Door bell volts drop?

[Duncan Bennett]

This one is doing my head in.

installed a 12v transformer. Ran 3 pair telephone cable to an underdone bell and through to a press switch (not illuminated). maybe 20 metres in all.

connect it all up and .... Nothing?

Getting 12v on the output of the trannie and 12 v at the bell.

disconnect the circuit going to the push. Now it's just a 6m run from the bell straight to the trannie. getting a slight trembling at the bell.

Take the bell off and connect it through a metre of cable to the trannie and it's fine.

i've changed the trannie and doubled up on the telephone cable cores, but still nothing. Am I missing something?

 

[Darkwood]

Is the transformer big enough to run the bell ?
The dome bells are not usually true circular and the strength of trembling can be changed by adjusting the orientation of the of the dome if its not set up right it wont reach at all....

 

[shocking_eg]

you aint getting no volt drop lol

sound like the bell needs adjusting using the screw on the front.... either too tight or loose

 

[snowhead]

Getting 12v on the output of the trannie and 12 v at the bell.

Is that with the bell connected?

Is the bell A.C or D.C?

 

[Octopus]

I recall some manufacturers have limits on how far they recommend between push and bell. 20 meters sounds a lot.

 

[Duncan Bennett]

Thanks all.

i've installed hundreds of these on domestic jobs, but this is a shop where they want to call from the till to get people through from the back shop.

while I was getting 12v at the bell, my multi-meter is on another job and I was using my voltage tester and assumed it wouldn't show 12v without it being there.

on reflection, 20 metres is probably a bit far for the trannie to push, but there just isn't an alternative - shorter - route. I might try using a 12v trannie and test the voltage to make sure it won't burn out the bell - assuming it will push 8-12v over the distance.

 

[chrish_1977]

You could try a bigger transformer, perhaps 14v. But you need to check that you are getting 12v at the bell after adjustment of coursr

 

[Duncan Bennett]

Cheers, Chrish

 

[Guest111]

As others have said turn the bell dome as follows,get someone to hold bell push down while you turn the dome.That way you can set it properly.

 

[Duncan Bennett]

Thanks, Phil. Tuning bells has been the bane of my life at time - especially working on your own and running back and forward. But the bell isn't getting enough to kick the striker at all. I think it has to be volts drop; I ran the cables myself and installed a new trannie, push and bell.

 

[Guest55]

You could try a bigger transformer, perhaps 14v. But you need to check that you are getting 12v at the bell after adjustment of coursr

did you bother to go back and read the posts in the thread you started in the training section ?
or was i just wasting my time writing my helpful reply ? :-/

 

[Duncan Bennett]

@Chrish. ??? I said cheers for your reply? And what posts in the training section?

 

[Duncan Bennett]

@Chrish. ??? I said cheers for your reply? And what posts in the training section?

Sorry, Chrish. Didn't notice that the post was from Biff 55. I'm lost now :-/

 

[Edd]

stick the tranny near the bell and get a small 6-9 volt relay, Bell push switches the relay at volt droped voltage. relay switches the 12volt that is next to the bell!

 

[Duncan Bennett]

Cheers for that, Ed.

The problem is it's such a daft situation: The original 12v trannie was located about 3m from the push in one direction, and about 5m from the bell in another. But the original bell wire was fed under the floor. I can't get access to the floor, so all I can do is run around the perimeter walls from Trannie, to Bell, to Push - and I guess the 12v trannie just isn't up to it. I've ordered an 8-12-24v unit which will - i hope - do the trick.