Old cable data sheets.

[Lucien Nunes]

Nice! Sitting on a DAC90 unless I'm mistaken.

 

[freddo]

Nice! Sitting on a DAC90 unless I'm mistaken.

Well spotted!

 

[pc1966]

Resistance of 125mm² lead = 2.2E-7 / 125E-6 = 1.76mΩ/m
Resistance of 151mm² lead = 2.2E-7 / 151E-6 = 1.46mΩ/m
Resistance of 19/.064 TC = 0.4195Ω / 1000 yds. = 0.459mΩ/m

Comparing that to 2-core 35mm SWA which looks closes today I see R1 as 0.524 mOhm/m and the armour R2 as 2.6mOhm/m, so the lead sheathed cable is better!

For a given definition based on Zs (or more specifically R2/R1 as about 5 for SWA and about 3.8 for old stuff) and using the Prysmian data sheet for BS5467 cable

 

[Lucien Nunes]

The Enfield cable has a thinner sheath so might be closer to SWA. Obviously some PILC has wire armour in parallel, some has tape which is less beneficial as a CPC.

Hopefully the OP will be able to confirm the larger cable data and if I go to the warehouse tomorrow I will have a look for 1960s data books.

In the meantime, while we're doing electrical-industry-promotional-items-on-radios here's a pocket electrical slide-rule from Hackbridge and Hewittic (the transformer and rectifier people)

 

[freddo]

That looks in nice clean condition! Sat on a Pye MM?

 

[Lucien Nunes]

Yes, one of the MMs that won't be working any time soon due to disintegrated Mazak castings in the tuning gang.

 

[freddo]

A friend had one, the mazak was also in a terrible state and crumbling, the moving parts seized.

 

[Gnasher]

Let's try to validate the lead CSA for the older BIC 19/.064 by calculating it both from the stated dimensions and from the linear weights.

Lead O/D = 0.85 ins. = 21.59mm
Lead I/D = 0.85 - (2 * 0.08) = 0.69 ins. = 17.53mm
Lead CSA from dims = ((21.59 / 2)² - (17.53 / 2)²) * Π = 125mm²

Weight of twin cable = 43.75cwt / 1000 yds. = 2.431kg/m
Weight of 19/.064 copper = 720.3 lbs / 1000 yds. = 0.3573kg/m
Weight of lead (ignoring paper) = 2.431 - (2 * 0.3573) = 1.7164kg/m
Lead density (ignoring alloying elements) = 11.34g/cm³
Lead volume per metre = 1716.4 / 11.34 = 151.4cm³
Lead CSA from weight = 151mm²

Lead resistivity 2.2E-7 Ωm @ 20°C ignoring alloying.
Resistance of 125mm² lead = 2.2E-7 / 125E-6 = 1.76mΩ/m
Resistance of 151mm² lead = 2.2E-7 / 151E-6 = 1.46mΩ/m
Resistance of 19/.064 TC = 0.4195Ω / 1000 yds. = 0.459mΩ/m

I'll do the later Enfield cable in the morning unless someone wants to save me the effort.

Lucian

This brilliant. I cant believe you have gone to this amount of effort to help.

Perhaps the best way would take an average of the 125mm² and the 151mm². That's probably a reasonable assumption.

You did mention the lack of 19/.103, this should be 19/153.

if you could assist with the larger cable that would be much appreciated.

Steve

 

[Lucien Nunes]

Feel free to mash the winner button if you like the service!

I didn't get round to the later Enfield 19/.064 cable yet, that is more likely to be of similar construction to your 1960s cable as they were probably both made to the later British Standard. The lead is significantly thinner so we should calculate that before making a final call on the sheath resistance.

Re the larger cable, I can't make sense of the '19/153' or '19/1.53' as given earlier.

• 19/1.53 is a valid metric cable stranding for 35mm²
• Trying to read it as an imperial size '19/.153' would make it 225mm²
• My reference to 19/.103 was a top-of head attempt to match it to your comment that it was 95mm² equivalent. 19/.103 did exist as a stranding and is just over 95mm², but does not seem to have been used as a core of PILC.
• 95mm² equivalent imperial size as a PILC core invariably seems to have been 37/.072

So we really need to clarify that number and gather any other possible information before we can make headway with the larger cable.

 

[Old Tiler 177972]

Hello, I've just located this forum as I'm trying to acertain the weight of old BICC cables and Google brought me here. Some of the images and info above have been most useful, however there are other questions I still have.

I've seen that the chap who posted a lot of the info has sadly passed away, does someone have access to the BICC "Cables & Tables" books please?