EMIT ESP32 IoT Development Board Comes with Temperature & Humidity Sensor, 5A SPST Relay (Crowdfunding)

EMIT ESP32 IoT Development Board

ControlBits EMIT (Environmental Monitoring for the Internet of Things) is a baseboard compatible with DOIT ESP32 DevKit V1 development board and equipped with a temperature and humidity sensor, a relay, a 12-pinGPIO connector, and a MicroSD card. EMIT ESP32 IoT development board specifications: Socket for DOIT ESP32 DevKit v1 board with WiFi and Bluetooth LE connectivity Storage – MicroSD card socket Sensor – AM2302 temperature & humidity sensor with -40° to +80° C and 0 to 99.9 %RH ranges. Relay – 5A SPST relay output with status LED Expansion – 12-pin GPIO header Misc – 2x programmable status LEDs (red & green) Power Supply – 5V via USB on ESP32 board, or external 7-12 V supply via terminal block Dimensions – 81 x 81 mm (PCB only) The board comes with mounting holes so it can be wall-mounted, and an optional enclosure is also available. Some applications for the board include smart greenhouse controller, a central heating thermostat, an environmental […]

Connect up to 32 Relays to Raspberry Pi with a Stackable 4-Relay Board (Crowdfunding)

Stackable Relay HAT Raspberry Pi

People have been playing with off-the-shelf relays on Raspberry Pi boards ever since it was released in 2012, and over the years, some companies have maybe Raspberry Pi-specific relay boards such as Strawberry4Pi and Pi-OT. Two years ago, Sequent Microsystems introduced a stackable 8-Relay board enabling up to 64 relays to be connected to a single Raspberry Pi board. The 8-relay board only supported 24V/2.5A, and the company is now back on Kickstarter with a 4-relay board with 250V/10A line-switching relays that can offer up to 32 relays by stacking 8 boards connected to one Raspberry Pi board via the 40-pin I/O header. The board comes with four Songle 250V/10A relays, 3-pin pluggable connectors that accept 18 to 22 AWG wires, and a 5V/3A power supply is recommended. If you stack multiple relay board a beefier power supply may be required. Here are some power consumption numbers provided by the developer: All relays OFF: 10 mA @ +5V All 4 […]

Strawberry4Pi Enables Home Automation on Raspberry Pi Boards (Crowdfunding)

Strawberry4Pi Boards

Strawberry4Pi is an ecosystem of hardware, firmware, and software to create home automation and IoT projects with for Raspberry Pi boards. The project offers a pre-configured Linux operating system, a mobile app for Android and iOS, as well as two boards with four relays: Strawberry4Pi baseboard Zero for Raspberry Pi Zero (W), and Strawberry4Pi shield A/B for the larger boards such as Raspberry Pi 3 Model B+ or Model A. Strawberry4Pi boards specifications: 4x SONGLE relays Misc – Temperature sensor and Wifi configuration button Power Supply Baseboard Zero – 100V-220V via 3-pin terminal block Shield A/B – 5V via 2-pin terminal block Dimensions Baseboard Zero – 97 x 75 mm Shield A/B – 65 x 56 mm Certifications – CE/FCC A 3D printed case and a DIN rail mount are also offered as options. There’s no a whole lot of information about the operating system as most people won’t need to mess with it, but I suppose it’s either based […]

Seeed Studio Introduces 1 to 8 Channels Grove I2C Solid State Relay Modules

I’ve been playing with products or boards with AC relays for a while, but I never really cared to check about different types of relay. So far, all platforms I tested came with largish blue or black boxes which are SPDT electro-mechanical relays. But as I browsed through Seeed Studio, I found some weirdly-shaped relay modules, much thinner than usual, and fairly more expensive. The main difference is that those are solid state relays, and the boards also include a grove connector that allows microcontrollers or other boards to control the relay over a simple I2C connection. The modules are available in 1-channel, 2-channel, 4-channel, and 8-channel  versions with the following specifications: MCU – STMicro STM32F030F4P6 Arm Cortex-M0 micro-controller Relay –  Omron G3MC202P module Input Voltage – 4~6V (Rated Input Voltage: 5V) Load Voltage Range – 75 to 264 VAC 50/60 Hz Rated Load Voltage –  100 to 240 VAC 50/60 Hz Load Current – 0.1 to 2 A Leakage Current […]

XH-M452 Board Helps Controlling a Cabinet or Room’s Temperature & Humidity


XH-M452 is a board designed to control the temperature and humidity in a room or cabinet. It comes with two relays to control appliances like fans, air conditioners, (de-)humidifiers, or heaters, and ships with a temperature and humidity probe attached to a one meter cable. XH-M452 board specifications: “ST Controller” Relays – 2x SONGLE 10A/250VAC 125VAC relays for temperature control (left) and humidity control (right). Display – 2x LED display for temperature & humidity Sensor 1 meter probe for temperature & humidity Temperature range – -20 to 60°C +/- 0.1°C Humidity range – 0% to 100% RH +/- 0.1% RH Misc – +/- buttons to adjust temperature and humidity; 2x relay status LEDs. Power Supply – 12V via terminal Dimensions – 65 x 55 x 28mm You’ll need to provide a 12V power source for the board, connect an appliance to control the temperature on the left terminals, and an appliance to control humidity on the right terminal. Finally adjust […]

Review of Sonoff RF Bridge, Sonoff 4ch Pro, and Sonoff POW with Sonoff-Tasmota Firmware

Karl here. Today we are going to look at 2 new and one older Sonoff devices. Sonoff RF Bridge – $9.90 433MHz RF to WiFi Bridge Sonoff 4ch Pro – 4 Gang WiFi RF Smart Switch Sonoff POW – Wireless switch with power metering capabilities I spent very little time with the stock firmware on the device. I don’t like the fact that an Internet connection is needed, and I am not in control. As of the time of this writing I found the Ewelink was not configurable enough to meet my needs. There is one feature that is really nice that I could easily see keeping stock firmware. It is the Alexa Skill. It worked. I am also currently reviewing Vobot Smart Alarm Clock with Alexa integration and had no trouble controlling the Sonoff devices with Alexa. But unfortunately I am lazy and want everything automatic so I can’t keep it. With the RF bridge I was unable to […]