Zigbee gateway for Mercury meters

I have long wondered why, despite the prevalence of Mercury meters and the ability to take readings from them via RS-485, there was no Zigbee gateway for them on the DIY device market. I decided to fill this gap myself.

The gateway is based on a CC2530 chip module and an RS-485 – UART converter module

Since this should be located next to the meter, I decided to supply the power normally from 220 volts, without separate power supplies, for which I use a small power supply from the same ali.

The rest is small things like a power terminal block, wires for connecting a meter, a power regulator, a pair of connectors, a button to turn on the pairing mode and an LED with a resistor.

Next, we take the wonderful EasyEDA and draw a diagram in it:

And the fee:

All that remains is to buy all the spare parts from the Chinese, including boards, wait for them to arrive and solder it all together

There is a slightly different module here, I once snatched them up for cheap at TAO, but alas, they ran out there. But you can also install a regular EBYTE, preferably with a connector for an external antenna.

Well, the final touch, write the firmware, connect to Z2M and see how it all looks now:

551694 is the last 6 digits of the meter serial number. For single-phase, this is its network address. For three-phase ones it’s a little trickier, there are either the last 3 digits if they are less than 240, or two if the three digits are greater than 240.