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MICKYG
15th June 2005, 07:31 PM
Greetings to all,

With all the chatter and tv coverage re the smoke/fire alarms I am wondering if the 240v alarms with battery back up are actually hardwired in IE: no switching to turn them on or off or are they on a switched circuit. Any sparkies able to answer my enquiry would be appreciated.

Regards Mike :confused:

Landseka
15th June 2005, 08:16 PM
Hi Mike

They DO require a sparkie to install as they are hardwired into the house wiring and are not able to be swiched off.

They should be idiot proof provided the battery is checked occasionally

Regards

Neil.

Pulse
15th June 2005, 08:42 PM
Hi Mike, The ones I have have a baseplate and can be detached to hang from one end of the base plate. They have 240 terminals that the unit slides into, mush like a cordless phone or drill charger. Some have NiMH rechargable back up batteries that charge from the mains. They do need a sparky to wire but pretty straight forward, just wire from a nearby light junction box.


Cheers
Pulse

SteveAndBelle
15th June 2005, 10:30 PM
Mike,

If I were you I'd check the warning on the particular detector you're looking at as I thought all mains conected equipment had to be wired in by a sparky ... maybe I'm wrong (not the first time).

Saying this though they're an absolute breeze to install and wire up yourself with very basic 240V experience but if you're not confident to do this yourself you're obviously best to pay someone to do it. A much safer bet :)

They are not switchable ... they are hardwired to the lighting circuit and have power all the time ... well, except for a blackout which is when the backup batteries kick in.

The ones I have in my house seem to be the same ones 'Pulse' explained above. Standard size detector/alarm which hangs then slides into a bracket on the wall or ceiling which has integrated 240V connectors to give the unit power when in place. They have a row of small NiMH watch type batteries which add up to 8.4V so when one of my detectors started complaining about a dying battery (as they're now about 10 years old) all I did was rip the thing apart and replace the silly little row of 'watch' type batteries with a nice fat 9V NiMH battery as these are actually only 8.4V anyway.

The 9V battery doesn't fit nicely into the enclosure so some modifications have to be made to the PCB but I didn't have the time for that when I was doing it so I just plugged it in as it was and left the battery hang out the side of the case until i have the time. The battery took about 4 hours to charge up and the unit beeped every 10 seconds or so while this was happening however when it reached full charge it stopped beeping and hasn't beeped since. Nice ! It's butt ugly (see pic) but it works perfectly now and that's all that matters to me ... the wife doesn't think so tho. I'll have to get around to prettying that up one day .... one day ...

Another option you might want to consider depending on the wads of cash you've got to blow on such an install is to get a full 'panel' type system. This involves a small 'domestic' panel to be installed ... much like an alarm system panel ... and then all the detectors connect up to it. This requires messy & inconvenient wiring etc. but allows you to only have one power source, the units most probably then each run on low voltage so you can install them as you go or as you can afford them plus it means you've only got a single inexpensive battery backup (a small Sealed Lead Acid 12V battery worth about $30) to look after but that will probably last you 5+ years anyway.

The best bit about a 'panel' based system is that you can set it to do lots of different things ... only sound the alarm on the detector which detected the smoke/heat or get all detectors to alarm at the same time ... send a signal off to your alarm system panel 'fire' input to do 'whatever' ... trigger a circuit off to run some emergency lights to assist in a quick escape ... trigger off a phone dialler to call you and/or an emergency service ... the list is literally endless.

I was looking into installing a 'panel' type system into my current house (a beautiful big 85 year old timber Queenslander ... aka: a fire waiting to happen;) when we bought it only a few months ago however now that I've fixed the current detectors I've put the panel system off for a while. A panel and 10 x detectors (including different types for each application/area) was going to cost around the $1500 mark. Expensive ... yes, but when you consider what it could save the money really doesn't seem important ... except if you don't have $1500 like me anymore ;) Guilty, I bought too many power tools :(

Steve.

Schtoo
15th June 2005, 11:42 PM
Yep, hardwired as you now already know.

If you are buying them new, go for one that has the capability of several being linked to one another. That way, if one goes off, they ALL go off. Noisy as heck, but makes sure that when the garage catches fire, you will know about it early enough to actually do something about it.

Another suggestion if yer on a safety kick is to get Mr. Sparky to wire in a lightning arrestor into the breaker/fuse box. Will stop your new investment in smokies going poof themselves in case of something fishy in the wires. ;)

Just don't ask me to install them. I hate working in houses, I've installed enough smokies to last a lifetime and you can't afford the plane ticket for me to come and do it. ;)

Ashore
16th June 2005, 12:19 AM
In Newcastle NSW you have to have hard wired smoke dectotrs in or adjacent to bedrooms in new extensions

Not sure on the other rules
the unit we had to put in was checked by the building inspector so I had to use a sparky no switching in the circuit, off a lighting circuit not on the earth leakage trip and I must say these rules seamed ok to me
My units do not have rechargeable batteries only the annoying beep beep beep beep 9 volt replaceable types


The trouble with life is there's no background music.

JDarvall
16th June 2005, 12:33 AM
Hi Mike

They should be idiot proof provided the battery is checked occasionally

Regards

Neil.

I can be an idiot........probably should get some installed myself.......but then I'd get unstuck forgetting to change the batterys.........

Thats a eye catching picture you've got there Neil.......congrats on such a successful sex change ......... and you hide your age so well.... ;)

Iain
16th June 2005, 09:28 AM
probably should get some installed myself.......but then I'd get unstuck forgetting to change the batterys.........
When they are low you will get a series of 'Chirps', normally at about 3.00am when the house is at it's coolest, timing is short enough to let you know that the battery needs changing, long enough that you freeze off your wedding tackle waiting for it to go off again while trying to figure out which one it is.
Wait till you get up and the rooms have warmed up a little and they they won't squawk again until 3.00am the following morning, and you know this is going to happen.

Simomatra
16th June 2005, 11:16 AM
Hi Mike

Yes they are easy to install and with little a electrical knowledege no problem but as you allready know they have to be installed by a licensed electrician.

The cost should be minimal as opposed to the results of a fire or smoke damage

Don't forget to test them regularly with test smoke (smoke in a spray can). Should be available at your local electrical retailer. A couple of dollars a tin, lasts forever.

Do not use the test button all the time as this only tests the alarm

Wiring in extras into the circuit is also good advice. More noise the merrier

This will also cover you for insurance purposes if a fire actually got away. Un-licensed electrical work void's insurance in most cases

simomatra

MICKYG
18th June 2005, 01:16 PM
Thanks to all for your comments. I do have battery only installed which are really a pia, The batteries seem to need changing more than they should so hence the idea of 240 with backup. The house is weatherboard and is heated by a LOPI wood heater so the alarms are considered essential. I am researching a suitable 240v model to have installed at the moment and have noted that you can pay a $100 plus each for some. With a bit of luck we will install a reverse cycle air this summer which will perhaps keep us warm next winter.

Your comments are appreciated

Regards Mike. ;)

journeyman Mick
18th June 2005, 09:54 PM
Mike,
you may want to get the sparky to fit your 240v alarm at the same time as you get the wiring for your split system installed - save a bit on installation costs.

Mick

MICKYG
19th June 2005, 10:02 AM
Mick, I am doing my research to do three things, have the workshop protected with RCD device, fit up to power aircon, and fit 240V fire alarms. Thanks for your suggestion. This has come about by a little accident cutting off the power cord on a belt sander. The gpo's in the shed are not protected, and I have a 15amp
point which is for the welder. I have had no problems before and always believed the 15amp point was the only thing not protected in the shed. So a wake up call for me to investigate the matter and act accordingly. The sander was brand new
and would not have run for thirty seconds, it now sports a shortened cord.

A few changes are in the pipeline for the shed etc.

Regards Mike.