siren

Shelly Plus 1 DIY 12V Siren Driver

budget Discontinued local: excellent Wi-Fi

Price: $42 verified Sep 6, 2026
HA fit: excellent
Works offline: yes
Setup: advanced
Hub needed: no

Discontinued. The manufacturer no longer sells this one new, so a retailer link here can land on remaining stock, a used or refurbished unit, or a successor model - check what the listing is before buying.

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Shelly Plus 1 relay module in front of its retail box, screw terminals on top and the SW/12V/L/N wiring diagram printed on the blue case

Quick verdict

Shelly has discontinued the Plus 1 relay this build is based on, and its US store sells the Shelly 1 Gen4 as the current version; the same wiring works on that relay. A Shelly relay wired to any 12V piezo/strobe turns a cheap industrial siren into a fully local, hub-free Home Assistant siren. The Shelly relay is controlled directly over the LAN by Home Assistant with no cloud dependency. Just note: DIY wiring required; not a turnkey siren.

Notes last checked Jun 2, 2026.

Compatibility snapshot

Home Assistant excellent

Apple Home none

Google Home none

Alexa none

Works offline yes

Setup advanced

Extra hub needed no

Power mains/12V

Local control facts

Home Assistant: shelly integration, Local Push, Platinum on the quality scale (home-assistant.io, checked Sep 10, 2026)

Why it stands out

100% local control with Shelly's HA integration and auto-discovery
Use any loud 12V wired siren/strobe, indoor or outdoor
No additional hub; runs even if internet is down

Reasons to hesitate

DIY wiring required; not a turnkey siren
On/off only (no tones/volume) unless the siren supports it
You must source the physical siren/strobe separately

Best for

Tinkerers wanting a loud, cheap, fully local wired siren

Avoid if

you want a finished, plug-and-play product rather than a DIY/wiring project

Privacy and local-control notes

The Shelly relay is controlled directly over the LAN by Home Assistant with no cloud dependency.

Home Assistant support: supported · integration path: Shelly (local).

Buying reality check

Price notes: The Shelly Plus 1 relay itself is about $42 on Amazon (verified 2026-09-06). The 12V siren or strobe is a separate purchase, so price the pair together rather than the relay alone.

Verified price reads: lowest seen $42, latest $42 on Sep 6, 2026.

Sep 6, 2026$42amazon
Aug 28, 2026$42amazon

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Verified against

The compatibility notes above have not been through the source audit yet. The manufacturer's page is here; the notes were last checked Jun 2, 2026.

Spotted something wrong? Report an error on this page and I will check it against the source and fix it.

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