Cat Be Gone
The concept:
- Motion sensor controls 24VAC irrigation valve
- Drip irrigation line sprays cats
- Cats leave
Control system requirements
- motion sensor
- valve controller
It could be free standing, probably easiest, or it could be a Home Assistant thing.
I think it should be free standing and later on it can have a WiFi connection to upload activity data so I can make a dashboard replete with colorful statistical charts. Maybe it can trigger a camera too. Later.
The valve controller can be a dry contact relay with TVS protection against spikes.
It has to be in a water tight enclosure, because we're in Astoria.
24AC transformer at house -> low voltage zipcord -> full wave rectifier -> buck converter (MPJA 30148, up to 40V in, adjust for either 3.3 or 5V output)
TVS
I need one that is around 5.5VDC unidirectional to protect the controller. And a bidirectional one for the valve that's around 36VAC
SMD, more hip or thru hole, easier to wire up
Sources, OpenSprinkler
TVS
- Littelfuse SMBJ43CA SMB suggested by OpenSprinkler, probably a little on the high side voltage wise
- Littelfuse P6KE39CA leaded
I ordered some logic-level triacs from STM that are already overvoltage protected. I also ordered some thru hole TVS diodes in case I go for a dry contact relay set up at some point.
