Alecto WS1700¶

Feature	Support
Sending
Receiving
Config

Supported Brands

Brand	Protocol
Alecto WSD17	alecto_wsd17

Sender Arguments

None

Config

{
  "devices": {
    "weather": {
      "protocol": [ "alecto_wsd17" ],
      "id": [{
        "id": 100
      }],
      "temperature": 23.00
     }
  },
  "gui": {
    "weather": {
      "name": "Weather Station",
      "group": [ "Outside" ],
      "media": [ "all" ]
    }
  }
}

Option	Value
id	0 - 9
temperature	-50 - 70

Optional Settings

Device Settings

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

GUI Settings

Setting	Default	Format	Description
temperature-decimals	2	number	How many decimals the GUIs should display for temperature
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

Comment

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.

Please be aware that the ID of a sensor changes after you replace the batteries.

Protocol

The protocol sends 74 pulses like:

540 1890 540 3780 540 1890 540 3780 540 3780 540 3780 540 3780 540 3780 540 1890 540 1890 540 3780 540 3780 540 3780 540 1890 540 1890 540 1890 540 1890 540 1890 540 1890 540 1890 540 3780 540 3780 540 1890 540 1890 540 4050 540 1890 540 4050 540 4050 540 1890 540 1890 540 4050 540 1890 540 3780 540 1890 540 3780 540 3780 540 9180

There first 8 pulses are the header and the last 2 pulses are the footer. These are meant to identify the pulses as genuine. We don’t it for further processing. The next step is to transform this output into 36 groups of 2 pulses (and thereby dropping the footer pulses).

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

540 1890
540 3780

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:

010111110011000000011001011001010111

Each (group) of numbers has a specific meaning:

Header 0 till 3
ID: 4 till 11
Battery: 12
TX mode: 13
Channel: 14 till 15
Temperature: 16 till 27
Humidity: 28 till 35

0101 11110011 0 0 00 000110010110 01010111

The ID is defined as a binary number
The Battery identifies the state of the battery
The TX mode defines whether the signal was sent automatic or manual
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
The Humidity is defined as a binary number and represents the humidity

This protocol was created for pilight with the help of this thread: http://forum.pilight.org/Thread-Fully-Supported-No-brand-temp-humidity-sensor

Table Of Contents

Alecto WS1700¶