Sonoff SPM-Main smart switch

The Sonoff SPM-Main smart switch, which enables power consumption measurement and supports connectivity via both Ethernet and Wi-Fi. It can handle up to 128 channels - you can combine it with up to 32 SPM-4Relay switches (4 channels each), which are available for purchase separately. What's more, overload protection prevents damage to your devices. The product is also very easy to install.

Multiple applications

The SPM-Main switch will prove its worth in many different applications. For example, it will allow you to find out how much electricity your tenants use per month, or find out the energy consumption of a shopping center or office. The product will also prove useful in a server room or cryptocurrency mine - the overload protection function will allow you to avoid damaging certain equipment.

Reliable signal transmission

Enjoy the ability to connect devices. SPM-Main communicates with the cloud via Ethernet or Wi-Fi connectivity. It also connects to SPM-4Relay switches via RS-485, so it can provide stable transmission over long distances. Connection problems are a thing of the past!

Power consumption meter

Do you want to check the changes in power consumption in each room in the office? Or do you care to know how much electricity is used by your tenants? With Sonoff it is possible! SPM-Main and SPM-4Relay switches allow you to precisely measure power consumption. You can find all the information in the eWeLink app. This allows you to check power consumption without leaving the house - just reach for your phone!

Overload protection

Increase security in your server room and don't be afraid of damaging your devices. The switch offers an overload protection function. When you activate it, the equipment will automatically shut down when the current, voltage or power reaches the value indicated in the application. A load delay function is also available.

Supports up to 128 channels

One SPM-Main module allows you to control up to 32 SPM-4Relay switches. What's more, each SPM-4Relay offers up to 4 independent channels with a maximum load of 20A each. This means that the SPM-Main can handle as many as 128 channels! This makes it ideal, for example, in a block of apartments, making it possible to check the energy consumption of tenants of rented apartments.

Additional facilities

Now you can save the history of energy consumption measurements from the last 180 days. The switch is equipped with an SD card slot (8-32GB, SDHC). This allows you to export data conveniently and gives you the assurance that you won't lose any important information. Mounting the SPM-Main and SPM-4Relay switches won't cause you any problems either. You can easily mount them on the guide rail. Note: the SD card is not included in the kit.