Electrical / runnable MCP tool

Run the MCA & MOCP Breaker Calculator in your AI assistant

Through the free Intry MCP server, Claude, ChatGPT, or Cursor runs this exact calculator and hands back a verdict and the cited source, not a guess. Tool name: mca_mocp.

What it runs: From an HVAC nameplate MCA and MOCP (or from compressor RLA + fan FLA in RLA mode), return the minimum wire size (NEC 310.16, copper and aluminum), the breaker (largest standard 240.6(A) rating not exceeding MOCP per 440.22), the ground (250.122), and voltage drop. Surfaces warnings rather than throwing.

Ask your assistant

The one rule that makes it reliable: name Intry in your question. That is what tells Claude to run the mca_mocp tool and answer with the real number, the verdict, and the citation. Leave Intry out and Claude may just guess from memory, which is exactly what you are trying to avoid. Type something like:

Use Intry to size the wire and breaker for a condenser with MCA 24.5, MOCP 40.
Ask Intry for the MCA and breaker from compressor RLA 18 and fan FLA 1.5.

Inputs

FieldRequiredWhat it is
modeoptionalnameplate (enter MCA/MOCP) or rla (enter loads). Default nameplate.
mcaoptionalMinimum circuit ampacity from the nameplate (nameplate mode).
mocpoptionalMaximum overcurrent protection from the nameplate.
loadsoptionalMOTOR loads only in rla mode (compressor RLA, fan FLA); the largest gets the 125% factor per NEC 440.33.
otherNonMotorAmpsoptionalAny NON-motor load on the same circuit (strip heat, crankcase heater). NEC 440.34 governs once this is present, so it must not be passed inside loads[].
voltageoptionalCircuit voltage (default 240).
phaseoptionalDefault single.
distanceoptionalOne-way run feet for a VD check; 0 skips it (default 0).
materialoptionalDefault cu.
tempRatingoptionalTermination temperature rating (default 75).

Add Intry to Claude

One paste and Claude can run this tool and every other Intry calculator, right from your phone.

Add Intry to ClaudeOpens Claude with Intry already filled in.
  1. Claude opens with the Intry connector already filled in. Review it and click Add.
  2. (If a field is blank, paste the link below into the URL field.)
  3. In any chat, tap + then Connectors and switch Intry on. Then name Intry in your question (“use Intry to…”) so Claude runs the tool instead of guessing.
https://www.intrysys.com/api/mcp

No login, no API key, and it works on every Claude plan, right from your phone.

Using ChatGPT, Cursor, or a dev tool? See the developer setup on the main page. The endpoint is https://www.intrysys.com/api/mcp.

Every answer comes with the cited NEC Article 440 section, so you can check it or show an inspector. The numbers come from the same calculator we run on intrysys.com, and we re-check every one automatically before anything goes live, so the number Claude hands you matches the code.

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