Sonoff SPM-Main – Smart Switch LAN RS485 Relay Controller

Professional stackable power management controller for smart distribution boards

The Sonoff SPM-Main is a centralized smart relay controller designed for electrical panels and advanced automation systems. It supports WiFi and LAN control and communicates with expansion modules via RS485, allowing scalable power monitoring and switching in residential, commercial, and industrial installations.

Key Features

• LAN Control: Operates locally without cloud dependency
• WiFi Connectivity: IEEE 802.11 b/g/n (2.4 GHz)
• RS485 Communication: Connects to SPM-4Relay expansion modules
• Scalable System: Supports up to 32 expansion modules (up to 128 channels)
• DIN-Rail Mounting: Designed for electrical cabinets
• Remote Monitoring: Control and monitor via eWeLink app

Technical Specifications

• Model: SPM-Main
• Input Voltage: 100–240 V AC, 50/60 Hz
• Max Current Consumption: Approx. 50 mA
• Communication: WiFi, LAN, RS485
• Mounting Type: DIN-rail
• Dimensions: Approx. 142.5 × 90 × 66.5 mm
• Weight: Approx. 214 g
• Certifications: CE, FCC, RoHS

Applications

• Smart electrical panel control
• Multi-channel power switching
• Energy monitoring with compatible expansion modules
• Local automation systems via LAN
• Integration with Alexa and Google Home

Package Contents

1 × Sonoff SPM-Main Smart Switch LAN RS485 Relay Controller

Keywords

Sonoff SPM-Main, smart relay controller, LAN smart switch, RS485 controller, DIN rail smart module, power monitoring system, eWeLink compatible.