Low Cost, Hidden Cupboard Lock

Hardware
1

I have a series of cupboards in a rental property that I’d like to secure in an unobtrusive way and remotely lock and unlock. I’ve seen DrZzs lock (https://www.youtube.com/watch?v=M76g81G3bi8) but it’s a bit more than I need.

I’m wondering if anyone has built something similar that would secure a cupboard door (ie. won’t require much holding force) and ideally is linked to Home Assistant is battery powered. Also, since I need 10 of them, I’d like them to be reasonably cheap. And finally, as the last requirement, I’m in Australia, so I’m limited on the z-wave frequency.

2

I know Ikea is currently rolling out a drawer lock called Rothult, it’s only NFC though, so won’t let you control it remotely but at least it’s battery powered and as far as I gather can be mounted fully inside the door/drawer.

Would probably be a nice starting point for an ESP8266/32 conversion though…

3

Is this also in Australia?

we dont even have the tradfri stuff down under yet…

1 Like
5

Since the Smart Ikea stuff isn’t available in Australia, I did a bit more digging. I found a lock

and a controller

https://www.ebay.com/itm/DC-12V-433MHZ-Motor-Linear-Actuator-Controller-Wireless-Remote-Control-Kit-Lift-/292663905910

which I should be able to control with a RF blaster (which I already have for other controls).

Any thoughts?

1 Like
6

Its a very ghetto DIY solution :frowning:

Ill keep looking for low cost locke, the electromagner will also be quite large and unsightly, and requires constant power to stay locked (if powers out the lock isnt engaged) plus its constantly drawing current = $$

7

How big are the doors on the cupboards?

8

Cabinet height is approx. 50cm/20in

9

I’m not too concerned about visuals, since it’ll be inside the cabinet, so long as it doesn’t get in the way. I’m thinking I’ll mount it on the upper edge of the cabinet, since they’re high cabinets

I agree. Ideally I’d like something that only requires power to lock/unlock rather than requiring power to remain locked, however that doesn’t give any failsafe, since if the power (or something else to do with the lock) fails then the locks remain as they were, which is probably locked.

10

Take look at how I modded a cabinet lock to be RF controllable.

11

That looks slick and pretty much exactly what I want.

Two questions:

  1. Have you found the Broadlink to be reliable? I have one but find it to be a bit flaky for controlling fans. Perhaps it’s just the fans?
  2. How did you record the RF signal for Broadlink? With the fans I press a button on the remote, but with this proxcard sort of set up there’s no button. Perhaps it’s just my ignorance?

Thanks!

12

Thanks.

  1. Yes, I find it to be reliable. Some times it doesn’t ‘work’ and it’s hard to know whether it’s the transmitting, or the recieving that fails. I think it’s the latter. What I do is build in some repeating routines like this. IThen I find my various RF devices very reliable.
close_shed_door:
  sequence:
  - service: switch.turn_on
    entity_id: switch.release_shed_door
  - delay: 00:00:04
  - condition: template
    value_template: "{{is_state('binary_sensor.door_window_sensor_158d000309c34e', 'off')}}" 
  - service: switch.turn_on
    entity_id: switch.release_shed_door
  - delay: 00:00:04
  - condition: template
    value_template: "{{is_state('binary_sensor.door_window_sensor_158d000309c34e', 'off')}}" 
  - service: switch.turn_on
    entity_id: switch.release_shed_door
  - delay: 00:00:04
  - condition: template
    value_template: "{{is_state('binary_sensor.door_window_sensor_158d000309c34e', 'off')}}"
  1. You can basically use any cheap transmitter/remote (that often come with the RF relay/controller) and teach the broadlink that signal. Then teach the RF reciever the same signal either from the remote or by triggering the Broadlink. In fact you don’t even need the remote. You can just find some signals on the forums and use them. If that makes sense…
13

For question #2 I was referring to the proxcard solution you used (I’ve got fans working already). Since there’s no button how do you record it? Is it a matter of holding the card near the BroadLink to simulate pushing a button? I don’t really know how it works…

The solution for question #1 is a bit hacky but if it works then all good!

Thanks

14

All RFID card related parts get ripped out of the cabinent lock device, discarded, and replaced with a RF reciever/relay.

RFID and RF are very different technologies. I was intially hoping to somehow trigger the RFID card reader remotely, but I don’t think this is possible.

So my solution requires quite a lot of modification.