Introduction
A common issue with smart lights and switches is that they lose power when the wall switch is turned off, which interrupts automations and makes remote control impossible. SONOFF's detached relay mode addresses this by keeping the relay powered even if the external switch is off, ensuring continuous control and enabling a smarter use of traditional switches.
What is Detach Relay Mode?
Detach Relay Mode decouples the physical wall switch from the relay. When this mode is active, the wall switch no longer cuts power directly; instead, it simply sends a toggle command. The relay and the connected light remain powered and online, even if the external switch is turned off. In this way, the wall switch functions as a trigger rather than as a physical power cutoff.
Common Challenges Addressed
1. Smart device power outages
In traditional wiring, when the wall switch disconnects power, smart devices (such as smart lights) are completely powered off and offline, making them uncontrollable via the app or automation. Detach Relay Mode ensures that even if a smart device is physically "turned off," it remains powered on—smart controls remain available.
2. Maintain family habits of using traditional switches:
Elderly, children, or visitors may prefer to use wall switches. By enabling this mode:
They can press the switch as usual;
You can still operate it remotely via the mobile app without interruption.
3. Transform a traditional switch into a "smart scene button"
By setting a scene, the external switch button no longer controls the load on or off, but instead acts as a trigger to execute a smart scene (such as opening curtains, turning off all lights, activating home mode, etc.).
Supported Devices
MINIR4 - MINI Extreme WiFi Smart Switch
MINIR4M - MINI Extreme WiFi Smart Switch (Supports Matter)
MINI-D - MINI Dry WiFi Smart Switch (Dry Contact Relay)
ZBMINIR2 - ZBMINI Extreme Zigbee Smart Switch (Neutral Wire Required)
ZBM5 - SwitchMan Zigbee Smart Wall Switch (Supports both No Neutral and Neutral Wire)
How to Enable the Detach Relay Mode
Find it in the eWeLink app→Device Settings→Detach Relay.
Practical Applications
Smart lighting with traditional switches
In many homes, wall switches are still used out of habit. By detaching the relay, the switch no longer cuts power to the lamp but simply sends a signal. This ensures the light stays powered for automation, while the switch itself can act as a remote-style trigger inside the smart ecosystem.Using multi-gang switches as scene controls
With multi-button switches, each key can be reassigned as a scene activator rather than a direct load controller. This makes it easy to launch routines—such as arming security, adjusting lighting moods, or managing multiple devices—with a single press.Integration with entry and access systems
In door control setups, a Detached Relay Mode lets a switch work as a command button to unlock or log entries without ever toggling the actual relay output. This reduces wear on the relay hardware while improving overall safety.Shared or commercial environments
In offices, hotels, or rental units, you may not want occupants to interrupt the power supply directly. Instead, the wall switch can act as an input device, while the automation platform retains central control of the logic and load.
Summary and Outlook
The Detach Relay Mode provides a practical and versatile solution for keeping smart devices continuously available, even if someone operates the physical wall switch. With compatible models such as the MINIR4, MINIR4M, MINI-D, ZBMINIR2, and ZBM5, users don’t have to choose between traditional switch usage and advanced smart control—both can work side by side.
Whether the goal is automating lighting, turning wall switches into scene triggers in shared spaces, or enhancing safety while maintaining control, this feature connects conventional switching methods with modern smart home practices. The result is a more reliable and automation-ready system that integrates smoothly into everyday living.