Systemair

Requirements

One of the following Systemair residential air units:

VR400 VR700 VR700DK VR400DE VTC300 VTC700 VTR150K VTR200B VSR300 VSR500 VSR150 VTR300 VTR500 VSR300DE VTC200
Python3 package ‚minimalmodbus-0.7‘ or later. (install it with pip3 or easy_setup).
Python3 package ‚pyserial-3.0.1‘ or later. (install it with pip3 or easy_setup).

If you use a virtual serial device like /dev/ttyVUSB0, sometimes an error occurs:

...
File "/usr/local/lib/python3.2/site-packages/serial/serialposix.py", line 605, in _update_dtr_state
fcntl.ioctl(self.fd, TIOCMBIS, TIOCM_DTR_str)
IOError: [Errno 22] Invalid argument
...

Due to a bug in the current pyserial implementation, you have to change the ‚minimalmodbus.py‘ code and change following line:

self.serial = _SERIALPORTS[port] = serial.Serial(port=port, baudrate=BAUDRATE, parity=PARITY, bytesize=BYTESIZE,
stopbits=STOPBITS, timeout=TIMEOUT)

to

self.serial = _SERIALPORTS[port] = serial.Serial(port=port, baudrate=BAUDRATE, parity=PARITY, bytesize=BYTESIZE,
stopbits=STOPBITS, timeout=TIMEOUT, rtscts=True, dsrdtr=True)

Normally, you can find the file in ‚/usr/local/lib/python3.2/site-packages/minimalmodbus.py‘. (It depends on your python installation, maybe you have to change the python version 3.2 to your needs.)

Supported Hardware

Should be working for all Systemair air handling units. Successfully tested on Systemair VTR 200/B.

ATTENTION: some of the values provides write access to the air handling unit. BE CAREFUL. You can harm your device. You use this plugin at your own risk. Please check the official Modbus document on Systemair’s website:

https://www.systemair.com/globalassets/documentation/40903.pdf

Configuration

plugin.yaml

Systemair:
    class_name: Systemair
    class_path: plugins.systemair
    serialport: /dev/ttyUSB0    # serial port of modbus device
    # slave_address: 1 # default: 1
    # update_cycle: 30 # default: 30sec

items.yaml

The example below contains not all possible modbus register. Many of these values are not necessary for daily use. To get all possible register open the ‚systemair.yaml‘ in the plugin folder. Every item marked with mod_write: true is a writeable register.

Example

Lueftergeschwindigkeit:
    # read/write
    # 0: Aus
    # 1: Langsame Geschwindigkeit
    # 2: Mittlere Geschwindigkeit
    # 3: Schnelle Geschwindigkeit
    type: num
    systemair_regaddr: 101

Luefterdrehzahl_Zuluft:
    # in Umdrehung pro Minute
    # read
    type: num
    systemair_regaddr: 111

Luefterdrehzahl_Abluft:
    # in Umdrehung pro Minute
    # read
    type: num
    systemair_regaddr: 112

Frostschutzlevel:
    # read/write
    # Frotschutzlevel, erlaubte Werte: 70,80,90,100,110,120 = 7,8,9,10,11,12°C
    type: num
    systemair_regaddr: 206

Sollwerttemperatur_Heizregister:
    # read/write
    # Sollwerttemperatur des Heizregisters
    # Werte 0 - 5 beziehen sich auf die Temperaturen von Temperaturlevel1_Heizregister bis Temperaturlevel5_Heizregister
    # anders als die offizielle Beschreibung: Wert 0 ist die Temp. von Temperaturlevel1_Heizregister, 1 von Temperaturlevel2_Heizregister usw.
    # Weitere Werte je nach Gerät (6-29) möglich
    # in Grad Celsius 0:0, 1:12, 2:13, 3:14, 4:15, 5:16, 6:17, 7:18, 8:19, 9:20, 10:21, 11:22 usw.
    type: num
    systemair_regaddr: 207
    mod_write: 'true'

Isttemperatur_Heizregister:
    # read
    type: num
    systemair_regaddr: 208

Temperatursensor_1:
    # read
    type: num
    systemair_regaddr: 214

Temperatursensor_2:
    # read
    type: num
    systemair_regaddr: 215

Temperatursensor_3:
    # read
    type: num
    systemair_regaddr: 216

Temperatursensor_4:
    # read
    type: num
    systemair_regaddr: 217

Temperatursensor_5:
    # read
    type: num
    systemair_regaddr: 218

Wochenprogramm_Aktiv:
    # read
    # 0: aus, 1: ein
    type: num
    coil_regaddr: 6401

Filter_Wechselzeitraum:
    # read/write
    # Wert in Monaten
    type: num
    systemair_regaddr: 601

Filter_Verbrauchte_Zeit:
    # read/write
    # Wert in Tagen
    type: num
    systemair_regaddr: 602

Defroster_Status:
    # read
    # Werte:
    # 0: No defrosting ongoing, 1: Reduced flow defrosting, 2: Bypass defrosting, 3: Stop defrosting
    type: num
    systemair_regaddr: 651

Alarm_Filter:
    # read
    # Werte:
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12801

Alarm_Luefter:
    # read
    # Werte
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12802

Alarm_Rotor:
    # read
    # Werte
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12804

Alarm_Frost:
    # read
    # Werte
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12805

Alarm_PCU:
    # read
    # Werte
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12806

Alarm_Temperatursensor:
    # read
    # Werte
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12807

Alarm_Notfallthermostat:
    # read
    # Werte
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12808

Alarm_Lueftungsklappe:
    # read
    # Werte
    # 0: Alarm nicht aktiv, 1: Alarm aktiv
    type: num
    systemair_coiladdr: 12809

Alarm_Relais_Aktiv:
    # read
    # Werte
    # 0: Relais nicht aktiv, 1: Relais aktiv
    type: num
    systemair_coiladdr: 12817

Workarounds

If you get an error like Modbus systemair 'ascii' codec can't encode character '\xcf' in position 99: ordinal not in range(128) or similar, you can edit the minimalmodbus.py and replace

self.handle_local_echo = False

with

self.handle_local_echo = True

to activate the echo mode.