Bell Wire Q

I will be running standard alarm cable to mine, I will have a reel of it anyway, and the extra conductors may come in handy later! (IF you are connecting it to an alarm, and it is illuminated, I expect you will need to isolate the illumination circuit from the button and power it separately anyway, which will require 4 conductors)

Toby...

I don't think there is a "standard bell wire". It's typically something like 0.5mm diam (0.2mm^2 CSA).

Bell wire will handle everything except mains, but most bell pushes won't do mains, and it's not a good idea to have mains there anyway. If you're going to use an alarm zone and you want a bell push with a light, you'll probably need a separate pair for the light (and to modify the bell push so it's independant -- could fit a tiny LED in the space instead of the more normal festoon bulb). In that case, use 4-core alarm cable (which is .22mm^2 if it conforms to the relevant BS).

It's quite important that the person pressing the button gets some audiable feedback that the bell actually worked, so you don't want the only sounder too away far to be heard outside.

Just in case you don't know, you can now get wireless doorbells. I guess the push button transmitter is battery powered but only on whilst being pushed so shouldn't run down quickly. You can change the sounder's position later without rewiring.

Peter Scott

...and bear in mind that a conventionally wired illuminated bell push will go out when the push is depressed, indicating that the bell circuit has been completed and that won't happen if you wire the lamp separately.

Peter

Bell wire is specifically low voltage only. Rated to 50 volts. If you wish to use a mains bell with a normal bell push which is also low voltage only, you'll need to use a relay.

Bell wire covers all low voltage doorbell uses. If you're burying the wire, and the wiring length isnt enormous, I'd consider using cat5 instead. With its cores parallelled it can do what bell wire does, and it can always be unparallelled later for who know what other uses, eg multi-zone buttons, intercom, etc etc.

NT

Or use multicore alarm cable - 8 core is smaller and cheaper. Unless you already have some cat5.

I used this company to but my bellwire and i also got a new button as well.

They sell it by the meter

Hope this helps someone

Cheers

=A0 =A0 =A0 =A0 =A0 =A0 =A0

=A0 London SW

and spam by the bucketload, by the looks of things.

Any possible option?

I'd suggest 4 x 6mm2 SWA in case you want a motor-driven air-raid siren on the rooftop, and a couble of lengths of Cat5 in case you want an IP voice intercom and an IP CCTV camera.

Owain

I've come across two sets of wall lights wired up with bell wire....

Half of Asia is wired up with it

I've even seen it used for lighting in Austria

thanks for warning us about your dishonesty. It helps me make up my mind to avoid your company.

NT

Sure. But in practice alarm cable is only cheaper if you have other uses for nearly the whole reel, otherwise you're better sticking with cat5. In more or less all cases its better to use cat5, since that enables more future uses... so if you buy just one reel of wire, cat5 is the best option, and if you buy 2... cat 5.

NT

Or the other way round. ;-)

It never ceases to amaze me the uses some find for cat5 - must be the large reels it comes in. ;-)

"Owain" wrote

Excellent - Thanks Owain But I think that's pushing even my "prepare for every eventuality" envelope somewhat!

Phil

Well, bell wire is just a small subset of all the types of "zip" or "figure of 8" wire. Bell wire is normally quite small CSA and solid core. "figure of 8" flex (stranded) was routinely used for appliance cords in this country up to the beginning of the 1970s, and I even recall a triple version of it which my parents had on a kitchen appliance with centre earth (although that was rather unusual). After that date when we adopted EEC (as was) rules, one would occationally see a sheathed version of it (mains cables now needing to be sheathed), but that seemed to die out. Ironically, unsheathed mains "zip" wire continues to be found quite frequently in much of the rest of the EU ;-) and of course, it's absolutely standard in the US, where it seems to be sized to run luke warm in normal use;-).

Don't wire up alarms with cat5 or phone cable. The alarm accessory terminations are explicitly designed for stranded cable (as required by BS somethingortheother), and they turn out to be rather unreliable long term with solid core. That's quite a common DIY alarm mistake.

Back in 1979, company I worked for got a 48kbit/s leased line installed (which was pretty much unheard of at the time, and the fastest available). That cable was 4 x 4mm or 4 x 6mm2 (I forget) SWA. I presume they were two twisted pairs, but I didn't see enough of it stripped to confirm. It required about 1/2 mile of trench to be dug before it got to BT ducts which were big enough to draw it through. I believe it was 5 miles long (Dunstable industrial estate to Luton telephone exchange). We only used it for a short time before deciding it was too expensive and downgrading to 9.6kbits/sec, which went over ordinary phone line pairs. It's probably still buried there though!