, May it be cleaned with a non-abrasive soapy water solution? No 91. I used a two gang NM box for the range receptacle in a house. Why don t they make the holes for cable big enough for range cable? I had to break out the divider between the cable openings to get the cable into the box. The inspector said it was a violation because it wasn t clamped. Is he right? Boxes are available with larger KO s, Is the working space required in front of a panel, which located on a wall beside a door, violated when the door is open and is in front of the panel? When the door is closed the space is in compliance. In Wyoming this is a code violation. 93. A hallway, less than 10 in length, has a wall inset for an optional counter cabinet. If a counter cabinet is installed does it require a receptacle or this area still classified a hallway?

10 Depends on the use. AHJ 94. Do all of the equipment grounding conductors, required to be connected together, in a box need to have 6 of free conductor length or just the pigtail that is required for the device? All do, I installed four parallel feeders with A-phase in one PVC conduit, B-phase, C-phase and the neutrals each in separate PVC conduits for ease of terminations. The inspector said that each PVC conduit must contain a set of A, B, C, and neutral conductors. I believe NEC (I) exception #2 allows my method of installation. Am I correct? Yes 96. Cables to be used with directional boring must be approved for the purpose. Can these same cables be continued as direct burial conductors within a trench where the directional boring ends? Must be listed for both uses. 97. Are splices permitted in raceways with removable covers such as plug mold? Yes, Independent support wires are provided, from the structure, to fixtures in non- rated suspended ceilings as is required by the Uniform Building Code. Are the fixtures still required to be securely fastened to the T-grid? Yes, (C) 99. Some Gas log appliances have a 120-volt receptacle located behind a hinged door for access to the control section at the bottom of the appliance. It is used for an optional accessory fan. Does this receptacle need to be on the AFCI circuit when the gas log is in a bedroom? Yes, Can the switch for an outdoor light that is not on an AFCI circuit be installed in a bedroom? Yes,