If you want to have complete control over the electrical installation of your home or business, adding a measuring device to the electrical panel is the ideal move. Whether you want to monitor consumption to reduce your electricity bills, or check the quality of the network (voltage, current) to protect your appliances, the right choice is key.

In this guide you will find everything you need to discover the ideal product for you!

1. Type

• Voltmeter & Ammeter: The basic control tools. The voltmeter measures voltage (V) so you can see whether there are drops or surges from the power grid, while the ammeter measures the current (A) that your appliances are drawing at that moment.
• Kilowatt-hour meter & Wattmeter: They measure power (W) and the total energy you consume (kWh). These are the devices that accurately show how much electricity your home is using.
• Multimeter & Energy Analyzer: The most modern and popular devices. They combine all the above measurements in one device, and most are Smart (Wi-Fi / LAN / Bluetooth). They allow you to view consumption live from your mobile phone, keep a history, and receive notifications.

2. What to look out for

You need to make sure the device is technically compatible with your panel:

A. Number of phases: Single-phase or Three-phase?

This depends exclusively on the supply of your space.

• If you have classic Single-phase power, choose the corresponding device.
• If you have Three-phase power, you definitely need a three-phase device (such as the Shelly Pro 3EM), which uses 3 separate current transformers (clamps/CT) to measure all 3 phases simultaneously.

B. Installation type: Where will it be mounted?

• DIN rail: The most common and correct choice. The device "clicks" right next to the breakers and relays of your panel, like most smart analyzers.
• Door / Flush-mounted: Installed on the outer door of the panel (the sheet metal needs to be cut) or in a special slot. It is mainly used in professional or industrial panels for immediate visibility from the outside.

C. Display type: Analog or Digital?

• Analog: The classic needle-based devices. They are extremely durable over time and in difficult conditions, but they show only one measurement.
• Digital: They feature an LCD/LED display, offer tenth-bit accuracy, and can alternate multiple readings on the same screen (V, A, W).

3. How to shop smart Online

• Size in modules: Each DIN rail device takes up space in the panel, measured in "modules" (the width of a standard breaker). Before buying, make sure there is free space in your panel (e.g. whether the device takes 1, 2, or 3 modules).
• Maximum amps (A): Check the device specifications. If the measurement is done directly (inline), the device must withstand the amps of your main breaker (e.g. up to 40A or 63A). If it uses external "clamps" (Current Transformers - CT), then it can measure much larger loads (e.g. up to 120A) without the current passing through the device itself.
• Smart ecosystem: If you choose a smart energy analyzer, check whether it is compatible with the app you already use for your smart home (e.g. Shelly app, eWeLink, Home Assistant).

Important Note: Installing any device inside the electrical panel requires switching off the main power and must always be done by a licensed electrician for your own safety!