What diameter cable for these heaters please?

[JasonA]

Hi guys,

I'm going to be installing two infra-red electric heaters in a bedroom that will be run together off of one supply: One is 500W and the other is 600W, so I take it we deem that an 1100W load?

What diameter cable should I use: Research so far seems to suggest 1.0mm - is that correct?

I'd be grateful to know as it will affect which size of trunking I buy.

Many thanks in advance for any replies.

Jason.

 

[Spoon]

Welcome to the forum mate.

Is this being wired to a plug?

Just to add.  Minimum size for 'Power Circuit' is 1.5mm 

 

[Telectrix]

as above. need more info. are you asking what size flex for each heater, or fixed wiring? answers on a beermat. 

 

[JasonA]

Hi Spoon and Telectrix, 

Thanks so much for replying! Top blokes!

This is my first ever post on this forum. Funny, I have "notify me of replies" ticked, but it didn't tell me you'd replied: I came on here to check.

Here's what I was planning: It won't be wired into a plug, I was planning to "tap off" of another supply either by hard wiring into the back of an existing socket or from a supply to an existing heater. That would run straight into a fused switched spur, to switch on or off the supply to the heaters. Then the wire would run along the wall to the thermostat, then from the thermostat off to one heater, then continue on to the other heater. One is 500W, the other is 600W. Close to each heater would be another fused switched spur so they could be switched on and off individually if desired, rather than both at the same time, all the time (the heaters are pointing at different areas of the room). 

So, for the run from the supply to the thermostat and on to the heaters, I was wondering what size flex I need, as it will determine the size of trunking I buy.

Thanks again for your help, very kind.

Cheers,

Jason. 

 

[JasonA]

as above. need more info. are you asking what size flex for each heater, or fixed wiring? answers on a beermat. 

Welcome to the forum mate.

Is this being wired to a plug?

Just to add.  Minimum size for 'Power Circuit' is 1.5mm 

Hi Spoon and Telectrix, 

Thanks so much for replying! Top blokes!

This is my first ever post on this forum. Funny, I have "notify me of replies" ticked, but it didn't tell me you'd replied: I came on here to check.

Here's what I was planning: It won't be wired into a plug, I was planning to "tap off" of another supply either by hard wiring into the back of an existing socket or from a supply to an existing heater. That would run straight into a fused switched spur, to switch on or off the supply to the heaters. Then the wire would run along the wall to the thermostat, then from the thermostat off to one heater, then continue on to the other heater. One is 500W, the other is 600W. Close to each heater would be another fused switched spur so they could be switched on and off individually if desired, rather than both at the same time, all the time (the heaters are pointing at different areas of the room). 

So, for the run from the supply to the thermostat and on to the heaters, I was wondering what size flex I need, as it will determine the size of trunking I buy.

Thanks again for your help, very kind.

Cheers,

Jason. 

 

[Spoon]

What does the manual to the heaters say about installation?

 

[Telectrix]

TBH, judging by your posts, I don't think you have the knowledge and the equipment to ensure a safe installation. I'd consult a local spark.

 

[JasonA]

What does the manual to the heaters say about installation?

It doesn't go into much detail: It doesn't mention wire size.

TBH, judging by your posts, I don't think you have the knowledge and the equipment to ensure a safe installation. I'd consult a local spark.

I've fitted them twice before with no problems: They were much bigger heaters of a higher wattage, so I used 2.5mm T&E to be on the safe side. With these ones being much smaller and lower wattage, I'd like to use the smallest wire that's safe to use so it fits in smaller trunking for a neater-looking job.

 

[Telectrix]

OK. look at app.15 in BS7671. spur from ring final circuit. fuse down at socket that you're coming off, (13A), then a single 1.5 mm to heaters. D/P neon switch for each heater.

 

[JasonA]

OK. look at app.15 in BS7671. spur from ring final circuit. fuse down at socket that you're coming off, (13A), then a single 1.5 mm to heaters. D/P neon switch for each heater.

Right, brilliant, fully understood. Thank you very much Telectrix.

 

[binky]

just to add, as these will be pulling a load for long periods of time, I might be tempted to use a heat resistant flex for a bit of 'belt and braces'. Having said that lighting circuits can carry roughly 1,5kW on a 6A cct without melting anything, and we wire that in 1mm FTE. (fair to say it's not often all the lights are on at the same time).

 

[JasonA]

just to add, as these will be pulling a load for long periods of time, I might be tempted to use a heat resistant flex for a bit of 'belt and braces'. Having said that lighting circuits can carry roughly 1,5kW on a 6A cct without melting anything, and we wire that in 1mm FTE. (fair to say it's not often all the lights are on at the same time).

Thanks Binky, I'll definitely do that. I'm all for the "belt and braces" approach!

 

[Andy™]

Yes,  1.0mm diameter cable is correct one to use

cables are not measured by diameter... and if its part of the fixed wiring, if you mean 1mm², even that isnt compliant as per first post, min size is 1.5mm²