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Ian1981

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Thoughts on this please, functional earth leads obviously showing signs of heat damage, the greenish coloured neutral leads compared to the blue ones are coloured throughout their length, maybe heat has caused this?
 

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Can't really see much from the photos, problem wise, mate.
I can't see heat causing the neutral problem and if the funky earth leads have heat damage, it's strange.
 
Can't really see much from the photos, problem wise, mate.
I can't see heat causing the neutral problem and if the funky earth leads have heat damage, it's strange.
I can’t see evidence on the neutral leads, they are just an odd colour compared to the blue ones we all know and can see in the picture.
The functional earths have suffered discolouration by I’d imagine, heat, them rcbos are warm to the touch.
Ive asked Schneider to see if they had produced such coloured leads , I’ve not heard back as yet, never seen Schneider rcbo neutral leads that colour.
The functional earth fly leads are also sticky to the touch
 
I can’t see evidence on the neutral leads, they are just an odd colour compared to the blue ones we all know and can see in the picture.
The functional earths have suffered discolouration by I’d imagine, heat, them rcbos are warm to the touch.
Ive asked Schneider to see if they had produced such coloured leads , I’ve not heard back as yet, never seen Schneider rcbo neutral leads that colour.
The functional earth fly leads are also sticky to the touch
If they were damaged through heat the RCBO's would be goosed. Are they operating?.....unless it's heat from another source. They were the usual cream/white, I take it. Are there changes in colour throughout the length?
Are RCBO's overloaded?
 
If they were damaged through heat the RCBO's would be goosed. Are they operating?.....unless it's heat from another source. They were the usual cream/white, I take it. Are there changes in colour throughout the length?
Are RCBO's overloaded?
Rcbos are operating and test within their perimeters.
The discolouration is throughout their length.
Rcbos are not overloaded and the odd one is still coloured cream , but not many.
 
Hi - if the insulation is tacky it’s breaking down rather than burning up, I reckon. Any chance of chemical pollution?
Well The DB is located in a cleaners cupboard which houses cleaning products, DB cover is correctly fitted etc.
The twin and cpc cables are fine tho, although they are LSOH cables.
 
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The only thing is see there that may give pause for thought is the effects of all lines being taped together. Presumably that is a functional DB, you should be able to detect any heat while it is drawing current. Perhaps all the bunched together lines are causing an effect with full current demand causing heating in an enclosed box and slowly "cooking" the cables above it. Maybe?
 
The thing is the "functional earth" is only going to carry the odd mA worst-case if the neutral goes open and so the RCBO's fire as a precaution. They won't self-heat. Also the discolourations is so uniform over many of them.

I would be suspicious of fumes from something strored the cleaner's cupboard (maybe in the past) that is behind this.
 
Agree with pc1966 if it was heat causing the diss colouration I would expect the colour not to be so uniform along the length of the cable, IMO any cooling effect the further away from the heat source would give a tapering effect of the colour, however fumes captured inside a cupboard may give that uniform effect.

Saying all the above the Green cable looks very purpose made.
 
Variation of colour in line & neutral conductors could equally be the result of two different brands of cable, given that colour is uniform throughout the visible length of each. Try comparing Pitacs with Prysmian and you'll find exactly this sort of variation.

The CPCs also appear to have two distinctly different sheaths.
 
I’m an idiot dryer and I think that this is obvious. They do make battery only units .

Variation of colour in line & neutral conductors could equally be the result of two different brands of cable, given that colour is uniform throughout the visible length of each. Try comparing Pitacs with Prysmian and you'll find exactly this sort of variation.

The CPCs also appear to have two distinctly different sheaths.
Doesn't explain the green neutral or the yellow RCBO earth fly lead? As far as I know all manufactures used white.
 
If the yellowing is caused by airborne contamination, I would expect that where the flyleads are cable-tied together, surfaces in close contact would be less discoloured. The discolouration could have occurred before installation, but it still seems odd that the neutral tails are so uniform as they would have been bundled up. I agree with posts above that heat alone is not the cause. Parts near the heat source would have burnt or melted before the rest had been so strongly affected.

It will be interesting to hear back from Schneider, but until they respond, I would not rule out the possibility that they are counterfeit. Schneider / Merlin Gerin MCBs have been faked in the past although crudely, they were merely switches with no tripping mechanism. But in my line of work we see fake products that can seem to work well unless pushed hard. Of course a faker would probably want to avoid any visual clues such as abnormal colours, but their QA procedure is probably less exacting than Schneider's.
 
Would be interesting to hear the outcome! Those functional earths are really yellowed compared to how new the rest of the unit looks
Schneider / Merlin Gerin MCBs have been faked in the past although crudely, they were merely switches with no tripping mechanism. But in my line of work we see fake products that can seem to work well unless pushed hard.
I have been installing some large air handling units and a chiller over the last week, the chiller control panel has a Schneider MCCB switch as an isolator and various Schneider contactors, none of them look quite correct. Hope they aren't fake too. The unit screams 'made in china' with it's sloppy construction and incoherent labels and instructions.
 

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