ZigBee relay on CC2652 at an available price from CBE [eWeLink SWITCH-ZR02]

Igor Mullin
4 min readFeb 15, 2022

On the Chinese site, I came across a ZigBee relay from a previously unknown CBE company. It would seem that there is nothing special here, there are many such offers on the market, but I was surprised by the hardware platform on which the relay is based and of course the price.

This is a translation of my article in Zen. Also, do not forget to read us in other services: Instagram, telegram (RU, EN, DE), YouTube.

I wrote about these relays in my post here (RU) and here (RU). The first thing I noticed was that the device is not based on the Tuya platform, but on eWeLink, later it becomes clear that this relay works with any platform, it’s very nice, this is not accepted now. I immediately bought a ten of such relays and plan to use them massively in my future devices.

Let’s take a look at the packaging:

The package at the back shows a complete list of platforms. Inside the box we can find the relay itself and the instructions.

The instruction has only 2 languages, English and Chinese

And now the most interesting thing is what’s inside?

Inside there is a small board on which there is:
1. Power supply (5V)
2. Power supply (3.3V)
3. Relay 10A 250V
4. Radio module on CC2652

The 5V power supply is necessary for the relay and has a very interesting circuit. The input resistor limits the current and works as a fuse, then a diode bridge. After it there is a capacitor, which is connected to another one through a resistor. Next, we see a controller, an inductance, two diodes and a resistor with a capacitor. The controller is unclear what kind, but it is obvious that this is a step-down converter.

The 3.3V power supply is a regular linear on the AMS1117, it seems…

Relay WL73-S-105DM from WQE. The relay is on 5V, it is switched on from the ZigBee board via a transistor. The reverse diode is present.

And now the most delicious — radio module. This is the cc2652 module from Texas Instruments. This module is very common today and is massively replacing the cc2530, which I planned to see. CC2652 sells for $ 7–8, modules built on it are even more expensive, and here the whole device is for $ 5, just some kind of holiday. A button and an LED are directly connected to the board, as well as a transistor for controlling the relay.

In ZigBee2Mqtt, it is defined as eWeLink SWITCH-ZR02 and has official support.

And that’s it, make your smart home smarter, brighter, more colorful, more informative, set up automation correctly to get maximum pleasure. You can also follow me on other sites: Instagram and telegram (RU, EN, DE), LiveJournal, YouTube (new channel).



Igor Mullin

I´m a Hardware and Software Engineer and a PhD. In my professional activity I focus on such things like smart home systems and electric development.