As promised, some pictures. sorry that it took some time, but I had to dismount the whole thing for this. First, see the hole I mounted on the bottom of the inside housing for the USB connector:
This USB connector is part of the step up converter pcb, so all I had to do is glue that PCB with hot-melt in the right position as shown below: (sorry it can be done much cleaner and I used quite too much hot melt
If you look at the battery compartment you will see the minus connector for the battery in front and the plus wire at the back. These connection points are soldered directly to the PCB using a metal pin.
Since you have to mount a diode from the battery to the PCB to avoid them being (over)charged all the time, I decided to cut the connection pin from the negative battery connection and bend it away because that was the easiest . There I soldered diode D1 between the battery pin and the cat flap PCB. From that same point on the PCB I soldered the other (D2) diode as well, that is connected to the blue minus wire to the step up converter. (see the red circle on the photo above) Notice the diode was fitted in a heat shrink tube to avoid short circuits.
See the schema below: (notice the diode direction. if you decide to cut the plus instead, you should mount diodes in reverse) D1 will protect the batteries from overloading, D2 will protect the batteries from discharging over the step up PCB when no USB power is applied.
When you tune the power to be exactly 6v on the plus and minus on the Catflap PCB, the sensors will work correctly. Tuning is done with the small screw on the step up pcb. tune the pcb to 7v before mounting and fine tune it when mounted.
When the USB power fails, batteries will automatically take over. because of the slight power drop over diode D1, the batteries will power the PCB with just enough to function, but the low battery indicator will be activated. I found that quite useful, when my wife had by accident disconnected the USB charger
Sure eventually provided the replacement catches, but didn’t put a stamp on the envelope, and it turns out replacing the springs is a super fiddly task.
I’ve bought a Pi5, 2 cameras and a servo motor. So I’m somewhat committed to building a working 3d printed catflap now. (Then of course I’ve got to build a cloud with a 2 nines uptime and constant code updates to break local hacks and make everybody’s life hard… )
Obviously it’ll need mains power rather than battery, but I that’s one fewer set of batteries to replace in the house…
Just wanted to say a big thanks to you and some others for your long efforts on this project from Australia.
I came across it wondering if there was a way to sniff the communication between my cat flat and the hub as I ’simply’ want to know which of my 2 cats came inside or went outside faster without some sort of camera training.
Currently it’s looking to be not super feasible for me while I look into this on holiday but I’m keen to keep an eye on this thread. Maybe SurePet will do better in the future (unlikely ), but thank you none the less
I have been in contact with a company manufacturing cat flaps (in my opinion they might have built the best cat flap available at the moment), and the best part is that they are really open to work with us to build a local integration with Home Assistant.
I don´t want to disclose too much information about them yet, but just to give you an idea of their level of commitment, they have agreed to send me a catflap for free with the only condition that I help build the integration with Home Assistant.
This might completely change the story, as we might have finally found an alternative to SureFlap and their complete lack of communication or interest in talking with our community about local control.
I will keep you guys posted, and I might need a bit of help to build the integration.
Does this company is also considering making a dual scan cat flap? being able to chose what cats can go in and out is quite valuable.
I have 2 indoors only cats and regular flaps really don’t cut it
While the Surepet one was expensive, it is also really disappointing. In function and support.
So if they offer dual scan which actually functions properly and offer real local only control I’m actually willing to replace my current one.
The commitment of these people is real, I already received the cat flap and it looks amazing, it has dual scan sensors and not only all the functions that the Surepet catflap offers, but also other extra functions. If we can get this thing to work locally with HA we will definitely have the best cat flap in the market.
@pergola.fabio I know some people will not replace their current cat flap straight away considering the money we already paid Surepet for it, but this cat flat might help everyone. For HA users thinking to buy a new cat flat it will be a no-brainer to go with this new model, and even for people who already have a Surepet cat flap, this may push Surepet to discuss with us about this local control we have been asking for years and update their firmware if they don´t want to lose a lot of customers overnight.
@heisenberg I just bought two dual scan cat flaps connect and they cost a fortune… but if what you say is true and the flap ACTUALY WORK, unlike the surepet ones… Shut up and take my money.
I’ll swap both flaps just for how pissed off i am with the lack of quality of the dualscan connect flaps. The regular ones are quite good, but the connect ones are terrible.
If the product is that advanced the communication is probably already decided, but as a wishlist point from me would be standard (not some mangled version of) zigbee, for the power saving capacities.
Also being a tiny bit bigger than the surepet version would be quite welcome by my chuncky one
Great guide, thanks @pdwonline ! ChatGPT advises to use a schottky diode (1N5819) by the way… And using the step-up module doesn’t cause the same issues that occur when using a “normal” power adapter (sometimes invalid or no detection of chip) because the power is stabilized better?
Some ‘normal’ power adapterd will give a higher voltage when not under load. This step up converter will keep up the voltage more precisely. The cat flap is extreme sensitive to over-voltage resulting in faulty operation. This could lead to issues when using re-chargable batteries as well. It seems that the cat flap has no built in regulation by itself.
I put a flag on this topic because I need an electronic cat flap and that I wish for sure connect to my HA but most of all I do not want a cat flat that depends on internet…
The cat flap need to be installed on a double-glazed French window that will be ordered especially for the cat flap dimension so I need a reliable cat flap as I won’t be able to change the hole size for the cat flat later.
So I will wait for this company product. Thanks for the info.
), but thank you none the less
And using the step-up module doesn’t cause the same issues that occur when using a “normal” power adapter (sometimes invalid or no detection of chip) because the power is stabilized better?