I want to run a new cable from my consumer unit to pick up 2 CO alarms and 4 smoke alarms:

Is a 1.5mm cable from a spare 16A MCB okay?
Does the cable need to run from alarm to alarm (i.e. radial) or can I run a single cable to the furthest one and spur off at 4 points for the other? (the later would use much less cable)
If I did the latter, would it cause problems?

"Cordless Crazy" wrote in message
...

I want to run a new cable from my consumer unit to pick up 2 CO alarms
and 4 smoke alarms:

Is a 1.5mm cable from a spare 16A MCB okay?
Does the cable need to run from alarm to alarm (i.e. radial) or can I
run a single cable to the furthest one and spur off at 4 points for the
other? (the later would use much less cable)
If I did the latter, would it cause problems?


--
Cordless Crazy

I think a 16A MCB is a bit high - 6A should do it. The alarms *must* all be
the same brand with a single T&E from the CU to the first one then 3-core&E
to the next and so on in a radial-type circuit. Have a look at:

http://www.tlc-direct.co.uk/Technica...idde/Index.htm

for installation instructions of Kidde alarms.

John.

I want to run a new cable from my consumer unit to pick up 2 CO alarms
and 4 smoke alarms:

Is a 1.5mm cable from a spare 16A MCB okay?

Yes.

Does the cable need to run from alarm to alarm (i.e. radial) or can I
run a single cable to the furthest one and spur off at 4 points for the
other? (the later would use much less cable)
If I did the latter, would it cause problems?

It is normal for the smoke alarms to need a 3&E interconnect. You normally
achieve this by running the main supply to the nearest alarm. The other
alarms are then connected to each other from the first one using the 3 core
cable (such as that intended for 2 way lighting circuits), which usually
consists of a live, neutral and signal core (plus the earth, of course). You
can run the cable in any manner that is convenient, whether star or daisy
chained. If the alarms genuinely use 2 cores of the interconnect as live and
neutral, then the initial (T&E) supply line can go straight to a star
topography junction box.

If the alarms are of different brands, then the interconnect probably won't
work/will destroy the alarms. You should take them back/discard them and buy
same branded linked alarms from a single manufacturer.

Christian.

Cordless Crazy wrote:
I want to run a new cable from my consumer unit to pick up 2 CO alarms
and 4 smoke alarms:

Is a 1.5mm cable from a spare 16A MCB okay?


Make it a 6A MCB and no problems, however 16A is a) far above what is
required for smoke alarms, and b) unlikely to be sufficient protection
for a 1.5mm circuit.

I think a 16A MCB is a bit high - 6A should do it.

Whoops. Yes, I didn't notice the oversized MCB.

Christian.