EHU cable thickness

acropolis22

acropolis22

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The cable I have is 2.5 mm2 cores, allegedly. If my memory serves me right, that would be enough for 30 amps current? The connectors are described as 16 amp.

Is this cable over the top? I ask because it's really thick and stiff, (ooer missus), and a real pain to stow away. Could I buy a lower rated cable that would be thinner and easier to handle, given that most site supplies seem to be rated at 16 amps or less?
 
2.5mm is recommended however, as you say, a lower gauge may suffice however, would suggest you get a more flexible 2.5mm, eg Arctic.
 
1.5mm is rated at 15amps so could be used, 2.5mm is rated at 20amp gives you some wiggle room.
 
I’d personally prefer the thicker, especially if you may need to put it where it may get driven over.
 
If weight is a problem, get a thinner and shorter cable.
For flexibility, get Arctic cable. Arctic may not be so easy to find.
They are usually yellow or blue and much more flexible than the standard (stiff) variety.

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I have a 2.5 cable which I would use for long runs , 1.5 is better for short runs ,
 
I suspect we could have much thinner lighter cable. The most we have on would be a water heater and possibly a 2 kw fan heater. We have no other electrical appliances with a significant load.
 
If you're going to run a heater, I'd go for 2.5mm2 cable. You cannot be sure that things won't come on together and 2kW is quite a bit. I think the rated limit for 1.5mm2 cable is 10A, so it's cutting it a bit fine.
 
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1.5mm Bs6094 arctic cable like the below is rated at 16A



25m 1.5mm 3 Core Arctic Blue Flex Cable 3183AG 16 AMP Rated BS6004 BASEC Approved Outdoor Cable Hookup Leads Amazon product ASIN B075F7PZNG


You could save a few quid and buy a coil and use your existing plug and socket.

The same supplier also has it in yellow (usually used for 110v) and 2.5mm blue Arctic too.

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two said:
If you're going to run a heater, I'd go for 2.5mm2 cable. You cannot be sure that things won't come on together and 2kW is quite a bit. I think the rated limit for 1.5mm2 cable is 10A, so it's cutting it a bit fine.
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2kw is only 8A, so a 10A rated cable would be fine. Not many campsites give you more than a 10A breaker anyway, so it would trip out before your cable melts! But remember to completely unroll the cable before use!
 
Another consideration is voltage drop. Over a 50m length (25m there and back) the voltage drop at 16 amps is 5V for a 2.5mm2 cable, and 9V for a 1.5mm cable. That's 2% and 4%. The usual criterion for acceptable voltage drop is 3%, but you may choose to accept more than that. You'll notice that outside the UK, 1.5mm2 is common.

I have a 25m and 10m length of 2.5mm2 cable. I find that about 80% of the time I can use the 10m.

Arctic grade cable is flexible at low temperatures. You can find it in both blue and yellow. The idea is that the colour code blue is for standard 240V, and yellow is for 110V dual-live supplies as found on building sites. The cable construction is the same, and there is a possible advantage that yellow is more visible in grass than blue. If you are making your own cable with blue plug and socket, make sure the connection is tight - it's regularly reported on here that plugs and sockets get hot and fail due to a bad wire connection.
 
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The size of a cable should be governed by the supply, and it's associated protection, not the load. If you have a 16A plug on it the cable must be rated at 16A at the very least. 1.5mm2 cable with a 16A rating is the least that you can use within the regulations.
The recommendation for 2.5mm2 is to reduce voltage drop but also has more resistance to being run over by vehicles.
I'd stick with 2.5 mm2 arctic cable IMO.
 
Just a note to consider I’ve been on some sites that state the ehu cable has to be orange.
Can’t really see why but yellow or orange would be better than a dark colour.
Makes my other half laugh when I go on about the state of some people’s bird nest of a hook up cable.
I carry one 10m and one 25m cable both 2.5mm orange.
As stated by others bigger gauge cable less voltage drop less chance of burning the cable.
Just make sure it’s fully unwound.
Cable reals have been banned on a lot of building sites due to the fire risk.

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A 20m run with 1,5mm2 cable and 3kw load, will have a loss of 3,15% from a 230v supply, or 7,25v drop. Very acceptable. If you think going beyond 20m long, then go 2,5mm, otherwise I see no benefit since the largest hook up will be limited to 16a or 3,8kw.
 
acropolis22 said:
The cable I have is 2.5 mm2 cores, allegedly. If my memory serves me right, that would be enough for 30 amps current? The connectors are described as 16 amp.

Is this cable over the top? I ask because it's really thick and stiff, (ooer missus), and a real pain to stow away. Could I buy a lower rated cable that would be thinner and easier to handle, given that most site supplies seem to be rated at 16 amps or less?
Click to expand...
I hope not 2 core! It must also have an earth cable!
 
Off da Grid said:
Just a note to consider I’ve been on some sites that state the ehu cable has to be orange.
Can’t really see why but yellow or orange would be better than a dark colour.
Click to expand...
Less likely to drive a lawnmower over it, I think. It's a Brit thing, no-one else cares.
 
Abacist said:
I hope not 2 core! It must also have an earth cable!
Click to expand...
nobody said 2 cores. the post said 2.5mm2 cores,, meaning 2.5
images.png
cross section.
 
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I have a 25m 1.5mm sq yellow artic cable & a 15 m 1.5mm sq black cable, never draw anything like the full capacity of the cable as most continental sites are either 6 or 10 amp max anyway.

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autorouter said:
Less likely to drive a lawnmower over it, I think. It's a Brit thing, no-one else cares.
Click to expand...
I wouldn't want someone to drive over my cable and blow the fuse and then have to source another cable (or trip over it like me).
 
Off da Grid said:
Just a note to consider I’ve been on some sites that state the ehu cable has to be orange.
Can’t really see why but yellow or orange would be better than a dark colour.
Makes my other half laugh when I go on about the state of some people’s bird nest of a hook up cable.
I carry one 10m and one 25m cable both 2.5mm orange.
As stated by others bigger gauge cable less voltage drop less chance of burning the cable.
Just make sure it’s fully unwound.
Cable reals have been banned on a lot of building sites due to the fire risk.
Click to expand...
with only pulling a max of 16a via a 2.5 cable is the unreeling of a electric cable really necessary? Not saying it isn't just a question. Is it that some try and draw more than the 16a or more likely 8a supply that it then is a potential issue. I can see building sites have an issue with multiple sockets on the same reel and then connect 4 x Kango hammers to it. In the summer with no heating I rarely unwind my 2.5 cable - is that a potential issue?
I have seen some photos of burnt out cables but is that because of irresponsible use ie bit like putting a 20 x 13 amp extension on one socket at home and them connecting 20 heavy load appliances to it.
 
Bought this yesterday, thought the warning that is given on the packaging makes it not fit for purpose, well not with our climate :giggle: :beerchug:
1624604123591.png
 
pandas said:
with only pulling a max of 16a via a 2.5 cable is the unreeling of a electric cable really necessary? Not saying it isn't just a question. Is it that some try and draw more than the 16a or more likely 8a supply that it then is a potential issue. I can see building sites have an issue with multiple sockets on the same reel and then connect 4 x Kango hammers to it. In the summer with no heating I rarely unwind my 2.5 cable - is that a potential issue?
I have seen some photos of burnt out cables but is that because of irresponsible use ie bit like putting a 20 x 13 amp extension on one socket at home and them connecting 20 heavy load appliances to it.
Click to expand...
I don't know about 2.5 mm cable but 1.25mm cable (13amp) max current when cooled is 5 amps. So using the same logic the max on 2.5 mm would be 7.5 amps.
 
acropolis22 said:
The cable I have is 2.5 mm 2 cores, allegedly. If my memory serves me right, that would be enough for 30 amps current? The connectors are described as 16 amp.

Is this cable over the top? I ask because it's really thick and stiff, (ooer missus), and a real pain to stow away. Could I buy a lower rated cable that would be thinner and easier to handle, given that most site supplies seem to be rated at 16 amps or less?
Click to expand...
It is essential that you have a 3 core cable, a 2 core cable gives you NO earth fault protection

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pandas said:
with only pulling a max of 16a via a 2.5 cable is the unreeling of a electric cable really necessary? Not saying it isn't just a question. Is it that some try and draw more than the 16a or more likely 8a supply that it then is a potential issue. I can see building sites have an issue with multiple sockets on the same reel and then connect 4 x Kango hammers to it. In the summer with no heating I rarely unwind my 2.5 cable - is that a potential issue?, YES, the cable acts as a magnetic coil, inducing heats
I have seen some photos of burnt out cables but is that because of irresponsible use ie bit like putting a 20 x 13 amp extension on one socket at home and them connecting 20 heavy load appliances to it.
Click to expand...
 
bigalw35 said:
It is essential that you have a 3 core cable, a 2 core cable gives you NO earth fault protection
Click to expand...
You misread my post. It said mm2, as in sq mm. Agree that if I was using 2 core cable I would have no earth protection. I should have worded it differently.
 
acropolis22 said:
The cable I have is 2.5 mm2 (mm2, if you now saying is 2mm square, there is NO 2mm cable manufactured cores) allegedly. If my memory serves me right, that would be enough for 30 amps current? The connectors are described as 16 amp.
Click to expand...
The cable I have is 2.5 mm2 (mm2, if you now saying is 2mm square, there is NO 2mm cable manufactured)
You misread my post. It said mm2, as in sq mm. Agree that if I was using 2 core cable I would have no earth protection. I should have worded it differently.
 
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bigalw35 said:
The cable I have is 2.5 mm2 (mm2, if you now saying is 2mm square, there is NO 2mm cable manufactured)
You misread my post. It said mm2, as in sq mm. Agree that if I was using 2 core cable I would have no earth protection. I should have worded it differently.
Click to expand...
I honestly have no idea what you are talking about. The cable is 2.5 square mm. I can't make it any clearer. mm2 is often used as an abbreviation for square mm. I've never mentioned 2mm cable.
 
bigalw35 said:
if you now saying is 2mm square,
Click to expand...
You are right noboy uses square cable.

Jim, if you are reading this, can we have BBcode for superscript and subscript, please?

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