dbus-p1

A Venus driver that reads the utility gas meter readings from a Dutch energy meter. Using the P1 serial port, DSMR spec.

This code was used with a simple USB-P1 cable straight between GX Device & Dutch Smart Meter as already installed in my house by our utility. No Carlo Gavazzi meters, or interface boxes or anything else involved.

DSMR is short for Dutch Smart Meter Requirements, somehow related to NTA8130.

The Python code in the repo is basically a wrapper around the nrocco/smeterd repo.

Adding the power meter readings as well will be trivial. But since my (Dutch) Smart Meter only sends an update every 10 seconds, which is too little for proper ESS operation, I have not bothered to implement that, yet. Apparently the (recent) DSMR 5 spec increases the update rate to 1 Hz, which is better and will work somewhat, but still work not as good as our EM24 meters, that update twice a second (& have low latency).

tested meter & cable

Below explained mod of the serial-starter depends for the ID_MODEL USB property to equal P1_Converter_Cable. Which is (probably) the P1 Converter Cable V2 as sold here: http://www.smartmeterdashboard.nl/webshop.

I tested it on a Landis + Gyr E350 ZMF110CCtFs2 3-phase meter, with a DSMR 4.2 module.

installation

Requires Venus v2.12~21 or newer: relies on pyserial.

See here for how to obtain root access to Venus.

Step 1. Install crcmod

dbus-p1 depends on crcmod (for the crc16 calculation). Find the installable ipks in the crcmod folder. For Venus running on a raspberrypi2 take the cortexta7 file, for ccgx and beaglebone take the cortexa8 one. Copy the file to the target and install with:

opkg install python-crcmod_1.7-r0_cortexa7hf-vfp-vfpv4-neon.ipk

Step 2. Install dbus-p1

Clone this repo, and its submodules(!). Copy the whole thing over to the Venus device. And run it.

FIXME: add instruction on how to make it get started at boot, or even better, add it natively to serial-starter.

Step 3. serial-starter mod

Modify /opt/victronenergy/serial-starter/serial-starter.sh line 94: Add P1_Converter_Cable to the list of ignored ids. After the change that line would look like this:

        USB-Serial_Controller_D)
            echo cgwacs:gps
            ;;
        ignore|P1_Converter_Cable)
            echo ignore
            ;;

Background details here.

And instead of making serial-starter ignore the dbus-p1 script it would be even better to make it auto- start the dbus-p1 script. Not that hard: go for it!

dsrm info

DSMR2 & 3 meters:

• 9600 baud
• Even parity
• 7 Data bits
• 1 Stop bit
• Wel/Geen xon/xoff
• No rts/cts

DSMR 4 meter:

• 115200baud
• no parity
• 8 Data bits
• 1 Stop bit
• Preferably enable xon/xoff
• No rts/cts

source SmartMeterDashboard.nl