The Sonoff SPM-Main control panel is intended for use with the SPM-4Relay expansion module

Sonoff SPM-Main switchboard

One SPM-Main unit can be connected to 32 SPM-4Relays. Each SPM-4Relay has 4 isolated channels for more convenient device control.

You can monitor your energy consumption by checking the eWeLink app on your mobile phone. You get current, voltage and power easily.

Each channel can support a maximum current of 20A, no need to be afraid of high power load. The SPM-Main communicates with the SPM-4Relays via RS-485, which enables multi-terminal and stable data transmission over long distances. When the overload protection is enabled, it can protect your devices from burning out.

THIS PRODUCT IS A BASE DEVICE. SPM 4-RELAY devices are sold separately.

All of them fit on the DIN rail of the electrical cabinet and provide smart control and power measurement function with max. capacity 20A per gang, plus overload protection for all gangs. It is a high-performance professional smart home tool for managing homes, office buildings, industrial buildings or even shopping malls to monitor the energy consumption of residents or tenants.

The main SPM device communicates with the eWeLink cloud via Ethernet or Wi-Fi, and with the SPM-4 relay modules via RS-485, which enables multi-terminal and long-term data transmission. One main unit can work with up to 32 units. 4 relay blocks, so total support for 128 x 20A channel control and power measurement.

The device has an SD card slot, you can insert an SDHC memory card (not included with the product) to save up to 180 days of consumption data and check the data via HTTP API. Data can also be exported.

Product features:
Remote On/Off - Anytime, anywhere, you can now turn all channels on and off remotely.
Ability to add up to 32 units. 4-channel power measurement relays to the main channel, total support up to 128 independent channels
Suitable for DIN rail
SD Card Support: Supports adding an 8GB-32GB SDHC memory card to store up to 180 days of usage data
Independent channel management
Physical on/off buttons on 4 relay units
Overload protection for all channels
Mobil App - Free iOS and Android Mobile App: eWeLink Connecting to eWeLink IoT Cloud
Sync Status - Check the actual status of the relay (on or off) using the mobile app
Share control - Control your device with your family