this post was submitted on 19 Feb 2024
490 points (99.2% liked)

Technology

60055 readers
3620 users here now

This is a most excellent place for technology news and articles.


Our Rules


  1. Follow the lemmy.world rules.
  2. Only tech related content.
  3. Be excellent to each another!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, to ask if your bot can be added please contact us.
  9. Check for duplicates before posting, duplicates may be removed

Approved Bots


founded 2 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 2 points 10 months ago (1 children)

I would genuinely like to learn about how you deal with stuff like malfunctions and backup door unlock methods. But now I don't really want to discuss much because of health issues. Hopefully you all won't consider me a bad person who likes to argue

[–] [email protected] 7 points 10 months ago (1 children)

Usually, if a building has electronic access control, it's a requirement that the main controller or power supply be directly tied into the fire alarm with a hardwired trigger relay to drop power to all the door locks during an alarm. It may all be controllable and configurable on the cloud, but commercial equipment still has traditional redundancies like standby batteries and the like.

[–] [email protected] 1 points 10 months ago (2 children)

What if there's a gas explosion or another case that causes loss of connection between the system and the doors? Is it possible to open them manually in such cases?

[–] [email protected] 4 points 10 months ago* (last edited 10 months ago)

If the door has no means of mechanical egress, for example, a maglock, then it is required to have a second form of egress that cuts power to the maglock, such as a normally-closed exit button. Maglocks naturally unlock when losing power. Electric strikes and locksets can be set up fail-safe or fail-secure.

[–] [email protected] 4 points 10 months ago* (last edited 10 months ago)

Not the commenter you replied to, but these kinds of systems are usually "fail open": if there is unexpected loss of power (including the locking mechanism connection to the controller being interrupted), the door is released/unlocked, and can be opened manually by users.

Some more complex systems will have specific doors automatically shut in the event of a fire to try and keep it contained, depending on local regulations. These doors can still be manually re-opened, but they will not "catch" or latch open until the system fault is resolved

Edit: add clarity