old imperial cables

[iamatinca]

has anybody got information ie current carrying capacities of old size single cables. the sizes are 7/0.029 which is near enough 3mmm,and 3/0.029 which is just over 1.25mm.these cables date back to the 1970 .the estate that i work on has these cables thru out. they are old, but when you pull them out for a rewire they are in mint codition also the insulation is twice as thick as present day t&e thanks in anticipation

 

[Andy™]

assuming clipped direct i think

1/.044 0.97mm2 12A

3/.029 1.29mm2 15A

3/.036 1.94mm2 19A

7/.029 2.90mm2 23A

7/.036 4.52mm2 31A

7/.044 6.45mm2 37A

7/.052 9.35mm2 46A

7/.064 14.52mm2 61A

19/.044 19.35mm2 63A

19/.052 25.81mm2 75A

19/.064 38.71mm2 101A

i should have a better version somewhere. ill see if i can find that

 

[Andy™]

from 15th i think

the original version is larger. if anyone wants it, pm me your email and ill get it to you

 

[iamatinca]

thanks a lot lads and so quick,very gratefull

 

[SPECIAL LOCATION]

Another link with a cable size comparison chart is..

http://www.voltimum.co.uk/files/gb/others/5/200701209767imperialcables.pdf

You could use next lowest size for current calc..

or larger size if puttin in new cable to extend circuit.

 

[Evans Electric]

If, as you say, they are in mint condition, one wonders why they need to be rewired. I presume there is no earth with the lighting but the 7/.029 stranded T/E for the plugs is equal to our 2.5 mm and as my earlier post , is a joy to work with unlike the solid strand carp inflicted on us at metrication.

Deke

 

[septiclecky]

from 15th i think

the original version is larger. if anyone wants it, pm me your email and ill get it to you

I served my time on the 14th edition in 1973 and cable sizing was metric then so it is definatly not 15th edition. Cable sizing went metric around 1970 so imperial size cables ended late 60's

.

 

[septiclecky]

If, as you say, they are in mint condition, one wonders why they need to be rewired. I presume there is no earth with the lighting but the 7/.029 stranded T/E for the plugs is equal to our 2.5 mm and as my earlier post , is a joy to work with unlike the solid strand carp inflicted on us at metrication.Deke

You can buy stranded 1.5 & 2.5 T & E as well as singles but no one will pay the extra cost for it.

 

[SPECIAL LOCATION]

I served my time on the 14th edition in 1973 and cable sizing was metric then so it is definatly not 15th edition. Cable sizing went metric around 1970 so imperial size cables ended late 60's.

yep... The back section of Approved Doc' P suggests imperial cables could still be purchased up until beginning of the 1970's!

also mentioned some copper imperial cables were tinned copper,

 

[Andy™]

I served my time on the 14th edition in 1973 and cable sizing was metric then so it is definatly not 15th edition. Cable sizing went metric around 1970 so imperial size cables ended late 60's.

older than i thought then. 13th maybe? or even 12th?

 

[SPECIAL LOCATION]

older than i thought then. 13th maybe? or even 12th?

could always check the good book......Blushing

Pg 7 the big red book... Editions...

14th Edition: 1966;

reprints & amendments:- 1968,1969,1970,1972,1973,1974,1976

{ 1970 amendment includes incorporating 'Metric' units! }

15th Edition: 1981.

so it would appear to be pre 1970 14th ed' & earlier regs with Imperial stuff.

 

[iamatinca]

this estate of about 1200 properties was finished in 1980,the ring mains are 7/0.029 including the cpc.the light circuits are 3/0.029 including cpc.the earth conductor is 7/0.052 =9.4mm and the main bond is 7/0.044=6.5mm, all run in plastic conduit.the main reason for the rewires is building movement chopping the conductors also the occasional conduit full of water(water leaks) attacking the insulation.

 

[Evans Electric]

There were two 14th editions if I remember correctly, after we all shelled out for the 14th ,they issued the 14th edition ( Metric) . I can't pinpoint the year . Steel conduit changed from 3/4" to 20mm , 2 X 2 trunking became 50 X 50mm , Switchplate screws went from 4BA to M3.5 ,conduit box screws were 2BA now M4. And we started to measure in metres from yards, feet and inches. Pyro (Micc) sizes became simpler as I remember.

Deke

 

[Evans Electric]

You can buy stranded 1.5 & 2.5 T & E as well as singles but no one will pay the extra cost for it.

Not many people know that,thanks Septic , interesting, I'll ask how much it is.

Deke

 

[SPECIAL LOCATION]

There were two 14th editions if I remember correctly, after we all shelled out for the 14th ,they issued the 14th edition ( Metric) . I can't pinpoint the year . Steel conduit changed from 3/4" to 20mm , 2 X 2 trunking became 50 X 50mm , Switchplate screws went from 4BA to M3.5 ,conduit box screws were 2BA now M4. And we started to measure in metres from yards, feet and inches. Pyro (Micc) sizes became simpler as I remember. Deke

Erm get your glasses outa yer handbag sandra..

look back at post #11!!!

Pg 7 the big red book... Editions...14th Edition: 1966;

reprints & amendments:- 1968,1969,1970,1972,1973,1974,1976

{ 1970 amendment includes incorporating 'Metric' units! }

15th Edition: 1981.

 

[Evans Electric]

Erm get your glasses outa yer handbag sandra..look back at post #11!!!

Sorry Specs, but I started with the 13th and get forgetful these days. Anyway those glasses clash with my nail varnish !! Blushing

Sandra