Annual Conference
The 2023 annual Conference and Trade Show of the SD Electrical Council will be held in Sioux Falls, SD at the Best Western Plus Ramkota Hotel and Conference Center in Sioux Falls, SD April 14-15, 2023. More information will be posted on the Conference Registration page. Registration will open January of 2023.
Questions from the Inspector’s Code Panel at the 2022 Conference (answers follow lower on this page):
2022 SDEC code panel questions
1. Are receptacle outlets required to be installed above a built-in desk located in the living room of a dwelling unit?
2. We have a 277/480 V. system that is being converted to a 120/208 V. system. Can we re-use the existing 600 V. rated distribution equipment on the 208 V. system, assuming all fault current ratings are adequate?
3. I have a large commercial building needing a 2000 Amp service. Can I get a switchboard with two sections each with 3 – 400 Amp main breakers in each section?
4. Do all dwelling units now require the main breaker to be installed outside like with a meter-main combination panelboard?
5. If a NM-B support is used as listed, such as a Gardner Bender Multicable Staple Snapshot, is there a need to derate for bundling? For example, the packaging says each support can be used for (8) 12-2/G NM-B cables.
6. Is a Construction Meter/ Temp. Construction Service subjected to the same Grounding & Bonding requirements in Art.250 as a Permanent Service? i.e., Supply Side Bonding Jumper, Main Bonding Jumper, Grounding Electrode Conductor, from electrodes connected to the Grounded (Neutral) Conductor.
7. Is there a Code compliant way to connect EMT to a weatherproof junction box with threaded hubs?
8. I have been told that when I install a go-from (EMT to Type MC Cable) that the fitting has to be accessible or listed to be hidden, is that accurate? If so, why? What are the listing requirements to allow concealment for items such as EMT connectors or rigid couplings?
9. When must I use the table value instead of motor nameplate current rating?
10. Is it permissible to install LFNC underground for a feeder raceway from one structure to another such as a house to a detached garage?
11. Is it necessary to connect all the 125 Volt receptacles in a dwelling unit garage to the 210.11(C)(4) required 20-amp branch circuit or can we have additional, individual branch circuit-supplied receptacles for specific appliances, i.e.: central vac or freezer? Can there be other receptacle branch circuits rated 15 amps?
12. A 100-Amp feeder is installed with EMT using the raceway as an EGC, however both ends transition to flex or seal-tight for flexibility, would it be required to install an exterior bonding jumper sized based on the 100-Amp OCPD?
13. Section 210.8 (A)(1) GFCI protection for outlets in bathrooms. Once you have met the required 20-amp circuit can you add an additional 15-amp circuit to the bathroom as long as the receptacles are GFCI protected?
14. Is an individual branch circuit required for cord-connected range hood?
15. Is it a violation to hang a 10’ stick of rigid conduit to a 4″ square box that an exit sign is attached to without supporting the box at the exit sign?
16. Do commercial bathrooms wall mounted 1000w hand dryers require a disconnect?
17. What is the minimum size copper THWN conductor required to supply an air conditioner condensing unit with a minimum circuit ampere requirement of 23 Amperes? All terminals are rated 75° C.
18. The local REA is doing a remodel project in their business office they are
saying they do not need an electrical permit since they are a utility is this
true?
19. Does an electrical inspector have the authority to make the decision that an
installation might not meet the exact requirements of the code but in their
opinion provides an equal amount of safety?
20. As a general rule when do you have to use the 60-degree Column when
sizing a conductor?
21. Can an electrical room with a 1,600-amp service have the lighting for the
room only controlled by a motion detector.
22. Does the dedicated space requirements for electrical panels apply if the
panels are mounted outdoors?
23. I was written up for taping a black wire white, what size can I start taping
the grounded conductor.
24. I was talking to another electrician at the supply house and he said that
you now have to GFCI protect a dishwasher, is he correct?
25.I am wiring a 4-plex and wondering if I can take branch circuits for general
area security lights from the closest unit or do I need to have a house
panel.
26. I know that I must have a GFCI protected main for a 3,000-amp 480/277
volt service but is also true that any feeder of 1,000-amps or more also
needs GFCI protection?
27. I have this free-standing panel board with a 1600-amp main breaker, I
would like to bring all the A phase conductors through 1 conduit and so
on. I want to do this because I must wrap / lash the conductor because
of the high fault current can I do this?
28. I ran 3 sets of 500 KCMILL copper for the service conductors of a 1,200
Amp fused service disconnect and I was told that the wire is too small in
size, why is that?
29. Talking to others at the local supply house they were saying I can not
use 4/0 aluminum for a 200-amp service for a coffee house, is that true?
30. I was written up for having a 100-amp breaker protecting a feeder of #2 AL
SER cable for a sub panel in a new addition for a dwelling unit. I thought
that #2 AL is good for 100 Amps
31. Can you tell me where in the code it flat out says that you can only load a
circuit breaker 80% if the load on the circuit lasts longer than 3 hours?
32. Do you know where I can find the requirements of a metal box installed in
a firewall?
33. I have the style of four-square boxes that have combination 3/4″ and 1/2″
KO’S if I only use the 1/2″ KO’S do I have to install a bond bushing on a 277/480-vold system?
34. Is a plain old four-square box considered concrete tight?
35. Are there any questions you would like to ask any of us?
Here are the answers from the SDEC Inspector Panel:
2022 SDEC code questions key
Jeff L., Doug B., Jeff H., Dan S., Larry K.,
Jeff L.1. Are receptacle outlets required to be installed above a built-in desk located in the living room of a dwelling unit?
a. Maybe. It depends on how long the desk is and where other wall receptacles are placed in the room. A receptacle is required for every 12’ of wall space and within 6” of the beginning of every wall space.
b. 210.52(A)(1) and (A)(2)
(1) Spacing. Receptacles shall be installed such that no point measured horizontally along the floor line of any wall space is more than 1.8 m (6 ft) from a receptacle outlet.
(2) Wall Space. As used in this section, a wall space shall include the following:
(1) Any space 600 mm (2 ft) or more in width (including space measured around corners) and unbroken along the floor line by doorways and similar openings, fireplaces, and fixed cabinets that do not have countertops or similar work surfaces (Added in 2017)
Doug B.2. We have a 277/480 V. system that is being converted to a 120/208 V. system. Can we re-use the existing 600 V. rated distribution equipment on the 208 V. system, assuming all fault current ratings are adequate?
In general, yes. The equipment is rated for voltage up to the 480/277 volts indicated on the nameplate. Therefore, the spacings and dielectric aspect may find the equipment to be more robust than what may be required. The other aspect is that as voltage goes down for the same power the current goes up including available fault current. So again, as long as the equipment SCCR is sufficient for the available fault current and has a proper operating current rating, it should be suitable for use. The last consideration would be that any voltage sensing parts, such as voltage transformers for metering, would need to be changed. It would be highly recommended that additional markings be installed to indicate that the equipment is operating at 208/120 volts to prevent any confusion for someone seeing the equipment and “assuming” what the operating voltage is.
Jeff H.3. I have a large commercial building needing a 2000 Amp service. Can I get a switchboard with two sections each with 3 – 400 Amp main breakers in each section?
No. Changes to the six disconnect rule in 230.71(B) permit only one service disconnect per switchboard vertical section. There are a number of restrictions regarding installations with multiple service disconnects so I recommend spending some time studying this section of the code. Also, pay attention to the changes in 110.26(C) for entrance/egress from the working space requirements. 110.26(C)(2)(2) will requires entrance/egress from the working space on both ends when the combined disconnect ratings are 1200 A or more and over 6ft wide. Ref: 230.71(B)(3) and 110.26(C)(2)(2)
Dan S.4. Do all dwelling units now require the main breaker to be installed outside like with a meter-main combination panelboard?
ANSWER: See 230.85
No, what is required is a means to shut down power to the dwelling unit on the exterior of the building. This is identified as an Emergency Disconnect (for first responders – thus it is not about a shock or fire hazard protection) Therefore, the disconnecting means does not need to have overcurrent protection, it can be one of three items: it can be a meter disconnecting means, or a standard non-fused disconnecting means, or it could be the actual service disconnect (if the service is outside such as with a meter main, a separate emergency disconnecting means is not required)
Larry K.5. If a NM-B support is used as listed, such as a Gardner Bender Multicable Staple Snapshot, is there a need to derate for bundling? For example, the packaging says each support can be used for (8) 12-2/G NM-B cables.
No. These NM supports serve two purposes: they locate the cable far enough away from the edge of (most) framing members that physical protection (nail plates) is not required and they maintain spacing between conductors as required in 334.80.
Jeff L.6. Is a Construction Meter/ Temp. Construction Service subjected to the same Grounding & Bonding requirements in Art.250 as a Permanent Service? i.e., Supply Side Bonding Jumper, Main Bonding Jumper, Grounding Electrode Conductor, from electrodes connected to the Grounded (Neutral) Conductor.
ABSOLUTELY. Why wouldn’t you?
Doug B.7. Is there a Code compliant way to connect EMT to a weatherproof junction box with threaded hubs?
Yes. But in general conduit fittings for EMT (as well as FMC, LFMC, etc.) are only listed and suitable to use with a locknut through a sheetmetal enclosure. The threads on the hub are listed and suitable only for use with threaded conduit. The NPT threads have to meet an ASME standard whereas the conduit fittings for EMT are close but are formed and not machined. These have not been tested for grounding and bonding capability or for weather integrity for outdoor use. This is indicated in the UL guide information found in the UL Product iQ under the category DWTT which states:
Male threaded fittings provided with or without a locknut and intended for securement to boxes with threaded entries or fittings with internal female threads (e.g., hubs, conduit bodies, couplings) are provided on the smallest unit shipping carton with installation guidance to install into a box with a threaded entry or hub. See PRODUCT/CARTON MARKINGS below for additional information.
Nipples have only been investigated for use with locknuts.
Fittings with internal female threads (e.g., hubs, conduit bodies, couplings) have only been investigated for use with threaded rigid conduit.
There are EMT fittings from at least two manufacturers that I know of that are listed for use with either a locknut or to be threaded into threads on a hub, conduit body, or rigid coupling. Look at the product markings very carefully and these markings are on the box or the accompanying installation instructions.
Jeff H.8. I have been told that when I install a go-from (EMT to Type MC Cable) that the fitting has to be accessible or listed to be hidden, is that accurate? If so, why? What are the listing requirements to allow concealment for items such as EMT connectors or rigid couplings?
Answer: A “go from” for EMT to MC is a field combination of an EMT fitting, rigid coupling and an MC fitting. All the fittings may be Listed for specific wiring methods but not Listed as a single complete transition fitting. Rigid couplings have been Listed as part of Rigid metal conduit. If it has a Listing mark on the coupling then it has been Listed for use with Listed rigid metal conduit. UL Lists
RMC and couplings under the product category Rigid Ferrous Metal Conduit (DYIX). Male threaded fittings have only been Listed for use with a lock nut unless the smallest shipping carton identifies it as Listed for securement to a threaded hub.
Section 300.15 Boxes, Conduit Bodies, or Fittings — Where Required.
Fittings and connectors shall be used only with the specific wiring methods for which they are designed and listed.
Where the wiring method is conduit, tubing, Type AC cable, Type MC cable, Type MI cable, nonmetallic-sheathed cable, or other cables, a box or conduit body shall be installed at each conductor splice point, outlet point, switch point, junction point, termination point, or pull point, unless otherwise permitted in 300.15(A) through (L).
F) Fitting.
A fitting identified for the use shall be permitted in lieu of a box or conduit body where conductors are not spliced or terminated within the fitting. The fitting shall be accessible after installation, unless listed for concealed installation.
In order for the fitting to be Listed for concealed installation, the complete fitting would have to be a Listed transition fitting under the UL Product category Conduit Fittings (DWTT) or EMT Fittings (FKAV) or MC Cable Fittings (PJOX). You can find the guide information and Certifications/Listings for these product categories on UL Product iQ at UL.com/piq and enter DIYX, DWTT, FKAV or PJOX at the keyword search.
Dan S.9. When must I use the table value instead of motor nameplate current rating?
For the feeder or branch circuit conductors, for the short circuit and ground fault protective device, and for the disconnect ratings, the Table values apply unless there are special motor cases. The nameplate applies for the overload protection.
Reference 430.22 and 430.52 that sends the user to 430.6(A)(1). In 430.6(A)(1)
430.6(A)(1) Table Values.
Other than for motors built for low speeds (less than 1200 RPM) or high torques, and for multispeed motors, the values given in Table 430.247, Table 430.248, Table 430.249, and Table 430.250 shall be used to determine the ampacity of conductors or ampere ratings of switches, branch-circuit short-circuit and ground-fault protection, instead of the actual current rating marked on the motor nameplate. Where a motor is marked in amperes, but not horsepower, the horsepower rating shall be assumed to be that corresponding to the value given in Table 430.247, Table 430.248, Table 430.249, and Table 430.250, interpolated if necessary.
Motors built for low speeds (less than 1200 RPM) or high torques may have higher full-load currents, and multispeed motors will have full-load current varying with speed, in which case the nameplate current ratings shall be used.
Larry K.10. Is it permissible to install LFNC underground for a feeder raceway from one structure to another such as a house to a detached garage?
Answer: Yes, if installed in accordance with Article 356 and Listed for direct burial and outdoor use. UL Lists LFNC under the product category Flexible Nonmetallic Conduit, Liquid-tight (DXOQ) that can be found on UL Product iQ at UL.com/piq and entering the category code DXOQ at the search field.
Jeff L.11. Is it necessary to connect all the 125 Volt receptacles in a dwelling unit garage to the 210.11(C)(4) required 20-amp branch circuit or can we have additional, individual branch circuit-supplied receptacles for specific appliances, i.e.: central vac or freezer? Can there be other receptacle branch circuits rated 15 amps?
No. Additional garage receptacles are allowed per the provisions of 210.11. It states clearly that “at least one” 120 volt, 20 ampere branch circuit shall be installed to supply receptacle outlets required by 210.52(G)(1). That requirement is for a receptacle outlet for each vehicle bay. This required circuit can not have any other outlets
Doug B.12. A 100-Amp feeder is installed with EMT using the raceway as an EGC, however both ends transition to flex or seal-tight for flexibility, would it be required to install an exterior bonding jumper sized based on the 100-Amp OCPD?
Yes, a bonding jumper would be required under the specified conditions. And because the OCPD exceeds the maximum allowable value for the flex or seal-tight to be considered an EGC, a bonding jumper of some sort will need to be installed in order to insure the EMT is connected to an equipment grounding conductor. 250.86 and 250.118(4), (5), (6).
Jeff H.13. Section 210.8 (A)(1) GFCI protection for outlets in bathrooms. Once you have met the required 20-amp circuit can you add an additional 15-amp circuit to the bathroom as long as the receptacles are GFCI protected?
Maybe. If the 15-amp circuit does not serve the sink/ vanity receptacle outlets in the bathroom. A 15-amp circuit could serve other loads, but any additional receptacle outlets are required to be on 20-amp circuits. Reference 210.11.
Note that any and all receptacles in a bathroom must be GFCI protected per 210.8(A)(1).
Dan S.14. Is an individual branch circuit required for cord-connected range hood?
Yes, 422.16(B)(4) allows a range hood or microwave-range hood combination to be cord and plug connected meeting 5 specific requirements. One of those requirements stated in 422.16(B)(4)(3) is that the range hood be supplied by an individual branch circuit.
Larry K.15. Is it a violation to hang a 10’ stick of rigid conduit to a 4″ square box that an exit sign is attached to without supporting the box at the exit sign?
Yes, 344.30(A) requires RMC to be securely fastened within 3ft of an outlet box, junction box, cabinet, conduit body, or other conduit termination. 344.30(B) would permit support at intervals not exceeding 10ft but that doesn’t state the installation can be without any support.
Jeff L.16. Do commercial bathrooms wall mounted 1000w hand dryers require a disconnect?
Yes. The disconnecting means may be the branch circuit switch or overcurrent device may serve as the disconnect if it is within sight of the hand dryer or is capable of being locked in the open position in compliance with 110.25. Reference 422.31
Doug B.17. What is the minimum size copper THWN conductor required to supply an air conditioner condensing unit with a minimum circuit ampere requirement of 23 Amperes? All terminals are rated 75° C.
Table 310.16 – #12 AWG = 25 A but section 310.15(B) and Table 310.15(B)(1) must be applied for ambient temperatures greater than 86F/30C
Jeff H.18. The local REA is doing a remodel project in their business office they are
saying they do not need an electrical permit since they are a utility is this
true?
No, they need a permit, only installations directly involved in generation and
transmission are exempt from the NEC Section 90.2(A)(4)
Dan S.19. Does an electrical inspector have the authority to make the decision that an
installation might not meet the exact requirements of the code but in their
opinion provides an equal amount of safety?
The authority having jurisdiction an electrical Inspector may waive specific
requirements in this Code or permit alternative methods where it is assured that
equivalent objectives can be achieved by establishing and maintaining effective
safety. Section 90.4
Larry K.20. As a general rule when do you have to use the 60-degree Column when
sizing a conductor?
As a general rule 100 amps and less using # 14 through #1 conductors. Section 110.14 (C)(1)(a)
Jeff L.21. Can an electrical room with a 1,600-amp service have the lighting for the
room only controlled by a motion detector.
The lighting for the room cannot be only controlled by automatic means. Section 110.26 (D)
Doug B.22. Does the dedicated space requirements for electrical panels apply if the
panels are mounted outdoors?
Yes, they do just like they do if the panel was located indoors. Section 110.26 (E)(2)
Jeff H.23. I was written up for taping a black wire white, what size can I start taping
the grounded conductor.
You can tape a conductor #4 and larger. Section 200.6
Dan S.24. I was talking to another electrician at the supply house and he said that
you now have to GFCI protect a dishwasher, is he correct?
Yes he is, GFCI protection shall be provided for outlets that supply dishwashers.
422.5(A)(7) rated 150 volts or less to ground and 60 amperes or less, single- or 3-phase, shall be provided with Class A GFCI protection for personnel. So, this would apply to commercial and residential for cord and plug or hardwired.
Larry K.25.I am wiring a 4-plex and wondering if I can take branch circuits for general
area security lights from the closest unit or do I need to have a house
panel.
You need to have a house panel. Branch circuits installed for the purpose of
lighting, central alarm, signal, communications, or other purposes for public or
common areas of a two-family dwelling, a multifamily dwelling, or a
multi-occupancy building shall not be supplied from equipment that supplies an
individual dwelling unit or tenant space. Section 210.25 B
Jeff L.26. I know that I must have a GFCI protected main for a 3,000-amp 480/277
volt service but is also true that any feeder of 1,000-amps or more also
needs GFCI protection?
Yes, it is, a feeder of 1,000-amps or more with a line to neutral voltage of 150
volts or more needs GFCI protection. Section 215.10
Doug B.27. I have this free-standing panel board with a 1600-amp main breaker, I
would like to bring all the A phase conductors through 1 conduit and so
on. I want to do this because I must wrap / lash the conductor because
of the high fault current can I do this?
Yes, where a single conductor carrying alternating current passes through metal
with magnetic properties, the inductive effect shall be minimized by (1) cutting slots in the metal
between the individual holes through which the individual conductors pass or (2)
passing all the conductors in the circuit through an insulating wall sufficiently
large for all the conductors of the circuit. Section 300.20 (B) Keep in mind, this is only able to be done with non-ferrous raceways.
Jeff H.28. I ran 3 sets of 500 KCMILL copper for the service conductors of a 1,200
Amp fused service disconnect and I was told that the wire is too small in
size, why is that?
380 for 1 conductor times 3 is 1140 which is less than 1,200 cannot round up
after 800 amps. Section 310.16 and 240.4
Dan S.29. Talking to others at the local supply house they were saying I can not
use 4/0 aluminum for a 200-amp service for a coffee house, is that true?
4/0 aluminum is listed at 180 amps at 75 degree C as long as the calculated load
is 180 amp or less then you can round up to the next common size overcurrent
which is 200 amp. Section 240.3 and 310.16
Larry K.30. I was written up for having a 100-amp breaker protecting a feeder of #2 AL
SER cable for a sub panel in a new addition for a dwelling unit. I thought
that #2 AL is good for 100 Amps
You are thinking of 310.12 for residential main service table where #2 AL is good for 100
Amps only if supplying total load of house. Otherwise, #2 AL at 75 degree C is 90
Amps. Section 310.12 and 310.16
Jeff L.31. Can you tell me where in the code it flat out says that you can only load a
circuit breaker 80% if the load on the circuit lasts longer than 3 hours?
That requirement is found in the UL white book. Unless otherwise marked, circuit
breakers should not be loaded to exceed 80% of their current rating, where in
normal operation the load will continue for three hours or more. Section UL White Book DIVQ
Doug B.32. Do you know where I can find the requirements of a metal box installed in
a firewall?
Certified single- and double-gang metallic outlet and switch boxes with metallic or
nonmetallic cover plates may be used in bearing and nonbearing wood stud and
steel stud walls with ratings not exceeding 2 h. Section UL White Book QCIT
Jeff H.33. I have the style of four-square boxes that have combination 3/4″ and 1/2″
KO’S if I only use the 1/2″ KO’S do I have to install a bond bushing on a 277/480-vold system?
All boxes with concentric or eccentric knockouts have been investigated for
bonding and are suitable for bonding without any additional bonding means
around concentric (or eccentric) knockouts were used in circuits above or below
250-volts and may be marked as such. Section UL White Book QCIT
Dan S.34. Is a plain old four-square box considered concrete tight?
Answer All metal boxes, except aluminum alloy boxes, are provided with corrosion
protection suitable for installation in concrete. Section UL White Book QCIT
Larry K.35. Are there any questions you would like to ask any of us?