FAO Mr. WM

[penance]

Hiya mate

As you know im going to be doing a dedicated mains supply soon, I was wondering if theres anything in this cable cyro treatment.
Ill be useing 4mm2 3 core SWA, is there any point in haveing the cable treated or is it not a worthwhile idea, and if it is whats a guestimate cost?

 

[Robbo]

Personally, I think this could be a very bad idea. What happens to the plastic insulation during the cryo process? If it becomes brittle and cracks, you could have a very nasty electrical situation developing

 

[penance]

oh yea
i forgot to ask the effect of the treatment on the cable insulation

 

[wadia-miester]

Penance, we 'prefer' to treat the cables before covering, (a lot of companies don't) does make it difficult.
Our view is that with different materials, not just the main cable compostion, but diaelectrics/sheathing and outer casing all have different 'genetic make up's ' if you like, for example PVC (a coomon cable constructional component) has a safe lower limit of -20 C (-60 on artic cable), some what lower that the -190 degrees C that most cryo baths go, is the grain structure 'relaxing points' the same of PVC say as for gold or silver/copper or PTFE?, and what happens when you drop them down together, is the effect imediate?, does it happen at all?, can it degregate over a period of Time?
Intrestingly, most areospace cyro treatments are around the minus 55 degrees range
To be honest, I can't say it isn't or it is , if it were an i/c or speaker wire, then it's no biggy to change it, but interior wall mains wire, now thats a different cookie.
Cryo treating does work, no problemo, however the application is the key. WM

 

[rewster]

-55, Surely that's for choc ice's only!:ffrc: