Specialty Engineering

Specialized deliverables for complex requirements.

Three-line diagrams, single-line diagrams, PE stamping, interconnection applications, commissioning plans, and technical research — handled by specialists.

Starting at$149per deliverable
Turnaround1 – 4 daysavg. delivery
Free trialYOUR FIRST DELIVERABLE IS ON USCreate an account to claim
[Specialty Engineering Dashboard Screenshot]

Every Deliverable, Detailed

Electrical Diagrams

Single-Line Diagram (SLD)

Complete single-line diagram showing the electrical system from PV array through point of interconnection. PE-stamped and utility-ready.

What's included
  • Full system single-line diagram
  • Equipment ratings and specifications
  • Protection device coordination
  • PE stamp and certification
[Single-Line Diagram (SLD) Sample]

Three-Line Diagram (3LD)

Detailed three-line diagram showing all three phases of the electrical system. Required for larger commercial and utility-scale installations.

What's included
  • Three-phase system detail
  • Conductor sizing and routing
  • Overcurrent protection details
  • Grounding and bonding details
[Three-Line Diagram (3LD) Sample]
Stamping & Certification

Electrical Stamping

PE review and stamp for electrical designs. Our licensed engineers review your plans and provide certification for AHJ submission.

What's included
  • Licensed PE review
  • Code compliance verification
  • Wet stamp or digital stamp
  • Certification letter
[Electrical Stamping Sample]

Structural Stamping

PE review and stamp for structural designs. Covers roof loading, racking attachments, and foundation designs.

What's included
  • Structural load analysis review
  • Attachment detail verification
  • Foundation design review
  • PE stamp and certification
[Structural Stamping Sample]
Applications & Plans

Interconnection Application

Complete utility interconnection application package with all required technical documentation, diagrams, and forms.

What's included
  • Utility-specific application forms
  • Technical specifications
  • Single-line diagram for utility
  • Site plan and equipment details
[Interconnection Application Sample]

Commissioning Plan

Detailed commissioning plan and procedures for system startup, testing, and verification. Ensures a smooth transition from construction to operation.

What's included
  • Step-by-step commissioning procedures
  • Testing protocols and acceptance criteria
  • Equipment verification checklists
  • Documentation and sign-off forms
[Commissioning Plan Sample]
Examples

Sample Deliverables

[ Sample: Single-Line Diagram ]
[ Sample: Three-Line Diagram ]
[ Sample: PE Stamp Certificate ]
[ Sample: Interconnection Package ]
[ Sample: Commissioning Plan ]
[ Sample: Structural Stamp Report ]
Process

How It Works

01

Define your scope

Tell us exactly what you need — SLD, stamping, interconnection app, or any combination.

02

Specialist assigned

We match your project with an engineer who specializes in that deliverable type.

03

Draft for review

Review the deliverable in-platform. Request changes or approve for final stamping.

04

Stamped and delivered

Receive your PE-stamped, utility-ready, or AHJ-ready deliverable.

Piecemeal vendors vs. PhaseOne

The Old WayWith PhaseOne
PE stampingSeparate stamping firm, extra costAvailable in all 50 states through one team
InterconnectionYou fill out utility formsComplete package prepared for you
Turnaround1-3 weeks per vendor1-4 days
CoordinationManage multiple vendorsOne team, one platform
RevisionsEmail back-and-forth, extra chargesIn-platform, revisions included

Transparent, fixed pricing

Specialty Engineering starts at $149 per deliverable. No hidden fees, no surprise invoices. PE stamping is always included.

Starts at $149
PE stamping included
No hidden fees
Volume discounts available
YOUR FIRST DELIVERABLE IS ON US

Sign up and get your first deliverable free — no credit card required.

We used to juggle three different firms for stamping, SLDs, and interconnection docs. PhaseOne handles it all under one roof with better turnaround.
RT
Rachel Torres
Helios Engineering

Related Services

Ready to get started?

Book a call and we'll scope your first project together.

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