SparkQuote NEC calculators

ai.sparkquotePublished by sparkquote.aiOfficial publisherv1.0.1Updated Oct 25, 2026

NEC 2023 electrical calculators: wire size, ampacity, voltage drop, conduit fill, box fill, load.

VerifiedStreamable HTTPWeb executableDeveloper ToolsData & Analytics

Overview

AI-generated overview

Remote MCP server offering NEC 2023 electrical calculators: wire sizing, ampacity, voltage drop, conduit and box fill, dwelling load, panel schedules and bidp.

What you can do
Size conductors and check ampacity against NEC Table 310.16, including small-conductor limits and equipment grounding conductors. Calculate voltage drop, watts-to-amps current and continuous-load values, and Ohm's law and power from two known quantities. Check conduit fill for THHN/THWN-2 in EMT or PVC and minimum outlet box volume. Estimate dwelling service load by the optional method and lay circuits out on single- or three-phase panels with per-phase totals. Price an electrical bid from materials, labor, overhead and a target margin.
When to use it
Useful for electricians, estimators and engineers who want quick NEC-based checks while planning circuits, feeders, panels or bids, without opening tables by hand.
Requirements
Remote streamable HTTP endpoint; no authentication, environment variables or headers declared.
Before you install
Results are calculations from NEC tables and depend on the inputs given; they are not a code inspection or permit approval. Verify against the adopted code edition and local amendments before relying on them for installed work or pricing.

Installation

In SourceWeft

  1. Open SparkQuote NEC calculators in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/ai.sparkquote%2Fnec-calculators/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "sparkquote-nec-calculators": {
      "type": "http",
      "url": "https://sparkquote.ai/mcp"
    }
  }
}

Tools

10

wire_size

Wire size calculator

Minimum conductor size for a circuit: NEC Table 310.16 ampacity at the termination temperature rating, the 240.4(D) small-conductor limits, voltage drop over the run, and the Table 250.122 equipment grounding conductor, increased in proportion under 250.122(B) when voltage drop upsizes the conductors.

Parametersampsrequiredfeetrequiredtemprequiredlimitrequiredphaserequiredvoltsrequiredmaterialrequired

voltage_drop

Voltage drop calculator

Voltage drop for a given conductor size, current and one-way length, single- or three-phase, from NEC Chapter 9 Table 8 circular mils (VD = 2·K·I·L / CM, or √3 for three-phase).

Parametersawgrequiredampsrequiredfeetrequiredphaserequiredvoltsrequiredmaterialrequired

watts_to_amps

Watts to amps calculator

Current drawn by a load in watts at a voltage and power factor, single- or three-phase, plus the 125% continuous-load value.

Parameterspfrequiredphaserequiredvoltsrequiredwattsrequired

conduit_fill

Conduit fill calculator

Percent fill and maximum number of THHN/THWN-2 conductors of one size in EMT or PVC Schedule 40, from NEC Chapter 9 Tables 1, 4 and 5.

Parametersawgrequiredsizerequiredtyperequiredcountrequired

box_fill

Box fill calculator

Minimum outlet box volume from NEC 314.16(B): conductor, device (2 each), clamp and grounding allowances times the Table 314.16(B) volume for the largest conductor.

Parametersawgrequiredclampsrequireddevicesrequiredgroundsrequiredconductorsrequired

load_calculator

Residential load calculator (NEC 220.82)

Dwelling service load by the NEC 220.82 optional method: 3 VA/ft² lighting, small-appliance and laundry circuits, fixed appliances, demand factor, heating or cooling, and the minimum standard service size. Leave an appliance out to count it as 0 VA.

Parametersevhvacsqftrequireddryerotherrangesmallrequiredheaterlaundryrequireddisposaldishwasher

ohms_law

Ohm's law calculator

Ohm's law and power: give exactly two of voltage, current, resistance and power; the other two are calculated.

Parametersiprv

panel_schedule

Panel schedule generator

Lays circuits out on a 120/240 V single-phase or 208Y/120 V three-phase panel and totals the load per phase with the imbalance.

Parametersspacesrequiredsystemrequiredcircuitsrequired

bid_calculator

Electrical bid calculator

Electrical bid price from materials, markup, labor hours and rate, job costs, overhead and a target net margin (price = break-even / (1 − margin)).

Parametersraterequiredhoursrequireddirectmarginrequiredmarkupoverheadrequiredmaterialsrequired

nec_ampacity

NEC Table 310.16 ampacity lookup

Allowable ampacity of one insulated conductor from NEC Table 310.16 (not more than three current-carrying conductors in a raceway or cable, 30°C ambient), before any adjustment or correction factors and before the 240.4(D) small-conductor limits.

Parameterssizerequiredtemprequiredmaterialrequired

Version history

1
  1. v1.0.1LatestOct 14, 2026

Score

83% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts

    Declare a GitHub repository with a README, or serve resource_documentation in the OAuth protected-resource metadata.

  • LicenseNot applicable

    A hosted service is used under its provider's terms, so no license is expected here. This check is left out of the percentage.