How much current can 1.0mm handle?

[amateurSparky]

I had an FCU fitted by my electrician. I'm connecting a burglar alarm to the FCU. I have a 3AMP fuse in it. Would 1.0mm be good enough? I do have some 1.5mm left but I thought I'd ask just in case I make an amateur mistake. Also tell me where it is in the regs because it's good practise for me since am training to be a domestic spark

Also is it true it's bad practice to mix high voltage cables and low voltage together? Due to how the fcu is positioned I will have a very long cable going across the entire width of the panel towards the terminal block on the right hand side with the zone wiring on top.

It looks ugly and unsafe but at the time I didn't give it a second thought since I just wanted to get it working.

 

[conny]

1.0mm is perfectly adequate for a 3A load.
By high voltage/low voltage what are you referring to?
Mains supply with telephone/computer cables in the same trunking or something similar?

Just re-read your post and realise what you mean.
Try to keep a gap of about 25mm(1") between the mains cable and zone cables and it should be alright. Do not bundle them close together.

 

[amateurSparky]

The zone wiring for the sensors are on top of the supply cable since like I said it runs across the entire width of the panel to get to the terminal block feeding the transformer.

 

[PrenticeBoyofDerry]

1.00mm T&E will carry a maximum 16A.
high voltage-low voltage?
or low voltage-extra low voltage?

 

[Alarm]

Ideally only cross at right angles and as little as possible and keep 25mm away from runs.

 

[conny]

If you have the space and enough slack can you raise the zone cables clear by supporting them on stand-off pillars?

 

[RF Lighting]

It of course depends on derating factors too though PboD

 

[riveralt]

I had an FCU fitted by my electrician. I'm connecting a burglar alarm to the FCU. I have a 3AMP fuse in it. Would 1.0mm be good enough? I do have some 1.5mm left but I thought I'd ask just in case I make an amateur mistake.

Assuming the FCU has been powered properly itself 1mm T&E is more than sufficient for alarm systems provided it does not go through insulation and even given what you are powering it still should not be an issue.

Also is it true it's bad practice to mix high voltage cables and low voltage together? Due to how the fcu is positioned I will have a very long cable going across the entire width of the panel towards the terminal block on the right hand side with the zone wiring on top.

You don't have high voltage cables in your house - at least I hope not - you have low voltage cables. If you mean cables of different current carrying capacity then, in the scenario you have described, there are no issues - fuses/MCB's etc should be rated for the minimum cable size - you FCU covers that. However long cable runs can cause voltage drop - but again from what you describe it should not be an issue.
As for your connection to the alarm, which is what I assume you are referring to - that connection should take place inside the alarm itself.

It looks ugly and unsafe but at the time I didn't give it a second thought since I just wanted to get it working.

Perhaps a photograph would assist in that assessment.

 

[PrenticeBoyofDerry]

It of course depends on derating factors too though PboD

I agree, like I said the maximum allowed is 16A.
But even with 50% de-rating it will still carry 8A safely.
and taking in to consideration the question was "How much current can 1.0mm handle?" I think I may have scored quite highly, even on BAS's score sheet
But now here comes shyt about multicore thermo, single core, mimms etc.....
amateurSparky
I would not be too happy having voltage bands 1&2 together, thought about segregation via trunking/conduit.

 

[ban-all-sheds]

How much current can 1.0mm handle?

About 72A.

Little exercise for you (nobody give the answer away, please):

Given the graph above, how did I arrive at about 72A?

 

[ban-all-sheds]

He's gone very quiet....

 

[Alarm]

Very, but as you "bumped" this.

in the scenario you have described, there are no issues

Is slightly wrong, alarm cables and mains should be kept as far apart as possible.