SolarAPP+: Contractor Input Training

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May 2021

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SolarAPP Product Releases

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• For all product release related information please visit https://help.solar-app.org
• You can find many other useful articles in the general category
• This webpage also includes our SolarAPP Production Improvements & Bugs that document all the bugs we have identified and the schedule of resolving them.

*Please check back regularly to get information on product improvements

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SolarAPP+ Contractor Input Training �(All Jobs)

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SolarAPP+: Login

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URL: https://solarapp.nrel.gov/

Username: email

Password: password

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SolarAPP+

SolarAPP+: Are you Eligible?

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Are you Eligible?

To complete your first project you must provide the following to solarapp@nrel.gov.

• State license number and expiration date for participating local government (link to state licensing board is acceptable)
• City business license and expiration date for participating local government (pocket card required)

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If SolarAPP+ is not active in a local government in your service territory the system cannot be used to pull a permit in that community.

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SolarAPP+: Start a New Project

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Prepare Materials

Have the following materials ready for reference:

• Plans with exact model numbers of equipment that will be used.
• Specification Sheets (uploaded in portrait mode for proper upload and visibility of content)
• Internal Project related data/documents
• Payment method

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Click the [New Project] button to start.

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SolarAPP+: Project Dashboard

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Projects

• List of created projects
• Show: See approval docs and payment history
• Edit: Make changes to a submission
• Final Project: Lock the design to further edits
• Archive Project: Delete the project

SolarAPP+: Start a New Project

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Create the Project

• Title = Job Code or however you wish to title the project, note this title will show up on approval documents
• Project Type = select the project type from the dropdown most commonly: rooftop solar also known as PV NEC 2017
• AHJ = Jurisdiction
• Address = Paste or enter in Project Address and choose to validate from drop down.
• Note: If address is not validated, check to confirm the address is in the AHJ you selected.
• If it is in the AHJ selected, confirm the project is not new construction, or substantially close to being new construction (< 6 months since close of sale).

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SolarAPP+: Eligibility

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Scope of Work and Project Eligibility

• Scope of Work = Copy Scope of Work from PV-1.0
• Detail the following as needed:
• · PV kW DC system size (always required)
• · Main panel upgrade size (if applicable)
• · Main breaker derate (if applicable) and calculated residential load for the home on the main panel per NEC 220.83.
• City License Info = Select from the list
• State License Info = Select from the list
• Review the Eligibility checklist to ensure the submitted project qualifies for SolarAPP+
• Check the “All work shall comply…” checkbox, verifying compliance to NEC 2017 and 2018 IRC.

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SolarAPP+: Fire

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Fire Page

• Review the SolarAPP+ Fire Bulletin to ensure the submitted project qualifies for SolarAPP+
• In-dwelling automatic sprinklers = confirm in design documents, as this may be listed in notes of the plan.
• This influences whether there are 18 inch or 3 ft setbacks based on the array’s area and coverage of the roof.
• Roof Area = Confirm in design document, as this may be noted in an array details section as seen below.

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SolarAPP+: Structural

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1. Weight = must be lower than 4 lbs per sq foot and check design plans to confirm.
2. Will attachment spacing be stacked or staggered? See configuration.
3. On center attachment spacing, specify in inches.

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Structural Page

SolarAPP+: Structural - Roof Planes

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Structural Page

• Number of unique mounting planes, each roof will have its own section for the following info
• Flush mount or Tilt up racking = See detail
• See array info for roof type by array = Type
• Conditional based on roof covering type = Composite shingle and must be < 2
• Convert pitch from degrees to Rise-over-run
• Module height above the roof surface = See elevation detail

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SolarAPP+: Structural

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Structural Page Con’t

• Does the roof structure appear structurally sound…? = Yes
• Module and mounting designed to withstand expected loads? = Yes

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Any red flag structural issues will be called out by design at the customer huddle. Structural upgrades may be performed during installation. The answer to this question must be “YES” to be compatible with SolarAPP+.

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The Solar module and mounting system will be qualified by the manufacturer and supported through the racking system. The datasheet uploaded for the racking system will have the list of approved modules.

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SolarAPP+: Structural

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Structural Page Notes - Tilt Up System

For Tilt up systems, at least 20% of the module must have height less than 24 inches off the roof surface.

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The code allows the reduction of live load to zero in areas where the PV array is less than 24 inches from the roof surface.

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As long as at least 20% of the array area is less than 24” from the roof surface, we can calculate that the total dead + live load on the roof is equivalent before and after the addition of the PV to the roof, and therefore meets section 403/503 of the IEBC.

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As a result, the module to the right would qualify as eligible in SolarAPP+, even though some of the module’s height exceeds 24 inches.

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SolarAPP+ Contractor Input Training - Electrical (Microinverters)

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SolarAPP+: Electrical: Inverters

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Electrical Page

Micro inverters i.e. Enphase

• Upload datasheets the first time, and then for all future submissions you can select it from the drop-down

(if applicable), Select the appropriate model number.

• Manufacturer = Select from the dropdown list
• Select the inverter model number
• This question is accessing a database of approved equipment based on the manufacturer selection. Model numbers are required to match exactly.
• Architecture type = Microinverter
• Combiner panel = YES, per the design of the system.
• Busbar size of Combiner panel = 125, per the design

of system.

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SolarAPP+: Electrical: Modules

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Electrical Page

Modules

• Datasheet = pre-populate from drop down (after first submission), Select the appropriate model number.
• Manufacturer = Select from the dropdown list
• Select the inverter model number
• This question is accessing a database of approved equipment based on the manufacturer selection. Model numbers are required to match exactly.
• Module Quantity can be gleaned from the design, single line diagram or the scope of work.

SolarAPP+: Electrical: Racking/Flashing

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Electrical Page

Racking/Flashing

• Datasheet = pre-populate from drop down (after first submission) or upload, select the appropriate model number.
• Manufacturer = See detail on design data sheet for manufacturer name, SnapNRack, here.
• Model Number = See detail on design
• Combination of racking and modules listed to UL 2703 = Yes, per datasheet.
• Fire Classification = Yes, per datasheet.
• Flashing = See design details
• Datasheet = pre-populated (after first submission) or upload. Select the appropriate model number.
• Flashing installed per manufacturer instruction = Yes.

SolarAPP+: Racking/Flashing

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Electrical Page

Racking/Flashing

• To specify fire classification for the combination of racking system and modules to UL 2703 the contractor is required to upload the installation manual that clearly lists the approved modules that match the SolarAPP submission.
• For a SolarAPP project employing the RL Universal Racking system with Longi LR4-60HPH-360M modules, the contractor would upload a copy of the Racking system installation manual containing the specific model numbers for the installed module as shown here.
• Learn more on UL 2703 here.

SolarAPP+: Racking/Flashing (Continued)

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Electrical Page

Racking/Flashing

• The contractor could also collect this information directly from a NRTL and their product information page, which verifies the 2703 certification of the mounting system with a specific module for bonding, grounding, mechanical loading, and system fire classification.
• Here we show an example using GAF’s DecoTech RI 2000 mounting system and an example module: Solaria PowerXT-325R-BX / 330R-PX.
• Learn more on UL 2703 here.

SolarAPP+: Electrical: Rapid Shutdown

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Electrical Page

For microinverter like an Enphase systems = Yes

Rapid Shutdown: Know your tech!

1. RSD listed to UL 1741 = Yes. Find this info on the datasheet for Microinverters, AC Modules, or Optimizers

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SolarAPP+: Electrical: Installation Details

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Installation details is about the materials we use for install, except….

• Existing PV systems and energy storage NOT allowed
• Conductor type = Yes
• Rooftop Conduit height = Yes
• PV wire or Use-2 = Yes
• Pv wire diameter = Yes
• Terminal rating = Yes
• Grounding conductor = Yes
• Voltage and current spec within range of connected equipment? = Yes

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The Installation Details section sets the minimum requirements for installation materials that inform SolarAPP+ code compliance checks. The contractor MUST adhere to these requirements at installation in order to maintain SolarAPP+ eligibility. Diameter, height, and rating contribute to the calculations used for conductor size, conduit fill, and conductor ampacity derating.

Electrical Page

SolarAPP+: Electrical: Circuit Requirements

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Electrical Page

For Enphase example

1. Max number of AC CCC in raceway, a function of how many branch strings are on the roof x 2.
2. Max number of micros in a branch = Branch of (X)
3. One Micro per module = Yes
4. Max OCPD of 20A per Branch = Yes

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SolarAPP+: Electrical: Circuit Requirements

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Electrical Page

For Enphase, AC current carrying conductors (CCC) refers to the AC output conductors of microinverter branch circuits. The SolarAPP+ is using this value to calculate conduit and wire size.

• Each branch circuit will have (2) CCC. This value will increase with each subsequent branch circuit of microinverters. A system with 2 branches of microinverters will have (4) CCC.
• The output of the combiner box to the point of interconnection will have (3) CCC by default in SolarAPP+.
• For more information on this topic see the appended slides.

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AC Current Carrying Conductors

Branch Circuits >

Combiner box >

SolarAPP+ Contractor Input Training - Electrical (String w/DC)

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SolarAPP+: Electrical: String Inverters with DC-DC Converters

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Electrical Page

With DC-DC converters i.e. Solaredge SE7600H

• Datasheet = pre-populate from drop down (after first submission), Select the appropriate model number.
• Manufacturer = Select from the dropdown list
• Select the inverter model number
• This question is accessing a database of approved equipment based on the manufacturer selection. Model numbers are required to match exactly.
• Architecture type = String inverter with DC-DC converters
• Datasheet - pre-populate from drop down (after first submission, select the appropriate model number.
• 2nd Inverter = if yes, see scope of work and/or refer to electrical diagram. If so, provide details in similar fashion as first inverter.
• Inverter outputs must have the same point of interconnection method for eligibility in SolarAPP+.

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SolarAPP+: Electrical: Modules

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Electrical Page

Modules

• Datasheet = pre-populated from dropdown (after first submission), Select the appropriate model number.
• Manufacturer = Select from the dropdown list
• Select the inverter model number
• This question is accessing a database of approved equipment based on the manufacturer selection. Model numbers are required to match exactly.
• Module Quantity can be gleaned from the single line diagram and/or the scope of work.

SolarAPP+: Electrical: Racking/Flashing

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Electrical Page

Racking/Flashing

• Datasheet = pre-populate from drop down (after first submission), Select the appropriate model number.
• Manufacturer = see details on design data sheet for manufacturer name in this case SnapNRack
• Model Number = See detail on design and the related data sheet.
• Combination of racking and modules listed to UL 2703 = Yes
• Fire Classification = Yes
• Flashing = See detail on design and related data sheet.
• Datasheet = pre-populate from drop down (after first submission), Select the appropriate model number.
• Flashing installed per MFG instruction = Yes.

SolarAPP+: Racking/Flashing

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Electrical Page

Racking/Flashing

• To specify fire classification for the combination of racking system and modules to UL 2703 the contractor is required to upload the installation manual that clearly lists the approved modules that match the SolarAPP submission.
• For a SolarAPP project employing the RL Universal Racking system with Longi LR4-60HPH-360M modules, the contractor would upload a copy of the Racking system installation manual containing the specific model numbers for the installed module as shown here.
• Learn more on UL 2703 here.

SolarAPP+: Racking/Flashing (Continued)

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Electrical Page

Racking/Flashing

• The contractor could also collect this information directly from a NRTL and their product information page, which verifies the 2703 certification of the mounting system with a specific module for bonding, grounding, mechanical loading, and system fire classification.
• Here we show an example using GAF’s DecoTech RI 2000 mounting system and an example module: Solaria PowerXT-325R-BX / 330R-PX.
• Learn more on UL 2703 here.

SolarAPP+: Electrical: Rapid Shutdown for DC String Inverters

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For DC String inverter (i.e. Delta, Solaredge, or SMA) = Yes

Electrical Page

Rapid Shutdown: Know your tech!

• RSD listed to UL 1741 = Yes. Find this info on the datasheet for Optimizers or DCDC converters..

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SolarAPP+: Electrical: Installation Details

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Installation details is about the materials we use for install, except….

• Existing PV systems and energy storage NOT allowed
• Conductor type = Yes
• Rooftop Conduit height = Yes
• PV wire or Use-2 = Yes
• Pv wire diameter = Yes
• Terminal rating = Yes
• Grounding conductor = Yes
• Voltage and current spec within range of connected equipment? = Yes

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The Installation Details section sets the minimum requirements for installation materials that inform SolarAPP+ code compliance checks. The contractor MUST adhere to these requirements at installation in order to maintain SolarAPP+ eligibility. Diameter, height, and rating contribute to the calculations used for conductor size, conduit fill, and conductor ampacity derating.

Electrical Page

SolarAPP+: Electrical: DC-String Inverters Circuit Requirements

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For “With DC-DC converters” (aka Solaredge)

• Max number of DC Current carrying conductor (CCC) PV wire in raceway = enter 2 per the number of circuits from roof to ground in the same raceway, one 10AWG THWN-2 EGC is used for conduit fill calculations. See conduit schedule.
• Max number of DC CCC THWN wire in raceway = Enter 0 for PV wire used from array to inverter directly or (2) per the number of circuits from roof to ground in a single raceway. See conduit schedule.
• Are any series strings combined in parallel? Enter “No” or “Yes” depending if you choose to combine strings in parallel on the roof to reduce the amount of wires in the raceway.
• Max number of modules in a branch = Branch of (X)
• Is string voltage less than 600V = Must be specified on datasheet or not eligible for SolarAPP+.

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Electrical Page

SolarAPP+: Electrical: DC-String Inverters Circuit Requirements

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Electrical Page

DC Current Carrying Conductors

AC

DC

DC

AC

DC current carrying conductors (CCC) refers to the DC source circuit conductors from the array to the inverter. Each branch circuit will have (2) CCC. The SolarAPP+ is using this value to calculate conduit and DC wire size. This value will increase with each subsequent branch circuit of modules. A circuit with 2 branches of modules will have (4) CCC. AC CCC refers to the inverter output circuits and per the example, each inverter has (3) CCC in a single raceway. The output of the PV load center is always assumed to have (3) CCC.

• For more information on this topic see the appended slides.

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SolarAPP+: Electrical: DC-String Inverters Circuit Requirements

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For “With DC-DC converters” (aka Solaredge)

• How many series strings are combined in parallel?
• When no strings combined in parallel enter 1.
• When combining two series strings in parallel, enter 2.
• An electrical parallel connection must consist of no more than 2 strings.
• Note: ok to have multiple parallel connected strings so long as each connection consist of no more than 2 strings. See examples below.
• See conduit schedule.

Series Strings in Parallel

SolarAPP+ Contractor Input Training - Electrical (String w/o DC)

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SolarAPP+: Electrical: String Inverters w/o DC-DC Converters

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Electrical Page

Without DC-DC converters i.e. Delta M, Solaredge HD wave

• Datasheet = upload or pre-populate from drop down (after first submission), Select the appropriate model number.
• Manufacturer = Select from the dropdown list
• Select the inverter model number
• This question is accessing a database of approved equipment based on the manufacturer selection. Model numbers are required to match exactly.
• Architecture type = String inverter without DC-DC converters
• 2nd inverter = See scope of work and/or refer to electrical diagram. If yes, provide similar information to that of inverter 1, in addition add the busbar size of PV combiner panel based on details of design.
• Datasheet, upload or pre-populate from drop down (after first submission).
• Manufacturer
• Model
• All inverter outputs must have the same point of interconnection = Yes
• Combiner panel = YES if 2nd inverter AND PV Combiner panel on plans
• Busbar size of Combiner panel = See detail on design, diagram, or plan.

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SolarAPP+: Electrical: Modules

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Electrical Page

Modules

• Datasheet = pre-populate from drop down (after first submission) or upload, Select the appropriate model number.
• Manufacturer = Select from the dropdown list
• Select the inverter model number
• This question is accessing a database of approved equipment based on the manufacturer selection. Model numbers are required to match exactly.
• Module Quantity can be gleaned from the single line diagram or the scope of work.

SolarAPP+: Electrical: Racking/Flashing

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Electrical Page

Racking/Flashing

• Datasheet = pre-populate from drop down (after first submission) or upload, Select the appropriate model number.
• Manufacturer = see detail on design or SnapNRack here.
• Model Number = See detail on design data sheet for exact model.
• Combination of racking and modules listed to UL 2703 = Yes, confirm via datasheet.
• Fire Classification = Yes
• Flashing = See detail on design data sheet
• Datasheet = pre-populate from drop down (after first submission) or upload, Select the appropriate model number.
• Flashing installed per MFG instruction = Yes.

SolarAPP+: Racking/Flashing

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Electrical Page

Racking/Flashing

• To specify fire classification for the combination of racking system and modules to UL 2703 the contractor is required to upload the installation manual that clearly lists the approved modules that match the SolarAPP submission.
• For a SolarAPP project employing the RL Universal Racking system with Longi LR4-60HPH-360M modules, the contractor would upload a copy of the Racking system installation manual containing the specific model numbers for the installed module as shown here.
• Learn more on UL 2703 here.

SolarAPP+: Racking/Flashing (Continued)

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Electrical Page

Racking/Flashing

• The contractor could also collect this information directly from a NRTL and their product information page, which verifies the 2703 certification of the mounting system with a specific module for bonding, grounding, mechanical loading, and system fire classification.
• Here we show an example using GAF’s DecoTech RI 2000 mounting system and an example module: Solaria PowerXT-325R-BX / 330R-PX.
• Learn more on UL 2703 here.

SolarAPP+: Electrical: Rapid Shutdown for w/o DC String Inverters

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Rapid Shutdown: Know your tech!

• RSD listed to UL 1741 = Yes. Find this info on the datasheet for DC-DC converters rapid shut down (RSD)/middle circuit interrupter (MCI)
• Outside array boundary RSD listed to UL 1741 = Yes. Find this info on the datasheet for module-level power electronics (MLPE)
• Manufacturer = See detail on design and data sheet such as APS
• Model Number = OPT-XXX or RSD-S-PLC
• Datasheet for outside the array boundary. For these systems, RSD devices perform BOTH the outside and inside the array boundary functions. Upload or select the appropriate datasheet based on manufacturer and model number.
• Method of compliance = select 690.12(b)(2)(1) OR Controlled conductors per 690.12(B)(2)(2) where applicable.
• Datasheet for RSD device = Upload or select the same datasheet as above based on MFG and model number.
• Manufacturer = See details on design data sheet such as Delta
• Model Number = See details on design data sheet such as OPT-300 or RSD-S-PLC
• Inside array boundary RSD listed to UL 1741 = Yes. Find this info on the datasheet for DC-DC converters (Optimizers) or module-level power electronics (MLPE)

For DC String inverter (i.e. Delta, Fronius, or SMA) = Yes

Electrical Page

SolarAPP+: Electrical: Installation Details

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Installation details is about the materials we use for install, except….

• Existing PV systems and energy storage NOT allowed
• Conductor type = Yes
• Rooftop Conduit height = Yes
• PV wire or Use-2 = Yes
• Pv wire diameter = Yes
• Terminal rating = Yes
• Grounding conductor = Yes
• Voltage and current spec within range of connected equipment? = Yes

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The Installation Details section sets the minimum requirements for installation materials that inform SolarAPP+ code compliance checks. The contractor MUST adhere to these requirements at installation in order to maintain SolarAPP+ eligibility. Diameter, height, and rating contribute to the calculations used for conductor size, conduit fill, and conductor ampacity derating.

Electrical Page

SolarAPP+: Electrical: DC-String Inverters Circuit Requirements

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Electrical Page

DC Current Carrying Conductors

AC

DC

DC

AC

DC current carrying conductors (CCC) refers to the DC source circuit conductors from the array to the inverter. Each branch circuit will have (2) CCC. The SolarAPP+ is using this value to calculate conduit and DC wire size. This value will increase with each subsequent branch circuit of modules. A circuit with 2 branches of modules will have (4) CCC. AC CCC refers to the inverter output circuits and per the example, each inverter has (3) CCC in a single raceway. The output of the PV load center is always assumed to have (3) CCC.

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SolarAPP+: Electrical: DC String Inverters w/o DC-DC

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Electrical Page

For “Without DC-DC converters” (aka Delta E/M)

• Max number of DC Current carrying conductors (CCC) PV wire in raceway = enter 2 per the number of circuits, from roof to ground, in the same raceway, one 10AWG THWN-2 EGC is used for conduit fill calculations. See conduit schedule.
• Max number of DC CCC THWN wire in raceway = Enter 0 for PV wire used from array to inverter directly or (2) per number of circuits from roof to ground contained in a single raceway. See conduit schedule.
• Are any series strings combined in parallel? Enter “No” or “Yes” depending if you choose to combine strings in parallel on the roof to reduce the amount of wires in the raceway
• Max number of modules in a branch = String of (X) modules.

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SolarAPP+: Electrical: DC-String Inverters Circuit Requirements

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• How many series strings are combined in parallel?
• When no strings combined in parallel enter 1.
• When combining two series strings in parallel, enter 2.
• An electrical parallel connection must consist of no more than 2 strings.
• Note: ok to have multiple parallel connected strings so long as each connection consist of no more than 2 strings. See examples below.
• See conduit schedule.

Series Strings in Parallel

SolarAPP+: Electrical: Inverter Output AC

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Electrical Page

For all architectures

• Max number of AC CCC THWN wire in raceway = (3) per inverter in a single raceway. The output of the combiner panel is default to (3)
• Will NM cable be used? = No (See conduit schedule)
• Except: Microinverter Array conductors using NM cable in the attic for new construction =Yes

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SolarAPP+ Contractor Input Training - Electrical (AC Modules)

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SolarAPP+: Electrical: AC Modules (Inverter Section)

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Electrical Page

AC Module (Inverter section)

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1. Datasheet > Upload AC module datasheet
2. Manufacturer > Select AC module manufacturer from the dropdown
3. Select the AC module model number
1. Model numbers are required to match CEC listing exactly.
4. Architecture type > AC Module
5. Same point of connection > Select Yes if all AC module branch circuits share same point of connection
6. Combiner panel > Select Yes if AC module branch circuits are being combined.
7. Busbar size of Combiner panel > Enter busbar size of PV combiner panel

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SolarAPP+: Electrical: AC Modules (Module Section)

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Electrical Page

AC Module (Module section)

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• Datasheet > Upload AC Module datasheet
• Manufacturer > Search manufacturer in field and select AC Module manufacturer from dropdown
• Select DC Module model number as AC module model number.
• To find the DC variant of AC module, CEC list has DC module model number listed in the AC module listing, then search DC module model number in SolarAPP+ input field and select matching DC module model number.

*For SunPower module (select SunPower as manufacturer, not Sunpower)

• Enter quantity of module based on system design.

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SolarAPP+: Electrical: AC Modules (Racking/Flashing)

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Electrical Page

Racking/Flashing

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• Datasheet > Upload racking system datasheet
• Manufacturer > Enter racking manufacturer
• Model Number > Enter racking system module number matching design and datasheet uploaded
• Confirm racking and modules combination is UL 2703 listed > Select Yes
• Confirm racking and modules combination fire classification with roofing type > Select Yes
• Flashing > Enter flashing matching design
• Datasheet > Upload flashing datasheet
• Must agree to install flashing per MFG instruction > Select Yes

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SolarAPP+: Racking/Flashing

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Electrical Page

Racking/Flashing

• To specify fire classification for the combination of racking system and modules to UL 2703 the contractor is required to upload the installation manual that clearly lists the approved modules that match the SolarAPP submission.
• For a SolarAPP project employing the RL Universal Racking system with Longi LR4-60HPH-360M modules, the contractor would upload a copy of the Racking system installation manual containing the specific model numbers for the installed module as shown here.
• Learn more on UL 2703 here.

SolarAPP+: Racking/Flashing (Continued)

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Electrical Page

Racking/Flashing

• The contractor could also collect this information directly from a NRTL and their product information page, which verifies the 2703 certification of the mounting system with a specific module for bonding, grounding, mechanical loading, and system fire classification.
• Here we show an example using GAF’s DecoTech RI 2000 mounting system and an example module: Solaria PowerXT-325R-BX / 330R-PX.

SolarAPP+: Electrical: AC Modules (Rapid Shutdown)

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Rapid Shutdown:

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• Confirm selected AC Module is UL1741 listed on datasheet > Select Yes if UL 1741 listed.

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Electrical Page

SolarAPP+: Electrical: AC Modules (Install Details)

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The Installation Details section sets the minimum requirements for installation materials that inform SolarAPP+ code compliance checks. The contractor MUST adhere to these requirements at installation in order to maintain SolarAPP+ eligibility. Diameter, height, and rating contribute to the calculations used for conductor size, conduit fill, and conductor ampacity derating.

Installation Details:

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• Existing PV system and/or energy storage is currently NOT allowed by SolarAPP+
• Confirm conductor types are allowed for PV system > Select Yes
• Confirm rooftop conduit will have minimum ¾” from roof surface > Select Yes
• PV wire or USE-2 > Select Yes
• PV wire diameter > Select Yes
• Terminal rating > Select Yes
• Confirm exposed equipment grounding conductor (EGC) to be minimum 6 AWG or protected > Select Yes

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Electrical Page

SolarAPP+: Electrical: AC Modules (Circuit Requirements)

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Circuit Requirements:

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• Enter maximum number of AC current carrying conductor in single raceway.
• Enter maximum number of AC module from the longest single branch.
• Confirm AC module branch circuit over-current protection device (OCPD):
• If branch circuit will be protected by 20A OCPD regardless of AC module branch length > Select Yes
• If branch circuit will be sized according to actual output current and protected by OCPD < 20A > Select No
• Confirm AC Module single branch circuit continuous output is < 16.5A > Select Yes
• Confirm if NM cable will be used for AC module output:
• Select No if wire types other than NM cable will be used
• Select Yes if NM cable will be used and installed according to applicable NEC code sections.

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Electrical Page

SolarAPP+: Electrical: AC Modules (Current Carrying Conductors)

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Electrical Page

SolarAPP+ Contractor Input Training (All Jobs continued)

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SolarAPP+: Electrical: Inverter Output AC

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Electrical Page

For all architectures

• Max number of AC CCC THWN wire in raceway = (3) per inverter in a single raceway. The output of the combiner panel is default to (3)
• Will NM cable be used? = No (See conduit schedule)
• Except: Microinverter Array conductors using NM cable in the attic for new construction =Yes

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SolarAPP+: Electrical: Relocated Loads = No

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Electrical Page

For all architectures

• Sometimes, interconnection at a panelboard requires that certain circuit breakers be relocated to a new sub-panel to allow space to land the PV overcurrent protective device. See the electrical circuit diagram for new (N) sub-panels and their ratings.

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SolarAPP: Electrical: Relocated Loads = Yes

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Electrical Page

For all architectures

1. When relocating loads from the main panel to a NEW sub panel to make room for the point of interconnection, = See SLD for details
2. Properly sized OCPD = YES
3. Busbar Ampere rating = See system design
4. Relocated loads Overcurrent protective device ampere rating = See system design
5. Is the subpanel located adjacent to the panelboard? = See site plan detail
6. Current Carrying Conductors includes relocated branch circuits AND Sub panel feeder conductors IF in a single raceway = See system design
7. Relocated branch circuits do not require ampacity derates if installed less than 2ft from panelboard. = See Site plan detail

​

SolarAPP: Electrical: Relocated Loads = Yes

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Electrical Page

For all architectures

1. When Branch Circuit conductors for relocated loads are relocated greater than 2ft = See site plan (typically = NO)
2. Are relocated branch circuit conductors extended less than 10ft or 10% of total circuit length = See Site plan (typically = YES)
3. Current Carrying Conductors includes relocated branch circuit conductors AND Sub panel feeder conductors IF in a single raceway = See system design
4. Are branch circuit conductors for relocated loads extended more than 6ft = See Site plan
5. Will the raceway size for Sub Panel feeders be sized according to the code = Yes
6. Will the raceway size for relocated branch circuit conductors be sized according to the code = Yes

​

SolarAPP: Electrical: Relocated Loads = Yes (con’t)

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Electrical Page

For all architectures

• When Branch Circuit conductors are relocated greater than 2ft = NO
• Are branch circuit conductors less than = YES
• Busbar Ampere rating = See system design
• Sub Panel feeder breaker ampere rating = See system design
• Is the subpanel located adjacent to the panelboard? = See site plan detail
• Current Carrying Conductors includes relocated branch circuits AND Sub panel feeder conductors IF in a single raceway = See system design
• Relocated branch circuits do not require ampacity derates if installed less than 2ft from panelboard. = See Site plan detail

​

SolarAPP+: Electrical: Point of Connection at Main Panel

Load Side 120% Rule

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Electrical Page

For all architectures

• A loadside interconnection using the 120% rule is the most common method of installation for PV only projects. It relies on the maximum inverter output, main breaker and main bus ratings to determine code compliance.
• The method of interconnection will be a listed circuit breaker

​

For example...

1. POI method at MSP = 705.12(B)(2)(3)(b) 120% rule or 705.12(B)(2)(3)(d) 120% rule on center-fed panels based on MSP
2. Main bus rating = see SLD
3. Main Breaker rating = See SLD
4. Utility service feed rated for = See Main Breaker/Main bus rating
5. Will inverter outputs be connected directly to a sub-panel = No for Meter socket adapter, check the SLD

​

SolarAPP+: Electrical: Point of Connection at Main Panel

Supply Side

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Electrical Page

For all architectures

• A supply-side interconnection is when the point of interconnection (POI) is ahead of the service disconnect (aka Main breaker). This can be accomplished through the use of an insulation-piercing connector, multi-port connector, breaker connector, meter lug connector, meter socket adapter, field evaluated supply-side connection, breaker connection at a main lug only (MLO) panel (aka “hot bus”), or a “solar-ready” panel slot.
• Each of these methods will have a specific “allowable backfeed” that SolarAPP+ will evaluate based on the answer to certain questions.

​

For meter socket adapter example...

• POI method at MSP = 705.12(A) Supply-side
• Main bus rating = see SLD
• Main Breaker rating = See SLD
• Utility service feed rated for = See Main Breaker/Main bus rating
• Service Equipment used = Meter Socket Adapter as an example
• Enter the AMP rating of the equipment = As an example 60A
• Datasheet
• Ampacity of the conductors fed by the SST = Same as utility service rating
• Supply-side conductor length less than 10ft = Yes
• Is the equipment used UL listed = Yes
• Will inverter outputs be connected directly to a sub-panel = No for Meter socket adapter, check the SLD

​

SolarAPP+: Electrical: Point of Connection at Main Panel

Load Side Sum of Breakers Rule

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Electrical Page

For all architectures

• A loadside interconnection using the Sum of Breakers rule is the most common method of installation for PV + Storage projects. It weighs the sum of breaker ratings on the bus plus the rating of the OCPD against the rating of the main bus. Design may relocate loads to a new subpanel to make this condition true.
• The method of interconnection will be a listed circuit breaker
• The sum of breakers will be validated at inspection by the AHJ.

​

For example...

• POI method at MSP = 705.12(B)(2)(3)(c) Sum of Breakers rule
• Main bus rating = see SLD
• Main Breaker rating = See SLD
• Utility service feed rated for = See Main Breaker/Main bus rating
• Will inverter outputs be connected directly to a sub-panel = Check the SLD for a sub-panel interconnection

​

SolarAPP+: Electrical: Point of Connection at Sub-Panel

​

67

Electrical Page

For all architectures

• A loadside interconnection may occur at a sub-panel. Specific compliance methods can be chosen at both the sub-panel and main panel boards.
• The method of interconnection will be a listed circuit breaker
• The sum of breakers will be validated at inspection by the AHJ.
• Interconnection rules must be maintained for all panelboards and conductors that carry the system backfeed to the utility grid.

​

For example, when applicable...

• Interconnection at sub-panel = Yes
• Main bus rating = see SLD
• Main Breaker rating = See SLD
• POI method at MSP = 705.12(B)(2)(3)(c) Sum of Breakers rule

Workers’ Comp

68

Workers’ Comp

• Agree to the terms and conditions and submit the project.

Standard Certifications

Review your Project Details

69

• Review Inspection checklist and Permit Long form for accuracy
• Go to payment.

Review Your Project Details

SolarAPP+ Fee Payment

70

• Enter card information and submit payment.
• If permit approval is also required via AHJ website, SolarAPP+ will prompt and provide direct link to AHJ permit submittal page.
• Complete permit application through AHJ website and upload SolarAPP+ approval documents and uploads (per instructions from AHJ).

Review Your Project Details

Making revisions in SolarAPP+

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​

​

71

Revising a Submitted Project in SolarAPP+

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• When you need to revise a project, you can select the edit button.
• The first 3 revisions in SolarAPP+ are free, but you may need to pay an AHJ revision fee for each revision you submit to the AHJ.

Edit in SolarAPP+

Revising a Submitted Project

73

• A revision in SolarAPP+ is only complete after you submit the revision and get a new approval ID.
• That revision will end with a new letter -B, or -C, or -D depending on the revision.
• In most cases, you will need to take the new approval documents and upload them as a revision within the AHJ’s permitting system. These revision processes vary by community.
• If you have questions about how to submit a revision in a SolarAPP+ community, reach out to SolarAPP@nrel.gov or the AHJ directly.
• Failure to submit a revision to the AHJ, will result in a failed inspection.

Submitting your Project to the AHJ

Example Revision Process:

Pima County/Tucson, AZ

74

1. Note: this is an example of a revision process in two communities, Pima County and Tucson Arizona. These processes vary by community.

​

• To revise your permit with Pima County/Tucson, please follow the steps below:
• Complete your revision with SolarAPP and download the relevant approval documents and approval ID.
• Compose an Email to BuildingPermit@Pima.gov
• Include in the Email Subject your permit number and the words SolarAPP+ Revision.
• In the body of the Email provide a detailed description for the revision and work affected.
• Attach your SolarAPP+ documents to the Email and send.
• Please allow 1-2 business days after submitting your revision for processing before scheduling your inspection.

Example Revision Process

End - SolarAPP+ Contractor Input Training

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SolarAPP+ Contractor Input Training: Appendix of Input Examples relating to CCCs

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Current Carrying Conductors (CCC) Overview: Microinverters

​

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1. The adjacent table includes the input for the number of AC current carrying conductors and DC current carrying conductors based on the inverter brand manufacturer and the expected system design.
2. It is possible that your system would not follow these expected designs. If so, be prepared to defend the selection with the SolarAPP+ team and likely the inspector out in the field.

All Inverters

Current Carrying Conductors (CCC) Overview: Microinverters

​

78

For Enphase, AC current carrying conductors (CCC) refers to the AC output conductors of microinverter branch circuits.  The SolarAPP+ is using this value to calculate conduit and wire size. 

• Each branch circuit will have (2) CCC.    This value will increase with each subsequent branch circuit of microinverters.  A system with 2 branches of microinverters will have (4) CCC. 
• The output of the combiner box to the point of interconnection will have (3) CCC by default in SolarAPP+.

See the following examples of Enphase microinverters and related CCCs.

Microinverters

Current Carrying Conductors (CCC) Overview: Microinverters

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Microinverters: Example 1

Wire call outs and respective CCC

1= 2 CCC

2= 2 CCC

3= 3 CCC

EGC not a CCC

​

Current Carrying Conductors (CCC) Overview: Microinverters

​

80

Microinverters: Example 2

Wire call outs and respective CCC

1= 2 CCC

2= 6 CCC

3= 3 CCC

EGC not a CCC

​

Current Carrying Conductors (CCC) Overview: Microinverters

​

81

Microinverters: Inputs

Max number of AC CCC in raceway, a

function of how many branch strings

are on the roof x 2

Max number of micro/AC modules

in a branch = Branch of (x)

(largest series branch)

Current Carrying Conductors (CCC) Overview: Microinverters

​

82

For Solaredge, DC current carrying conductors (CCC) refers to the DC output conductors of series string.  

• Each series string will have (2) CCC. 
• A system with parallel strings (2 series strings combined in parallel) will have (2) CCC. 
• If using a junction box or equivalent: transition from PV wire to THWN
• The output of the AC combiner box to the point of interconnection will have (3) CCC by default in SolarAPP+.

​

String Inverter w/DC

Current Carrying Conductors (CCC) Overview: String Inverter w/DC

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83

String Inverter w/DC: Example 2

Wire call outs and respective CCC

1= 2 CCC

2= 2 CCC

3= 4 CCC

4= 3 CCC

EGC not a CCC

​

Current Carrying Conductors (CCC) Overview: String Inverter w/DC

​

84

String Inverter w/DC: Example 3

Wire call outs and respective CCC

1= 4 CCC

2= 2 CCC

3= 2 CCC

4= 4 CCC

5= 3 CCC

EGC not a CCC

​

Current Carrying Conductors (CCC) Overview: String Inverter w/DC

​

85

String Inverter w/DC: Example 4

Wire call outs and respective CCC

1= 2 CCC

2= 3 CCC

3= 2 CCC

4= 3 CCC

5= SolarAPP+ will automatically default to 3 CCC

EGC not a CCC

​

Current Carrying Conductors (CCC) Overview: String Inverter w/DC

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86

String Inverter w/DC: Example 5

Wire call outs and respective CCC

1= 2 CCC

2= 2 CCC

3= 4 CCC

4= 3 CCC

At junction box PV wire transitions to THWN

EGC not a CCC

​

Current Carrying Conductors (CCC) Overview: String Inverter w/DC

​

87

String Inverter w/DC: Example 6

There are (0) PV wire in raceway, (4) THWN-2 DC conductor in raceway, and (3) THWN-2 AC conductor in raceway.

Current Carrying Conductors (CCC) Overview: Microinverters

​

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String Inverters w/DC-DC Converters: Inputs

Max number of DC CCC in raceway

PV wire

Max number of DC CCC in raceway

THWN wire

If 2 series strings combined

in parallel = Yes

Max number in a series string = Branch of (x)

(largest series string)