Shelly Pro 1

Hello everyone,

I would like to install a Shelly Pro 1 to detect the water level via an Easy-Level and receive an email alert when the level is low.
I do not want the Shelly to switch the valve — the Easy-Level already takes care of powering it directly.

Current setup

• Electrical supply: 3×220 V (three-phase)
• Easy-Level: controls a float switch and a solenoid valve
• Solenoid valve: powered directly from the 220 V output of the Easy-Level
• Shelly Pro 1: used only to detect the state via the SW input

Planned wiring for the Shelly

• L (terminal L): Phase L1
• N (terminal N): Phase L2
• SW: Switched phase coming from the 220 V output of the Easy-Level
• I / O: Not used

Objective

Water level detection:

• High level: phase present → Shelly ON
• Low level: phase cut → Shelly OFF → email sent

No short circuit, and no direct control of the valve by the Shelly.

Problem / Questions

I want to make sure this wiring is safe for a 3×220 V network, and that connecting SW to the switched phase that also powers the solenoid valve will not create a short circuit.

• Is this the correct way to connect SW in relation to L on the Shelly?
• Are there any special precautions to take with a three-phase network?
• Do you have a simple and safe wiring diagram for this configuration?

Thank you in advance for your advice and feedback!

Hello,

This is my wiring diagram.
⚠️ Attention: the electrical symbol of the solenoid valve shown in the drawing is not correct.

The Easy Level controls a solenoid valve:

• low water level → valve closes
• normal level → valve opens

The Shelly Pro 1 does not control anything.
It is powered with 230 V (L and N) and is used only to detect the valve status and send me an email when the valve opens or closes.

The Easy Level output (switched live) is connected to the SW input of the Shelly.
Terminals I and O are not used.

Can you confirm that this wiring is correct and safe?

Thank you.

This relay is OK for wiring A