ITEAD Studio’s Sonoff family is a collection of really useful and inexpensive home automation devices which have been featured multiple times on CNX Software with either to stock firmware and eWelink app, or open source firmware developed by the community. I’m using a Sonoff TH16 to control a water pump, a Sonoff Pow to monitor my office’s power consumption, and Karl used some Sonoff switches to control his lights at home. The company has now launched Sonoff 4CH Pro with 4 relays that can be controlled with buttons on the unit, WiFi, or RF remote controls, and comes in a DIN Rail enclosure.
Sonoff 4CH Pro switch specifications:
- Connectivity – ESP8266 WiFi module and 433 MHz receiver
- Relays – 4x HUIKE 230V/10A relays (max 2200W per relays) with NC and NO connection
- Configuration – K5 & S6 switch for mode selection; K6 switch for time selection (0.5 to 4s)
- Misc – 4x user button to turn on/off the relays, 4x LED for relay status, 1x WiFi LED; unpopulated header to program ESP8266 module
- Power Supply – 5 to 24VDC via power barrel or 90 to 250VAC via “push buttons” terminal block
The board comes pre-loaded with a default firmware working with eWelink app for Android and iOS. The company explain there are three modes of operation which can be controlled with K5, K6 and S6 switches for each relay:
- Self-locking mode – Each relay can be turn on and off independently.
- Interlock mode – Only one of the relay can be turned on at a given time. For example if R1 is on, and your press R2 to turn it on, R1 will automatically turn off
- Inching mode – A button press on the unit, mobile app, or RF/WiFi remote control will turn on the relay for X seconds as defined by K6 “delay” switch. This could be useful for locking mechanisms.
You can select modes per relay, for example R1 and R2 set to self-locking mode, and R3 and R4 to interlock mode. The company also explains you can connect two AC or DC motors using two relays per motor with only one motor controllable at a given time.
The device also supports on/off timer, and works with Alexa and Nest. Eventually, there could be open source firmware for Sonoff 4CH Pro with projects like ESPurna or Sonoff-Tasmota, since the company included the header to update the firmware as the did in their previous models.
Sonoff 4CH Pro is not available right now, but is still listed for $22.90 on ITEAD Studio website, and you can register your email to get informed when the product launched. Note that the RF remote is not included, and if you need it you can purchase it for $4.50 plus shipping.
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Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
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