City of Moab (UT)

Codes

NEC Code Version

2017

Fire Code Version

2018 Building Code

Code List

2021 INTERNATIONAL BUILDING CODE 2021 INTERNATIONAL RESIDENTIAL CODE 2021 INTERNATIONAL MECHANICAL CODE 2021 INTERNATIONAL PLUMBING CODE 2021 INTERNATIONAL FUEL GAS CODE 2021 INTERNATIONAL ENERGY CONSERVATION CODE 2021 INTERNATIONAL EXISTING BUILDING CODE 2021 INTERNATIONAL SWIMMING POOL AND SPA CODE 2020 NATIONAL ELECTRICAL CODE

ASCE Code Specification

ASCE 7-16

SolarAPP+ & submittal

Revision Required

0

New Planset Required For Module Swap

0

Fire setbacks

Fire Setback Enforced

1

Setback Notes

Standard

Structural & loads

Wind Speed

90

Snow Load

999

Reducible Snow Load Allowed

1

Max Attachment Spacing

96

Minimum Ground On Roof

#10

Electrical

Electrical Load Calcs Required

Derates

Allowed POI

Line Side Taps,PV Breaker,Meter Adapter,Load Side Taps

Panel Schedule Required

Partial Home Backup

Temperature Rating

90

De Rating Ampacity

0.91

Battery / ESS

Unique Battery Placards Needed

0

ESS Notes

Standard

Separate ESS Disconnect Required

ESS Disconnect

ESS Elevation Detail Required

No

Plan set

Site

A. Site plan must show the location of the home’s service panelboard, any sub-panelboard (that is to be backfed by the PV system), location(s) of the inverter(s), locations of any disconnects, and layout of the solar PV modules (panels). B. Show any detached structure on the property if solar modules (panels) are to be installed thereon and show dimensions from such structure to property lines. C. Show on the site plan where the “rapid shutdown” disconnect (for the “rapid shutdown” of the PV system, as required per NEC 690.12) will be located. Note: The location of the “rapid shutdown” disconnect is not specifically noted in the code and its required location could vary per AHJ.

Roof Plan

A. Specify the type of roof covering and note how many layers of such covering. B. Indicate what type of rafters the roof is composed of (engineered trusses, dimensional lumber, TJI, etc.) and note the size, spans, and spacing of the rafters. C. Show that the existing roof rafters can safely handle the new loads of the system. Note: Engineering to meet this requirement may not be required if the existing rafters are engineered trusses, the roof has only one layer of asphalt shingles, and the total weight of all racking system with PV modules (panels) installed does not exceed 5 psf and there is not more than 60 lbs per solar racking support (subject to Building Official’s approval). D. Provide manufacture information that shows the mounting system is listed for the mounting of PV modules on the roof (for roof mounted systems). E. Specify on the plans the spacing of supports per the manufacture’s specifications and show that such system can handle the local wind and snow loads and is designed for such. Grand County/City of Moab’s maximum wind load is to be based on 115 mph, ground snow load is to be based on 36 psf below 500 ft or 65 psf 5000 ft and above, and roof snow load is to be based on 25 psf below 5000 ft and 45 psf 5000 ft and above. F. Provide information on how all roof penetrations (supports, J-boxes, conduit, etc.) are going to be properly flashed. IRC M2302.2.2 G. Specify on the plans that solar PV modules (panels) cannot be installed over or block any attic vents, plumbing vents, furnace or water heater vents, etc. H. For a ground-mount racking system, provide complete plans of the structure indicating that all associated requirements of the code are met (setbacks, square footage of the racking footprint, size/spacing of footings, connectors, snow loads, wind loads, etc.). IRC R324.6

Roof Plan Notes

PV modules (panels) cannot be installed over or block any attic vents, plumbing vents, furnace or water heater vents, etc.

Electrical Diagram

A. Specify exactly how many solar PV modules (panels) per AC circuit will be installed (the number of micro inverters per circuit cannot exceed what is noted on the inverter spec sheets) or per string (DC source circuit) will be installed. B. Specify how many AC circuits or strings (DC source circuits) are to be installed for the PV system. C. Show all PV system components, such as: J-boxes, combiner box (if used), micro-inverters, panelboards, disconnects and other equipment like charge controllers and batteries (if used). Indicate where all the components will be located in or on the home. D. Indicate the electrical panelboard that the PV system will tie into: A sub-panelboard or the home’s electrical service panelboard. E. Specify on the diagram the ratings of all breakers or fuses (AC overcurrent protection devices or DC and AC overcurrent protection devices) including existing breakers feeding any panels that are to be backfed by the PV system. F. Show all wire sizes and wire types including any existing feeder wires that are to be backfed by the PV system. G. Trunk cables located outdoors for a micro inverter system are required to be either TC-ER or USE-2 cable and must be secured no more than 6' oc. NEC 690.31(D) H. The wiring system used at the array must be the approved wiring system required per the micro inverter manufacture. I. Wires installed outside (even if in conduit) must be listed for wet locations. NEC 300.9 J. If exposed outside, wires must be type USE-2 or listed “PV” conductors. NEC 690.31(B). All wires are strongly recommended to be rated 90°C (i.e., RHW-2, THWN-2, and XHHW-2) due to deration issues. K. For transformerless inverters, all DC wiring at the array must be the “PV wire” type and be listed as such. Specify this on the plans. NEC 690.35(D). Note: MC cable is permitted for DC wiring in the home or building. NEC 690.31(G) L. Specify the size and type of all equipment grounding conductors and grounding electrode conductors. Note: Transformerless micro-inverters often do not require a grounding electrode conductor, but all types of PV systems will require equipment grounding conductors or DC and AC equipment grounding conductors. NEC 690.43-690.47 M. The AC circuit conductors (wires) must be at least #12 AWG copper (#10 AWG is recommended). String (DC source circuit) conductors (wires) must be at least #12 AWG copper (#10 AWG is recommended). Note: Wires may need to be increased in sized due to conduit fill or ampacity derations per NEC Tables 310.15(B)(3)(a), 310.15(B)(3)(c), and 310.15(B)(2)(a), where applicable. N. The rating of the fuses or breaker for the micro-inverter’s AC output circuit must be sized in accordance with the micro-inverter’s manufacture spec sheets. O. Show conduit types, sizes, and how many conductors will be in each conduit. P. Specify locations where conduit and/or cables are to be installed. Q. If more than two strings (DC source circuits) are to be combined together, specify 15 amp DC fuses for each ungrounded wire (usually the positive DC wires) at the DC combiner. NEC 690.9. For transformerless inverters, specify a fuse for both the positive and negative conductors for each string when combining three or more strings. NEC 690.35(B) R. If a detached DC combiner panel is to be installed, specify the size of wires between the DC combiner and the inverter (this is called the “PV output circuit” per the NEC). These wires are sized by multiplying the solar PV module (panel) short circuit current (Isc) rating by 1.56 and then multiplying by the number of DC strings being combined. Example: Solar module Isc of 9 amps, 9 × 1.56 = 14.04 amps, and if there are three strings being combined together then the PV output circuit wires must be sized per 42.12 amps. NEC 690.8(A)(1&2) and 690.8(B)(2) S. Note that any DC circuits that penetrate and enter the home will be ran in metal conduit or be MC cable. NEC 690.31(E) T. The wires and breaker for the inverter’s AC output circuit must be sized by taking the inverter’s AC output current (amps from inverter spec sheet) and increase by 1.25 (125%). Example: If inverter AC output amps is 22A, 22 × 1.25 = 27.5A. Thus the wires in this example are sized per 27.5A and connect to a 30 amp AC breaker. NEC 690.8(A)(3) and 690.8(B)(1&2)

Label Page

A. Provide manufacture’s specifications for the solar PV modules (panels). B. Manufacture’s specifications must show the PV modules are UL 1703 listed. NEC 690.4(D) C. Solar PV Module specification sheets must show the STC rated open circuit voltage (Voc) and short circuit current (Isc) of the modules (panels). D. The maximum DC voltage (Voc) at the coldest outside temperature cannot exceed 600V DC (for residential). To find the max DC voltage, add the Voc from each module on a single string and increase such voltage by 16% to 20% (depending on the module spec sheets). Note: 20% increase is considered very conservative (for areas where temperature can be as low as -13˚F) but module spec sheets can be used to obtain a more accurate calculation when needed. NEC 690.7

Ground mount

Ground Mount Fencing Required

Mesh/Scrim