nt5000-serial

README

nt5000-serial

nt5000-serial is a command line tool to access the Sunways solar inverter model NT5000 via a serial connection.

It's implemented in Go. It provides a command line interface and a simple webserver and can export the metrics via Prometheus.

The implementation is based on the NT5000 module of FHEM, a open source home automation server. It potentially works with other solar inverter models as well.

Features

• Get and set the date and time in inverter
• Get the current data like voltage, current, power, etc.
• Display the data on the console
• Display the data an integrated web server
• Export the data to prometheus
• Includes a emulator that creates some random data

Usage

Find serial ports The first step is to find the serial port to which the solar inverter is connected.

./nt5000-serial serial lists all available ports

Get the current date

If not specified, the default port will be /dev/ttyUSB0.

./nt5000-serial datetime

In order to use a specific serial port:

./nt5000-serial --tty /dev/ttyUSB1 datetime

Set the current date

./nt5000-serial datetime --set

Display error log

./nt5000-serial errors

Display the current data

./nt5000-serial display

Sample output:

Date: Sun Apr 10 21:03:03 2022

Serial Number: 1533A5012345
     Protocol: 111-23

 udc:    497.6 V
 idc:      1.4 A
 pdc:      0.7 kW
 uac:    230.0 V
 iac:      3.2 A
 pac:      0.7 kW
  wd:      0.0 kWh
wtot:    374.0 kWh
temp:     21.0 °C
flux:    210.0 W/m^2

Polling every 5 seconds. Abort with Ctlr+C

Display the data in the web browser

./nt5000-serial web

The visit http://localhost:8080/.

Using the emulator

You need two serial ports. The two ports needs to be connected via a null modem cable.

In one terminal, run the emulator: ./nt5000-serial --tty /dev/ttyUSB0 emulator

In another terminal, run the client: ./nt5000-serial --tty /dev/ttyUSB1 display Instead of "display" you can also run the web server with "web".

Build

go build

In order to cross compile for Windows, run GOOS=windows GOARCH=amd64 go build

And for MacOSX, run GOOS=darwin GOARCH=amd64 go build -o nt5000-serial-macos

Docu

• https://svn.fhem.de/trac/browser/trunk/fhem/contrib/70_NT5000.pm
• https://wiki.fhem.de/wiki/NT5000
• https://medium.com/aeturnuminc/configure-prometheus-and-grafana-in-dockers-ff2a2b51aa1d
• https://prometheus.io/docs/guides/go-application/
• https://biancatamayo.me/blog/docker-add-host-ip/

License

MIT License

Protocol

Taken from https://svn.fhem.de/trac/browser/trunk/fhem/contrib/70_NT5000.pm and https://wiki.fhem.de/wiki/NT5000.

A command, that is sent to the converter, is always 5 bytes long. The converter always responds with 13 bytes.

Read online data

Send: "\x00\x01\x02\x01\x04". Last byte is checksum, 5 bytes in total Receive: 13 bytes in buffer

1. UDC (voltage DC): buffer[0]*2.8+100, unit: V
2. IDC (current DC): buffer[1]*0.08, unit: A
3. UAC (voltage AC): buffer[2]+100.0, unit: V
4. IAC (current AC): buffer[3]*0.120, unit: A
5. Temperature: buffer[4]-40.0, unit: °C - if not connected: \x01
6. PDC (Power DC): ($udc*$idc)/1000, unit: kW
7. PAC (Power AC): ($uac*$iac)/1000, unit: kW
8. Energy Today: (buffer[6] * 256 + buffer[7])/1000, unit: kWh
9. Energy Total: buffer[8] * 256 + buffer[9], unit: kWh
10. Heat flux: buffer[5]*6.0, unit: W/m^2 - if not connected: \x01

Read time

Send: "\x00\x01\x06\x01\x08". Last byte is checksum, 5 bytes in total Receive: 13 bytes

1. year
2. month
3. day
4. hour
5. minute

Remaining 7 bytes are zero, 13th (last) byte is checksum.

Set time

Multiple commands:

1. Set year: "\x00\xff\x32"
2. Set month: "\x00\xff\x33"
3. Set day: "\x00\xff\x34"
4. Set hour: "\x00\xff\x35"
5. Set minute: "\x00\xff\x36"

4th byte is the actual value, 5th byte is checksum

Note: When settings hour or minute, one needs to be added to the value to be set. E.g. instead of 14:00, one needs to send 15:01.

No response.

Read Serial Number

Send: "\x00\x01\x08\x01\x0A"

Response: 12 bytes + checksum

"\x0d" is a fill byte and can be ignored.

Read Protocol and Firmware Version

Send: "\x00\x01\x09\x01\x0B"

Response: 12 bytes + checksum

protocol: first two bytes firmware version: bytes 3-12

"\x0d" is a fill byte and can be ignored.

Read error memory

Send: "\x00\x01\x01\x01\x03" Response: 12 bytes + checksum

Bytes: 1: month 2: day 3: hour 4: minute 5: error code. 0x11 = fault 004 / frequency 6: year

bytes 7-12: next error

byte 13: checksum

Next errors: \x00\0x01\0x02 up to \x00\x01\x05 -> in total there are 10 memory slots.

Read monthly aggregated data

Note: This is not implemented

Read yearly aggregated data

Note: This is not implemented

Prometheus and Grafana

One simple way to visualize the data is to use grafana. Here's a how to using docker containers.

nt5000-serial is running on the host, as it needs access to the serial port. It runs a web server on port 8080.

The prometheus container needs to access the web server of nt5000-serial. Therefore maybe the firewall needs to allow access from the container to the host network. Prometheus is running on port 9090.

The grafana container needs to access the prometheus container. This is done via the host. Grafana is running on port 3000.

To simplify the start process, see ./start-prometheus-grafana.sh.

Configure grafana: http://localhost:3000

• Default username "admin" and password "admin"
• Add data source, prometheus
• Prometheus URL: http://outside:9090
• Import dashboard NT5000-grafana-dashboard.json

The dashboard looks like this:

Shutdown:

docker stop grafana && docker rm grafana
docker stop prometheus && docker rm prometheus