Bell wire and transformer

[Echo the husky]

Oops you are of course right! It was 10 years ago, memory not good. There was a 2 pole relay used to prevent that problem with the 2 commons connected to 0V, the relay coil was fed from the 12V tap, switched with the bell push. Of course the relay could switch the 2 voltages but it had to be the 0v in this setup for some reason, perhaps there was not enough cores for the layout of components or existing wiring or something.

 

[ericmark]

Bell boxes. The thing that goes ding dong!

That changes things, mine uses 8Ω speakers, with the ding dong type they even overload a standard transformer with one bell, it relies on the user not holding his finger on the bell push, if all the same rated at 8 volt then using a 24 volt supply and wired in series would work, the bells are only a coil of wire there is no contact in them to make then ring.

However that means getting a 24 VA transformer, in fact does not matter is 8 volt or 24 volt, still need a 24 VA transformer and most bell transformers are rated 8 VA. I did look found these at £51.54 plus vat trade. The point of course as soon as you start to look at modifying then one has to ask what about a 3 volt DC power supply to a wireless unit?

I tried these

it seemed great, it seems at first glance that this version would do you. However having tried to use it with a DECT phone it seems with a standard phone the door bell is registered as one phone so pushing door push is like ringing an internal phone, and you have to set which of the three phones it rings, which is not what you want.

So before buying give them a ring and ask if pressing door bell rings all three phones, it may be the phones in the kit are not the same as standard DECT phone, it may ring all three, but check.

The idea was my mother could answer the door bell and find who was there before she transferred into her wheel chair and went to door, so she did not need to answer the door to those religious hawkers. However she never got the hang of it. But where the bells need to be spread around the house then we should expect it to take some time to answer the door, so talking to people at door before answering does seem to be a good idea.

Do a hunt for door entry systems rather than door bells and you may find what you want.

 

[ban-all-sheds]

Definitely over thinking this ... Another option if the wiring will be very long is to use 3 bells with self contained mains transformers, then an ELV circuit where the bell push operates a small relay in each of the bells in place of a bell push.

And that's not over-thinking?

You wouldn't do that if you wanted 3 lights to be turned on and off by 1 switch, so why do it for 3 bells?

 

[JohnW2]

You wouldn't do that if you wanted 3 lights to be turned on and off by 1 switch, so why do it for 3 bells?

There's no need to do it with (230V) lights, since there is no way that cable runs would be so long and/or cable CSA so small in relation to the operating current, that no discernible light came out of the lights at the end of the cable (c.f. no sound coming out of bell).

Kind Regards, John

 

[ban-all-sheds]

Right.

So a good reason with bells is to do it so that cable runs would be so long and/or cable CSA so small in relation to the operating current, that no discernible sound came out of the bells at the end of the cable is what, exactly?

 

[ban-all-sheds]

Basically what is happening here is that people are looking for any way they can to solve the problem except the obvious one - don't have stupidly long, small, ELV cables.

Stop thinking that an ELV bell cannot be treated as if it were an ELV light.

 

[bernardgreen]

Stop thinking that an ELV bell cannot be treated as if it were an ELV light.

but remember at the same time that the current for a bell may be as much as 1 Amp, how many lamps are 230 watt ( i.e. 1 Amp )

 

[bernardgreen]

Have you never seen outdoor LV switches, sockets, etc?

Of course I have, but very few that were suitable as a bell push on a domestic front door.... If you have seen one such could you post a picture of it.

 

[ban-all-sheds]

but remember at the same time that the current for a bell may be as much as 1 Amp, how many lamps are 230 watt ( i.e. 1 Amp )

How many bells are 230W?

 

[ban-all-sheds]

Of course I have, but very few that were suitable as a bell push on a domestic front door.... If you have seen one such could you post a picture of it.

http://uk.rs-online.com/web/c/switc...9,4294827142,4294876189,4294880952,4294885232

New - http://www.google.co.uk/search?q=outdoor+push+button+switch&source=lnms&tbm=isch

 

[bernardgreen]

How many bells are 230W?

http://uk.rs-online.com/web/c/autom...ns/bells/?sra=p&applied-dimensions=4294685464

has six differnt 230 volt bells for sale.

 

[bernardgreen]

BAS your lonk to the RSA site include button for 5 volts, try applying the search filters. Here are some push buttons raed at 230 volts.

Some 230 volt buttons

but even these need to have a water resistant ( IPx4 or better ) enclosure in which to fit the push button.

Are would be nmore expensive than fitting a DIN rail relay and DIN rail transformer into a suitable enclosure and thus having a 12 volt push button

 

[ban-all-sheds]

BAS your lonk to the RSA site include button for 5 volts, try applying the search filters. Here are some push buttons raed at 230 volts.

Sorry - I started that yesterday, got diverted, came back today and forgot I'd not done all the filtering

Are would be nmore expensive than fitting a DIN rail relay and DIN rail transformer into a suitable enclosure and thus having a 12 volt push button

I wonder why we don't do that for lights. There must be a reason.

 

[bernardgreen]

I wonder why we don't do that for lights. There must be a reason.

It is done, as in my cottage,

Switches power to the lights in one bedroom, the hall and the landing. 12 volt control signal from the lighting controller.

 

[Adam_151]

I am sure like a lot of things, Bell cable is not what it used to be, what you get when you order bell cable often has a smaller CSA than the same as already installed/being ripped out, meaning that although you might not have changed the length of run much, when you come to put back, you might have voltage drop issues you never had before. As normally in this application the bell and tx could be sited together, with a long run to the push, my prefered solution tended to be a relay with a 12V AC coil.