Where is the serial number on a solar panel?

On the label on the back of each panel. Every panel has its own serial, so record them before or during mounting, while the backs are still reachable.

Where is the serial number on an AC or heat pump outdoor unit?

On the unit's data tag or rating plate, which carries the model and serial number. Indoor units have their own plate.

What is the fastest way to record serial numbers on site?

Photograph each nameplate on install day. Baton turns those photos into a checked register, with the photo kept beside every line.

Where to find the serial number on an inverter, solar panel, battery or AC unit

19 Sep 2026 · 3 min read

Someone is standing in front of a unit right now, looking for a serial number. On a finished site it is usually somewhere awkward to reach.

Solar inverter

The serial is on the rating label on the side or back of the unit. Many inverters also show it in their monitoring app. If a claim is ever raised, it has to be the serial of the exact unit that failed, which matters on sites with several of the same model.

Solar panel

Every panel carries its own serial, on the label on the back. Once the array is mounted the backs face the roof, so the only easy time to read panel serials is before or during mounting.

Battery

On the label on the battery unit itself. Stacked or cabinet systems may carry a separate label per module, and each one counts.

Air conditioner or heat pump

On the data tag, also called the rating plate, usually on the outdoor unit and on the indoor unit. It carries the model and serial, plus electrical and refrigerant details. Manufacturers ask for the serial and model of each piece when you register the warranty.

The rule that saves the most time

Photograph every plate on the day you install. Take it straight on, sharp and fully in frame. A photo you can read later is worth more than a serial written on a scrap of paper.

With Baton, that photo is the whole job. The crew photographs the plate in the browser, two AI models read it, a person checks the serial against the photo, and it lands in your register and your Google Drive.

Quick answers

Where is the serial number on a solar panel?: On the label on the back of each panel. Every panel has its own serial, so record them before or during mounting, while the backs are still reachable.
Where is the serial number on an AC or heat pump outdoor unit?: On the unit's data tag or rating plate, which carries the model and serial number. Indoor units have their own plate.
What is the fastest way to record serial numbers on site?: Photograph each nameplate on install day. Baton turns those photos into a checked register, with the photo kept beside every line.