TFA¶

Feature	Support
Sending
Receiving
Config

Supported Brands

Brand	Protocol
Soens Weather Station	soens
TFA	tfa
Conrad	conrad_weather

Sender Arguments

None

Config

{
  "devices": {
    "weather": {
      "protocol": [ "tfa" ],
      "id": [{
        "id": 108,
        "channel": 3
      }],
      "temperature": 18.90,
      "humidity": 41.00,
      "battery": 1
     }
  },
  "gui": {
    "weather": {
      "name": "Weather Station",
      "group": [ "Outside" ],
      "media": [ "all" ]
    }
  }
}

Option	Value
id	0 - 9
temperature	-39.9 - 59.9
humidity	10 - 99
battery	0 - 1

Note

Conrad

This sensor does not support humidity measurements

Optional Settings

Device Settings

Setting	Default	Format	Description
temperature-offset	0	number	Correct temperature value
humidity-offset	0	number	Correct humidity value

GUI Settings

Setting	Default	Format	Description
temperature-decimals	2	number	How many decimals the GUIs should display for temperature
humidity-decimals	2	number	How many decimals the GUIs should display for humidity
show-temperature	1	1 or 0	Don’t display the temperature value
show-humidity	1	1 or 0	Don’t display the humidity value
show-battery	1	1 or 0	Don’t display the battery value

Protocol

The tfa protocol sends 86 pulses like

498 1992 498 1992 498 1992 498 1992 498 1992 498 4233 498 4233 498 1992 498 1992 498 2241 498 1992 498 1992 498 2241 498 2241 498 1992 498 1992 498 4233 498 2241 498 2241 498 1992 498 1992 498 4482 498 1992 498 4233 498 4233 498 2241 498 4482 498 1992 498 1992 498 4233 498 1992 498 1992 498 4233 498 4233 498 1992 498 1992 498 1992 498 2241 498 2241 498 1992 498 4233 498 2241 498 8466

The next step is to transform this output into groups of 2 pulses.

If we now look at carefully at these groups you can distinguish two types of groups:

498 1992
498 4233

So the first group is defined by a low 2nd, the second group has a high 2nd pulse. So we take either of these two pulses to define a 0 or a 1. In this case we say a high 2nd pulse means a 1 and a low 2nd pulse means a 0. We then get the following output:

000001100000000010000101101001001100000010

Each (group) of numbers has a specific meaning:

ID: 2 till 9
Channel: 12 till 13
Temperature: 14 till 25
Humidity: 26 till 33
Battery: 34 till 35

ID : 00011000 | Channel : 00 | Temp : 011000010010 | Hum : 00111001 | Bat : 00

The ID is defined as a binary number
The Channel is defined as a binary number and specifies which channel the sensor uses
The Temperature is defined as a binary number and represents the temperature (value is given in fahrenheit strating at -90°F). Assuming that the Temp binary value is AAAABBBBCCCC, the formula to calculate the temperature value in °C is

(((DEC(CCCC)*256) + (DEC(BBBB)*16) + (DEC(AAAA))/10) - 90 - 32) * (5/9)

The Humidity is defined as a binary number. Assuming that the Hum binary value is AAAABBBB, the formula to calculate the humidity percentage is DEC(BBBB)*16 + DEC(AAAA)
The Battery identifies the state of the battery

ID : 24 | Channel : 1 | Temp : 18.56°C | Hum : 57% | Bat : OK

This protocol was created for pilight with the help of this thread: http://forum.pilight.org/Thread-New-Protocol-Wireless-Indoor-Outdoor-Weather-Station-with-3-Sensors

Comments

This weather station or just the sensor is available from several (mostly Chinese) suppliers on eBay or Alibaba. Description for device is usually like: “Digital Wireless Indoor/Outdoor Weather Station with 3 Remote Sensors”. The sensor can be identified by the option to choose from 3 different channels.

Humidity and battery are supported by this protocol. The battery function is not tested 100%. Please be aware that the ID of a sensor changes after you replace the batteries. Conrad sensor only provide temperature (no humidity).

Table Of Contents

TFA¶