Tonight I've modified a MS13 motion detector and added it to the dryer.
And it works! Now Indigo is able to detect when the dryer is on or off.
I promissed I would take some pictures and here they are:
1. These are the stars of the evening: the MS13 module and a piece of wire. This piece has 3 cores, but I will use only 2 of them.
2. Open the MS13 by removing the 4 screws on the back.
As you can see, I haven't removed the battery cover first, but it is better to do that also.
The green circle shows the location of the LDR. This is the day/night sensor.
3. Remove the LDR by cutting both wires in the middle. Don't bother about remembering which pin was on the left en which pin was on the right. They can be mixed without a problem.
As you can see on the picture, there are now 2 pins waving into the air. The left one was covered in glue. That made it a bit hard to cut the wires, but after cutting with a sharp knife I managed to remove the glue.
Be carefull not to damage the other components on the printed circuit board.
Also be carefull to not cut the wires too short on the LDR side or you will get into trouble on the next step.
4. Solder the wire to both pins of the LDR.
Don't forget to add some isolating tape to prevent both pins from touching.
5. This is a very important step!
Remove the rubber thingy that's used for the antenna wire. This will give you probably enough room to guide the wire into the housing of the MS13.
6. Now it's time to solder the other side of the wire to the two pins on the printed circuit board.
I've used pieces from the outer cover as isolation. After soldering the wires they are moved over the pins.
You'll have to strip about 2 inches of isolation from the wire. If you don't, then the wire will probably be too thick so you can't put the MS13 back together.
7. After moving the isolation towards the pcb, I taped it to the wire so it won't move.
At this point, the modification can be tested. Put the pcb into the back of the housing and insert the batteries.
Configure the MS13 in Indigo (if not done allready) and use your hands to cover the LDR. It should flip from day to night mode. Open your hands to let the light come to the LDR. Now Indigo should show it has gone back to day mode.
8. Carefully close the housing. In the upper left corner you'll have to make sure the antenne wire is not put in front of the screw hole. Also be carefull to guide the attached wire in the housing so it closes without much trouble.
I used a rather thick wire. It's better to use some flexible wire instead.
9. Here's the third star for tonights show: the dryer. The upper LED is lit whenever the power is turned on. For me that's a good enough trigger to start the ventilation.
10. And this is the final setup. The LDR is taped over the LED with ducktape. This will also ensure there is no other light comming in. Only the light from the LED will trigger the MS13 now.
The wire is guided to the right of the dryer using the same ducktape.
From now on Indigo will see if the dryer is turned on.
The next step for me is to define the trigger stuff in Indigo, but that's peanuts.