# Panels and service upgrades

> Panel swaps, 100 to 200 amp upgrades and subpanels. Ask with your Sheet attached: homeowners who’ve done it and verified pros answer, and anyone can read it.

## Before you ask

The panel’s brand and size now, what you’re adding, and a photo of the panel label.

- **Attach your Sheet** so people see your sizes and the math.
- **Your town is enough.** Never your address; check photos for house numbers and plates.
- **Is it safe?** A safety question here goes to pros verified in electrical work, unless you pick another trade. Only they can call it safe or unsafe.

## Panel or service upgrade

100 A to 200 A service: 4/0 AWG Al conductors, a 40-space panel, 20 breakers and the grounding (2 rods).

What people get wrong:

- **A meter base the utility won’t accept.** Each utility has an approved list; the wrong socket means a second disconnect day.
- **Sizing from the panel on sale.** The service size comes from the load calculation, not from what’s in stock.
- **Loose aluminum lugs.** Under-torqued aluminum terminations overheat: torque to the label and use the compound where the lug calls for it.

[The worked example, every line's math and the code notes](https://studsheet.com/sheets/panel) · [Your own sizes in the app](https://app.studsheet.com/p/panel)

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- [Every group](https://studsheet.com/forum#every-group)

## How the community works

- **Open to read** from anywhere, no account needed.
- **Sign in with your email** to ask, answer and vote. No password.
- **The best answers rise:** votes, “worked for me” and a solved mark. Verified pros carry a badge.

Questions? Write to [support@studsheet.com](mailto:support@studsheet.com).