The rubbish some people consider suitable

[SUNRAY]

At the weekend I was working at an event, customer had stated mains power was available at the location I was to be working.

On the day he provided an extension lead: "There you go, it plugs in over there."

He didn't understand why I opted to use my own.

 

[ericmark]

I note BS 7671 since 2008 has stipulated the size of lead to connect a caravan as 2.5 mm² and 25 meters long, but walk into most caravan shops and 1.5 mm² is offered in varying lengths.

It also stipulates core colours, but try buying yellow artic lead with brown, grey and green/yellow cores. We know it should not be blue as there is no neutral, and we know yellow means 110 volt, so why is cable with brown and blue cores offered for sale?

Same with plugs and sockets marked L and N instead of L1 and L2. But what are the chances complaining on this forum will mean correctly marked cables, plugs, and sockets are offered for sale?

 

[SUNRAY]

I note BS 7671 since 2008 has stipulated the size of lead to connect a caravan as 2.5 mm² and 25 meters long, but walk into most caravan shops and 1.5 mm² is offered in varying lengths.

I can never quite understand why that has been so strictly specified. So often it only needs to be several metres. My sister/nephew used to have a camper van and they kept finding they had to get another cable to comply with the rules of countries/sites

It also stipulates core colours, but try buying yellow artic lead with brown, grey and green/yellow cores. We know it should not be blue as there is no neutral, and we know yellow means 110 volt, so why is cable with brown and blue cores offered for sale?

Same with plugs and sockets marked L and N instead of L1 and L2. But what are the chances complaining on this forum will mean correctly marked cables, plugs, and sockets are offered for sale?

That piece of cable is about 2.5mm² and red, black. green cores so 50 years old.

 

[securespark]

I would have told him it was a hazard!

Think the flooring and the lead are a similar vintage...

I have a camping lead with orange sheath which is 25m and 2.5.

 

[SUNRAY]

I would have told him it was a hazard!

I did and he eventually accepted it when I simply pulled a chunk off, to the point he accepted my offer to repair.

Think the flooring and the lead are a similar vintage...

it is... in fact the floor is the $@*% Mrs Sunray wouldn't let me rip out when we made major changes to our kitchen

I have a camping lead with orange sheath which is 25m and 2.5.

I have significant quantities of similar sorts of leads ranging from 1m to 100m with 16A & 32A connectors. My stock used to be circa 2Km but I reckon 25% of that now as I don't really get involved with site temporaries at 68. However very little ever of orange.

 

[JohnW2]

I note BS 7671 since 2008 has stipulated the size of lead to connect a caravan as 2.5 mm² and 25 meters long.... It also stipulates core colours, but try buying yellow artic lead with brown, grey and green/yellow cores. We know it should not be blue as there is no neutral, and we know yellow means 110 volt, so why is cable with brown and blue cores offered for sale?

I'm not sure I understand much of that that. What's all this about 'yellow', 110V and 'no neutral)?

BS7671 does, indeed, say a minimum of 2,5mm² and a maximum of 25 metres, but it also says a maximum of 230V (or 400V 3-phase), and says absolutely nothing about 'yellow'. As for 'core colours' it merely refers one to Table 51, which gives the standard colurs we are used to,and the diagram of connections to a caravan refer only to a "Neutral", identified with blue. ...

I'm clearly missing something - can you help me understand?

Kind Regards, John

 

[SUNRAY]

I can never quite understand why that has been so strictly specified. So often it only needs to be several metres. My sister/nephew used to have a camper van and they kept finding they had to get another cable to comply with the rules of countries/sites

But he carries a SY, a black HO7 and orange HO5 in 2.5mm² all correctly marked, I would have thought one of those should have been acceptable.
Plus he carries 4mm² blue arctic and the 1.5mm² yellow that he uses at home and a selection of different adapter leads.

Hopefully he won't need any more.

 

[Risteard]

I'm not sure I understand much of that that. What's all this about 'yellow', 110V and 'no neutral)?

BS7671 does, indeed, say a minimum of 2,5mm² and a maximum of 25 metres, but it also says a maximum of 230V (or 400V 3-phase), and says absolutely nothing about 'yellow'. As for 'core colours' it merely refers one to Table 51, which gives the standard colurs we are used to,and the diagram of connections to a caravan refer only to a "Neutral", identified with blue. ...

View attachment 315065

I'm clearly missing something - can you help me understand?

Kind Regards, John

Both live conductors is an RLV system are phase conductors. There is no neutral on the secondary side.

 

[JohnW2]

Both live conductors is an RLV system are phase conductors. There is no neutral on the secondary side.

I have no idea what an "RLV system" is.

"Secondary side" of what?

What you say is obviously true of an isolated and non-earth-referenced supply (i.e. "SL:V"), but why do you think that's what we are talking about?

As I said and illustrated, BS7671 talks about the Neutral in the supply to the caravan (identified by blue colour), shows a CPC in the cable and requires the supply to be RCD protected, so doesnt't seem to be talking about a non-earth-referenced isolated aupply.

Hopefully eric will clarify what he meant.

 

[Risteard]

I have no idea what an "RLV system" is.

"Secondary side" of what?

What you say is obviously true of an isolated and non-earth-referenced supply (i.e. "SL:V"), but why do you think that's what we are talking about?

As I said and illustrated, BS7671 talks about the Neutral in the supply to the caravan (identified by blue colour), shows a CPC in the cable and requires the supply to be RCD protected, so doesnt't seem to be talking about a non-earth-referenced isolated aupply.

Hopefully eric will clarify what he meant.

Reduced Low Voltage. The secondary of the transformer.

 

[ebee]

I am not entirely sure why RLV crept in on this one.
It`s pretty much a UK thing and requires a transformer to cut it down to 110v centre tapped and the centre tap being 63.5V max if derived from a 3 phase supply.

But I thought the conversation was about the usual single phase 240V AC supply with Line/Neutral/Earth (OK call it 230V if you want to)

 

[ericmark]

My point was with a split phase supply with most 110 volt supplies are, where there is no neutral conductor, which most 110 volt supplies don't have a neutral conductor supply is phase to phase, there should be no blue wires or terminals marked N. I know there is 63 or 55 volt to earth, but unlike 230 volt supplies with PEN conductors we never use the earth, not really an option as one would not know if 55 volt (from single phase supply) or 63 volt (from 3 phase supply) there is simply no neutral.

However we all know in the real world 110 volt plugs and cable normally does use N and blue even though because the outer of the cable, plug or socket is yellow so should never be used with 230 volt supplies.

It works and in the main that is all people want, so the question is how far can we stray from what we should do, I know around where I work there are blue 16 amp outlets, no idea what they were fitted for, so may have been fully compliant for there intended use, however the site has a TN-C-S supply, so they should not in theroy be used for caravans, motor homes, or any other item which has a metal outer shell earthed to the supply, however all the buildings are steel girder constructed and they are bonded to the railway lines, so it is highly unlikely with a loss of PEN with 8 mile of railway track that the metal will raise more that a couple of volts from true earth value.

So should anyone really worry about the sockets being used for caravans or butty vans? Technically not permitted, but in the real world not really a problem.

So the big question is if the site where @SUNRAY was working was supplying a safe supply for @SUNRAY to use, not a clue what he was plugging in, did it need an earth, clearly using class II equipment is not a problem, if using class I equipment was the earth good enough for the equipment being used?

I had the same a couple of weeks ago at a gala, on car park duty and a steam organ arrived and the normal place it went was already occupied, I was left to work out what to do, I knew it needed power, so directed it to where it could get power telling the people they could unplug the caravan and plug their organ in instead, I have no idea if the supply was TT, TN-S or TN-C-S likely the latter, I was a car park attendant on that day, and had enough problems without dealing with a steam organ. Which runs on air not steam so no idea why called a steam organ.

My biggest problem was no one wanted the organ next to their gazebo, it's great for visitors, but being next to it all day, that's some thing else, darn thing not even in tune. So I am looking at it from the customers side, the guy was likely under pressure, and not an electrician, and possibly if like me had nothing or little to do we the pre event organisation. So was getting along as best as he could in a stressful situation and likely grateful that @SUNRAY took away some of the pressure of the day.

 

[Harry Bloomfield]

I note BS 7671 since 2008 has stipulated the size of lead to connect a caravan as 2.5 mm² and 25 meters long, but walk into most caravan shops and 1.5 mm² is offered in varying lengths.

I have never come across the 1.5mm.

 

[Harry Bloomfield]

That piece of cable is about 2.5mm² and red, black. green cores so 50 years old.

Where is your sense of adventure

 

[SUNRAY]

I note BS 7671 since 2008 has stipulated the size of lead to connect a caravan as 2.5 mm² and 25 meters long, but walk into most caravan shops and 1.5 mm² is offered in varying lengths.

I have never come across the 1.5mm.

Oh yes I concur the various caravanning outlets offer differing hook-up cables. Just before covid I required a cable in a hurry for an event and all the nearest caravan outlet had was 15m 1.5mm² in blue and the cable only had 3g1.5mm written on it, no BS number, maker etc.