black sticky liquid??

[Edd]

cables dont run through a roof space and been pulled through roofing tar, and the poor sparks got covered and couldnt be bothered to clean it off befor doing the board.. been covered in sticky crap like that before and got it everywhere, just dont come off

 

[Dean Williams]

thats a good point. the school has a flat roof and most prob has had bitumen or something on it. i'll have a search tomorrow.

 

[Darkwood]

Couple of points here, doing my csi... the likely cause is leaching of plastercisers out of some of the older cables, the majority in your picks is second hand contact (transfer) probably caused by other sparkies getting it all over their hands like yourself too, for the plastecisers to leach out their has to be a chemical reaction and may have taken decades this could all come down to the original installers greases the wires to drag them in or as mentioned before the tar issue is a likely cause too, if they were dragged through tar (even set tar) they will have black streaks rubbed onto them, tar reacts with the pvc causing leaching of the plasticisers which in turn liquifies the tar to a sticky goo. The issue is that when the plastisicers leach the cable insulation can change it properties for the worse, ive seen insulation showing 230v to earth before where leaching occured.

 

[Darkwood]

Or the obvious one is the previous sparky left his bag of liquorish allsorts on top of the dist board,....... give it a lick :wink_smile:

 

[Dean Williams]

cheers Darkwood. most of the goo was tacky, but some had set a bit and when i picked it off, the insulation came off too. i originally thought that it was some sort of plasticiser migration, i saw a similar thing at a theatre i tested last year, except it was green goo...the dreaded migration of the plasticiser di-isoctyl pthlene.

 

[SPARTYKUS]

my money is on roof tar, awful stuff.

What a mess!

Just spray a can of WD40 into the CU........ !

 

[Darkwood]

Its always hard to pinpoint without knowing the full history but i do recall seeing old pvc cables run over tar in a cellar and it layed in a line of sticky wet tar where the rest was solid, its seems that both react to each other and yes its a 'bitumen' to get off your hands (see what i did there! lol).... , but im on the understanding modern cables dont suffer like the old stuff but are prone under the right conditions.

 

[Darkwood]

my money is on roof tar, awful stuff.

What a mess!

Just spray a can of WD40 into the CU........ !

Only if your trying to blow it up!!!!!!!!! I seriously hope this is sarcasm!!!!

 

[SPARTYKUS]

Darkwood


Worry ye not. Meant to be sarcastic!


Want a quick flamethrower? One match, can of WD....

 

[Darkwood]

Darkwood


Worry ye not. Meant to be sarcastic!....

A emoticon of destruction would have been nice on this one as it can come across as advice to those who dont know its conductive, flamable and eats many types of plastic even i had to check your post was siding with humour.... ive seen an apprentice turn a motor into a ball of fire before with WD40! :willy_nilly:

 

[vernam616]

With you mentioning it was a school is the cabling ran in conduit?

Once had a job where there was a greeny black goo on the conductors just like that in your photo, turned out it was a lubricant they used years back to pull cables through the conduit easier

 

[ackbarthestar]

I remember a job we did. Before the galv conduit was buried in concrete we poured bitumen over all conduit and trunking system. Now if there was conduit set in the flat roof some of the tar may have seeped into a part of it and when the cables were pulled through at a later stage had picked it up. rather than cleaning it up the installation sparks just left it as is.

 

[jimmymac]

I think it's Anti-climb paint, formaly known as Vandal grease. One of my mates is a school janitor and he's always covered in it. I bet the jani was poking around in the DB with his paint brush

 

[Dean Williams]

Thanks for all your replies. After a bit of searching today i found the culprit. as most of you said, it was.....wait for it........Bitumen.
i got into the roof space and found it had dripped down walls and was all over the place.

 

[SPARTYKUS]

A emoticon of destruction would have been nice on this one as it can come across as advice to those who dont know its conductive, flamable and eats many types of plastic even i had to check your post was siding with humour.... ive seen an apprentice turn a motor into a ball of fire before with WD40! :willy_nilly:

You know what, you're right, sorry should have made sure blindingly obvious!

Point taken darkwood. :82::82::82: