I have been looking at various smart locks, Yale being an obvious choice, and i was thinking about an alternative workaround…
In theory, could an electro magnetic opener, controlled from, for arguments sake a Fibaro relay with a 12v supply connected be activated from an on/off switch from a device or possibly even a presence sensor?
So, you arrive home, presence is detected and the relay will switch on for a pre determined time of 5 seconds (or whatever you select) activating the electromagnetic opener, allowing you access.
Is this theoretically workable, obviously with a little light smartapp manipulation?
Some community members have done that. One did a project write up.
The biggest complexity is over what is the device’s behavior in a power outage.
US code in most areas require that doors on buildings where people sleep be able to be opened from the inside in the event of a fire without requiring an extra key or code or device.
At the same time, most people would like their doors to remain locked from the outside in a power outage to prevent burglary.
This is why most smart locks are deadbolts. It’s easy to have a manual turn bolt on the inside which will work whether the lock is powered or not, but the default is that it is locked from the outside, again whether it is powered or not.
As soon as you go to the strike plate mechanism, it’s common to find that allowing it to Open from the inside even when the power is off means it will be unlocked from the outside when the power is off.
So just depends on exactly what you want.
Here’s the project report the other person posted:
That’s my write-up. If you have any questions let me know. I installed an app that locked the door when a door sensor detected it had been opened. (edited to correct words: i posted this from my phone originally)
JD as always has it right, but since nobody specifically said anything yay or nay on the mag lock…
In case of a fire how would you disable the lock? It would need to be fail safe (which if memory serves are most of the mag options available) for fire safety, which would also mean if the power went out your door would be unlocked, is that acceptable?
I would highly recommend not using a mag lock.
There are many retrofit electric strikes that can be used like the posted link they could be set to the favored fail secure (locked when no power) for code/safety (typically, you still should to check local codes to be sure).
But depending on your use case it may be easier/cleaner to use a zwave deadbolt.
Thank for the replies, appreciated - having read the other thread mine requirements are really quite simple in terms of the actual opener and there are no safety implications as the door would function exactly the same as it does now, just with the added bonus of being able to open with a command or presence.
My door lock is as pictured…
And i’d simply be adding…
or similar to give the opening functionality, obviously no voltage would have to be closed and 12v would have to be open but I’ve found this is usually the case. Other than that the function of the app would be the main part of the functionality.
This is what threw me. I thought you were talking about a Magnetic lock which is a common commercial security item, but would definetly need some forethough if it were to be applied in a residential application, not an electric strike - The posted thread has some helpful information in it.
Since it’s for your home Make sure you use Fail Secure, so when you lose power your door isn’t unlocked.
Fail safe operates the opposite, it’s only locked when power is applied.
the strikers are ideal because you still have standard doorknob functionality. I have one of these installed on my front door. 12v releases it, but incidentally you still have to release tension off of it by pulling on the knob before pressing the door open. I suppose this is a safety feature to prevent the door flying open if someone was leaning on it. I have a write-up on how i did it, but basically i have a virtual door lock triggering a real z-wave relay that the power supply is plugged into.
…Which is in turn engaging the release i bought earlier today.
The open/close sensor on the front door switches the relay off as soon as the door is opened which ensures that it remains locked when you close it.
The cost of a FIbaro relay and a 12v release (£24) and I’m quite happy.
