Doesn't make sense!!

[phil94]

Hello everyone this is my first time on this forum and I'm looking a bit help!! I'm starting to think I'm a complete idiot!! (Maybe I am??)

A simple apartment block intercom system, has a 12V AC supply. Is it possible, for a DC door strike to operate properly?? I can't see how it could, but need confirmation?

All help appreciated

 

[tazz]

Phil sorry remove ac 24 as the phones supply the - when you push the phone entry button. From your diragram is the fault that the door is staying open all the time, if so removing ac 24 will sort that

 

[tazz]

Diagram of your pic, hope this explains better

 

[phil94]

Whenever I remove the AC 24 - supply the door strike doesn't operate at all, and whenever the AC 24 - is connected the door strike is always closed but will not release from the phone handsets?
The thing that confuses me is that bell and the speaker all ok perfect, but its just the door that doesn't release?!

What should the AC 24 - be connected to? I know this is probably a nightmare trying to figure this in your head, but any help at all gives me an idea to sourcing the problem

 

[tazz]

No it not a nightmare from your picture a can see whats going on.
when you disconnect ac 24 does the lock stay open ie the door is free to open and close or does it stay locked.

 

[phil94]

It stays open and doesn't close or lock at all

 

[tazz]

Right there is the answer, the wrong lock has been installed, you required a fail secure lock, you have a fail safe unit. You can test this by removing the ac - 24.
there should be not voltage at the lock. When the entry button is pressed on any phone you will then get a voltage at the lock.

 

[tazz]

or a quicker way to test remove ac - 24, and press one of the phones entry buttons...you will find the door will lock until the button is released

 

[phil94]

Aha tazz!!!!! That sounds like the problem!! I will have to try this out tomorrow, but that seems to me what is wrong

So just a quick general question, whenever you want to be able to release the door strike from the phone handsets there HAS to be a fail secure lock installed? Is there any way to wire a normal door strike to operate in the same way?

 

[tazz]

Yes you can use a relay to release a fail safe lock, sounds like the wrong lock was installed and the ac - 24 cable was used to secure the door

 

[phil94]

Yea thats what it sounds like to me, I shall go to the job tomorrow and see if that solves it and I will let you know

Thank you greatly for all your enlightenment, I really appreciate it!!!!!

 

[tazz]

Here to help....thats what makes a good forum

 

[phil94]

Excellent tazz!! Thats what the problem was the wrong type of lock had been installed!! Thanks again for all your help with this, you are a handy person to know

 

[Landril]

Are the push button/s (to release the door) sending a signal (NC when pressed) to the cut the power to the lock?

 

[Landril]

Woops looks like im a bit late with this now its been sorted