mineral insulated cable repair

[trev]

used to love doing micc, but i'm just weird!

You're not weird Kath, I love using it too

Last time I looked, you can bury the plastic coated stuff with all the usual tapes, depth, etc.

I stand corrected then, I still wouldn't though. I always though burying it was a regulation no no not just a Trev no no

 

[Guest55]

buried pyro is more common than you think trev , and perfectly acceptable as far as bs7671 is concerned.
in fact im on a commercial council job at the mo and theres a whopping 3/4" micc feeding a remote building , dont even wanna sneeze near it tho lol.

 

[snowhead]

Repair sleeve;

http://ro-ro.thermal.pentair.com/as...tion Instruction/4144/CDE-0925 Rev 0-1_06.pdf

Imperial to metric sizes; won't open in firefox needs I.E or ?

http://www.pyrosales.com.au/files/g...81&PHPSESSID=e2ecadaf1ac1e6bde53d01f9f408d475

 

[Adam W]

I always thought MI was a cable the regs did permit to be buried without additional protection - I've seen it done a few times.
If it's buried in the garden and the customer has dug though it I might be a little concerned about moisture getting in...

 

[trev]

As I say, I stand corrected but copper it's staying a no no as far as I'm concerned

 

[Thefailsafe2012]

used to love doing micc, but i'm just weird!

Haven't got to touch the stuff since college, used to love it, once I'd got the hang of it!

 

[imago]

Another thing to consider, if it's buried and he's cut through it, then it will be soaked for some distance in both directions from the cut. You'll have to cut back quite a lot of it to get a decent IR reading as a little bit of damp screws it, never mind open ends left in the ground. So you may end up replacing the cable anyway.

 

[MarkieSparkie]

As imago above says, it will be well and truly soaked, you will have to expose all the buried length to have any chance of drying it out and even then there is no guarantee of success, so you might just as well replace the lot with SWA and save both time and money. If you have to dry it out the best way in my experience is with a heat gun with a wrap around heat shield on a low setting working slowly from the terminated ends towards the cut section, but it's very time consuming (approx 15 minutes per metre).

 

[Guest111]

Another way to dry it out is to remove the outer pvc coating for about 2 feet then use a blowtorch to drive out the moisture,warm up the cable from the middle towards the end,seperate the cores and IR test then you will know you have dried it out before you seal it again,only dry it when you are ready to gland up though otherwise it will absorb moisture again.If I remember correctly pyro absorbs moisture at something like an inch a day in air,obviously this will be more in the ground though.

 

[UNG]

Is MICC allowed to be buried these days? Tell your client if he wants the job done he wants to have it done properly, I don't think I've heard anything so ridiculous as buried MICC this month. There's still time of course

There is a lot of petrol filling stations with a lot of it buried under the forecourts

Another thing to consider, if it's buried and he's cut through it, then it will be soaked for some distance in both directions from the cut. You'll have to cut back quite a lot of it to get a decent IR reading as a little bit of damp screws it, never mind open ends left in the ground. So you may end up replacing the cable anyway.

Depends on how old it is and which manufacturer produced it as some used a silicone based compound from the late 80's or early 90's to stop the damp problems

If you have to strip the PVC back to clear the damp use adhesive lined heat shrink or self amalgamating tape to make good and keep it waterproof

Used to love doing Pyro beats the alternative fire resistant rubbish thats rarely installed properly on fire alarm systems just a pity it's so expensive now

 

[clematis432]

Overall seems too many issues to repair this cable(dampness in damaged cable, waterproofing the joint, etc) and also if the cable was cut through, it cannot be adequately mechanically protected ? Replace with SWA or walk away.

 

[drew35]

Would rather do MICC than SWA anyday.

If he wont pay, crimp it and wrap a bit of tape around it.

Propeeeeeerrrrrrrrrrrrr jjjjjjjjjjooooooooooobbbbbbbbbbb!

 

[UNG]

Overall seems too many issues to repair this cable(dampness in damaged cable, waterproofing the joint, etc) and also if the cable was cut through, it cannot be adequately mechanically protected ? Replace with SWA or walk away.

The only issue I see is if you have the necessary experience with the cable type to carry out the repair properly to maintain the cable integrity

If an MICC has been damaged then replacing it with SWA does not solve the mechanical protection problem without other mechanical protection measures being deployed

 

[clematis432]

The only issue I see is if you have the necessary experience with the cable type to carry out the repair properly to maintain the cable integrity

If an MICC has been damaged then replacing it with SWA does not solve the mechanical protection problem without other mechanical protection measures being deployed

Surely Ung, SWA is a mechanically stronger protection than the thin copper sheath on a pyro ?

 

[trev]

Surely Ung, SWA is a mechanically stronger protection than the thin copper sheath on a pyro ?

Yes it is but you still have the depth, bedding, marking tape etc issues to deal with