The use of "Arctic' cable

[ericmark]

Winter 09 of wiring matters has some clarification on BS 7919 and BS 6500 flexible cable.

It is documented that BS 7919 is for 55 - 0 - 55 volt use but I then when to Here H07BN4-F and here H07RNF on Eland Cables web site and I note rating of 450/750 volts.

But the article refers to 300/500V and to me it has not clarified but actually made it even more confusing. The 3183YAG does bring up Arctic flex with a 300/500V label but not BS 7919.

Batt Cables however list the BS 6500 cable as 300/500V and lists that as Arctic cable able to be used a -20deg C.

I am totally confused now at what cable should be used for what?

 

[ban-all-sheds]

some clarification

An interesting choice of words....

It is documented that BS 7919 is for 55 - 0 - 55 volt use but I then when to Here H07BN4-F and here H07RNF on Eland Cables web site and I note rating of 450/750 volts.

And 450/750V is indeed what BS 7919 covers, as it says in the article.

Remember at all times that it was written by Mark Coles, but the point he was making is that mechanically the cable has no special properties, it's just ordinary duty, and so wouldn't be safe to use at LV in harsh environments. I can see what he's getting at, but it seems bizarre to say that it's OK for a cable to be at risk of physical damage as it's only ELV.

But the article refers to 300/500V and to me it has not clarified but actually made it even more confusing. The 3183YAG does bring up Arctic flex with a 300/500V label but not BS 7919.

It won't as BS 7919 specifies 450/750V.

300/500 is the voltage rating for BS 6500 cable, which is normal PVC flex like wot everyone has in their home.

"Arctic" doesn't mean anything, in that it's not an official term, it implies no recognised performance standards, and its use is uncontrolled.

Batt Cables however list the BS 6500 cable as 300/500V and lists that as Arctic cable able to be used a -20deg C.

As the term is uncontrolled, it can be applied to any cable which a manufacturer believes is suitable for use in whatever conditions they mean by it.

I've not read BS 6500, but I'll bet it requires that the cables remain flexible to -5°C, not that it forbids them remaining flexible at less than -5°C.

So if BATT make a cable which ticks all the boxes for BS 6500 but exceeds its low temperature requirement, they can say it's OK for use down to -20°C and label it "Arctic" if they want.

I am totally confused now at what cable should be used for what?

The cable should have electrical properties (voltage rating and CCC) appropriate for its use, and mechanical properties appropriate for the external influences to which it will be subjected.

Seemples.


It may be that a BS or EN standard covers everything, or you may find that the standard(s) only cover part of your requirements and you have to look for cables which have enhanced performance in other areas, as testified to by the makers. As long as you stick to reputable makes you should be OK.

 

[ericmark]

I of course agree with what you say.
The point is on caravan sites and marinas the proprietor is responsible for general safety and he should not permit the use of unsuitable cables outside the tenants van or boat.

Since he has ability to check he should insure no under size or wrong types are used. Often one can find BS6500 or BS7919 marked on cable and also 1.5mm or 2.5mm but to then have to find manufactures name and check on there web site to me is unreasonable and unless some one can "Clarify" if all BS6500 or BS7919 should not be used on 230vac or under 5degC then the whole exercise is pointless.

Since I have found manufactures of both BS6500 and BS7919 which are rated at 450/750V I can't consider either as automatic failure. Also I have found both with different manufactures listed with temperatures below -20degC so to inspect cables to see is BS6500 or BS7919 is just pointless exercise.
Both 2.5mm and 1.5mm are good for 16A but figure Fig 708 says it should be 2.5mm and BS7919.

The chart in wiring matters clearly states BS7919 for 110 and BS6500 for 230 volt which looking at web sites seems to be wrong way around?

 

[holmslaw]

..

 

[Spark123]

Remember at all times that it was written by Mark Coles, but the point he was making is that mechanically the cable has no special properties, it's just ordinary duty, and so wouldn't be safe to use at LV in harsh environments. I can see what he's getting at, but it seems bizarre to say that it's OK for a cable to be at risk of physical damage as it's only ELV.

I don't think 110v CTE is classed as ELV, but I haven't read Mark Coles document for a while so am maybe getting the wrong end of the stick.

 

[ericmark]

I don't think 110v CTE is classed as ELV, but I haven't read Mark Coles document for a while so am maybe getting the wrong end of the stick.

55-0-55vac is considered as reduced low voltage but what is being said is 300/500 cable can't be used with a 230/400 volt ac supply as the peak voltage is 325/565 and that cable rated 450/750 is required which seems fair enough.

But the article says BS7919 is for 110 only and BS6500 is for 230vac but the manufactures web sites say BS7919 is 450/750v cable and BS6500 is 300/500v cable.

Cables to BS 7919
Electric cables - Flexible cables rated up to 450/750 V, for use with appliances and equipment intended for industrial and similar environments
Ordinary duty low temperate PVC insulated and sheath 300/500 V flexible cable, manufactured to BS 7919 Table 44 (not harmonised), commonly referred to as 3183A (Arctic Grade Flex), was specifically designed and, hence, included in the British Standard, for use at 110 Vac from centre tapped transformers (55V - 0 - 55V). The cable is suitable for installation and handling down to a temperature of -25°C, e.g. suitable for construction site installations and is often seen in use on temporary road works for supplies to traffic lights; Table 7B from BS 7450, refers. Note that cables to BS 7919 Table 44 have not been harmonised to European HDs. This is because the use of 110 V a.c. supplies from centre tapped transformers (55 V - 0 - 55 V) is a UK only practice and is not recognised or practised elsewhere.

One minute it is 450/750V next it is 300/500V I would have thought the IET would vet what they publish but it seems the proof readers have completely messed up here.

 

[Spark123]

Is flat twin and earth not 300/500v (BS6004)?

 

[ericmark]

Spark123 you are correct it seems 624-B LSZH from ELAND Cables and 624Y Twin & Earth PVC Cable BS6004 A05VVH4-U Batt Cables are both listed as 300/500V.

Does that mean any house wired in twin and earth should fail? Guardian Ali-Tube/LSZH Cable BS8436 is 600/1000V so it seems twin and earth is out?

 

[Spark123]

It means we use the RMS or nominal value when selecting cables

 

[ericmark]

That means Mark Coles must be right up the creak with his suggestions.

Oh what a surprise

 

[ban-all-sheds]

I don't think 110v CTE is classed as ELV, but I haven't read Mark Coles document for a while so am maybe getting the wrong end of the stick.

No - it's me being wrong.

But the article says BS7919 is for 110 only

Not exactly.

That means Mark Coles must be right up the creak with his suggestions.

Oh what a surprise

He might be, but I think that what he was saying in his article is that although BS 7919 cable is rated at 450/750V, it has no special mechanical properties, and therefore cannot be used in harsh environments because it is too easily damaged, BUT as the consequences of damage when it's used for a CTE 110V supply are not particularly dangerous it is OK to use it in harsh environments then.

That would make sense of the article, even if it seems a dubious assertion - I wouldn't fancy getting between 110V even if it was referenced to earth in the middle.