How to tell which Nest Protect you have

This guide will help you quickly identify if you have a 1st or 2nd generation Google Nest Protect, and if it’s battery powered or wired. All generations and types of Nest Protect are compatible and can interconnect with each other.

There are several ways to tell which type of Nest Protect you have. The table below summarizes what to look for if you're trying to figure out if you have a 1st or 2nd gen Nest Protect. If you need to determine if you have a battery powered or wired model, click the link below to skip to that section.

How to tell if you have a battery-powered or wired Nest Protect

1st gen 2nd gen
Look at the side Straight edges Rounded edges
Look at the design
differences without taking
your Nest Protect off the
ceiling or wall. The most
obvious physical difference
is the rounded profile of
the 2nd gen Nest Protect
compared to the square
profile of the 1st gen. 1st gen protect side view 2nd gen protect side view
Look at the backplate Square Round
If you take your Nest
Protect off the ceiling or
wall, you can immediately
tell by the backplate design:
square
for 1st gen,
round for 2nd gen. Back plate thermostat image Nest Protect gen 2 backplate
Look at the Back No battery door Battery door
2nd gen Nest Protects also
have a battery
compartment door, while
1st gens do not. 1st gen protect back view 2nd gen backplate
Serial number (on the back
label) Serial #: 05A or 05C Serial #: 06A or 06C
protect serial number on the back 2nd gen protect label serial number
Look in the Nest app Model: Topaz 1.x Model: Topaz 2.x

  1. Select the Nest
    Protect icon

  2. Tap Settings .

  3. Select the Nest Protect
    that you want to check.

  4. Select Technical Info.

Nest Protect technical info in the Nest app technical info example

How to tell if you have a battery-powered or wired Nest Protect

You don't need to take your Nest Protect off the ceiling or wall
to tell if you have a battery powered or wired version. If you see
a green light, you have a wired Protect. All wired Nest Protects
(120V and 230V, 1st and 2nd gen) have a green power light on
the front, just above the Nest logo. Battery powered Protects
don't have this green light.

Note: The green light will turn off if there's a wiring problem, if
there's a power outage in your home or neighborhood, or if
power is switched off at the breaker or fuse box.

green light image

Look at the back

If you haven't installed a Nest Protect yet, you can easily tell
whether it's a 120V or 230V, or battery powered model, by looking
at the back. Wired 120V and 230V Nest Protects will have a
power connector.

protect back power connector

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