IHC WindSensor

This project is a wind sensor for my new retractable awning. The box does have an open collector output for my intelligent house controller (IHC by LK).

When the wind does reach a programmable limit in wind speed then the alarm LED turns on and the open collector output then goes active. This will be connected to a digital (24V) input on the IHC controller. The windsensor box is supplied with power from 12-24V (IHC has 24V supply).


Each time the wind rotor turns one rotation (using a reed-relay) it triggers the input and the Pulse LED will lit in a short period of time to indicate a received pulse.


The middle (green) LED is a pulse width modulated LED to show that the box is alive. It turns brighter and darker continously to indicate the program is running.




The box is black wall mountable (buttom flanged lid) made of flame retardant ABS.

The circuit board does have one 6-way plug-in connector.


Pin 1: Supply In (9-24V)

Pin 2: GND

Pin 3: Alarm Output (open collector N.O.)

Pin 4: 0-10V output (analog voltage scaled from 0-30 m/s Wind Strength)

Pin 5: GND

Pin 6: Input from rotor (N.O.)


At the other end of the board there is a RS-232 connector. This can be used for logging and setup of the wind sensor.



The 4-way dip-switch can be used to set wind speed alarm threshold.


0000: debug mode
0001:  1 m/s
0010:  2 m/s
0011:  3 m/s
0100:  4 m/s
0101:  5 m/s
0110:  6 m/s
0111:  7 m/s
1000:  8 m/s
1001:  9 m/s
1010: 10 m/s
1011: 11 m/s
1100: 12 m/s
1101: 13 m/s
1110: 14 m/s
1111: 15 m/s

A setting of in the above table of '1011' means that switch 1 is off, switch 2 is on, switch 1 is off and switch 4 is off.

The board also holds an ICSP connector for in-circuit debugging/programming purposes.


New software can be uploaded using a on-board bootloader.



Wind rotor (Anemometer)

the rotor picks up the wind speed by sending a pulse using a reed-relay (magnetic relay) for every turn the rotor makes. This sensor is sending a pulse every 1 second if the wind speed is 2.5 mph (~ 1.1176 meter/second. This is picked up in the electronic box that i made.

Every second the box is looking at the windspeed 10 seconds back and makes an average calculation. If the wind speed exceeds  the alarm threshold limit set by the dip-switches the alarm out and the alarm LED is set on.


Or simply call my at:


+45 40 68 03 05



New PCB layout

This is the updated version of the PCB. The new board is primary based on surface mounted devices (SMD) and includes both analog and digital outputs.


Big Interest

Due to a big interest and demand for this device a little production has now been initiated.


The design is now primaray consisting of SMD components. A PCB layout has been prepared and PCBs has been ordered from a PCB manufacturer.

Example of serial data received from the box at a setting of 7 m/s for the alarm threshold

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