Advice on fixing this outside mess

[RDB85]

Basically I’ve attended a friend house who asked me to see why his power to his sheds had stopped working. Any help or advice on fixing this mess please

 

[timhoward]

I know we all make mistakes. I’ve learnt from it. Every day is a school day as the saying goes. If designing the circuit the CCC Table 4D2A

3 core in conduit is 27 amps in Conduit and 32 amps Clipped Direct.

Agreed. Has the penny dropped that this presents a problem?
If the cable is at risk of starting to melt above 27 amps loading, is a 40 amp MCB of any help to avoid this scenario?

 

[Diddy]

Agreed. Has the penny dropped that this presents a problem?
If the cable is at risk of starting to melt above 27 amps loading, is a 40 amp MCB of any help to avoid this scenario?

Would installing a big --- fan blowing along the length of it help at all ?

 

[davesparks]

What could I use to join the two boxes. If I have a Wiska box below and the RCD Enclosure above it.

If you are replacing the supply cable then take it straight to one of the sheds instead of trying to patch up that mess.

Don't just repeat the mistakes of the previous installer, think the job through and do it better than they did.

 

[RDB85]

Agreed. Has the penny dropped that this presents a problem?
If the cable is at risk of starting to melt above 27 amps loading, is a 40 amp MCB of any help to avoid this scenario?

Okay so I’ll. change the protective device.

 

[RDB85]

Im still somewhat intrigued as to how you have identified a break in the origional cable

Cut it where ? Inside the consumer unit or elsewhere. Is it the case that the cable is inches short now or is there an as yet unidentified break in the original cable? Ir came back nothing ? Unsure what that means. Continuity came back nothing - I assume that means you didn't get a reading when you tested each core to say earth for continuity ?
But how could you test for continuity without opening up the consumer unit 1st ? You do know to do a continuity test you must somehow create a loop for the test to be conducted. Be that through a long lead or using traditionally the earth as your potential loop .....and so on.
I still think you should be mentored for this instance just so that you have the practical knowledge next time. But if my questions and what I have said sound harsh there IS a point to them - You could be turning a 30 min fix into a day long job....even if you are doing it for a friend and doing it free of charge so no ulterior motive....It's simply preferable to fix what is there (If no unidentified break in the cable elsewhere) as opposed to starting again ....I/We are trying to save you some time and possibly money and as already mentioned maybe even saving you from installing a cable in a manner that renders the install "incorrect" with regards to cable size and OC protective device selection....

The cable has been completely cut somewhere in the garage ceiling. That’s why there was no reading. But as it was late and I’d seen the RCD had tripped and noticed the water ingress. I THEN went and looked in the Consumer unit and when trying to get continuity. There was no reading.

 

[nicebutdim]

The question I'd start out with is "what does your friend want to achieve?" and work backwards from that point.

Form the bare bones of a plan on the basis of their requirements, rather a length of cable you have to hand.

 

[westward10]

It’s about 10m 4m is a straight run horizontal. Then there is a bend around the corner. 4m straight run and then 2m vertical.

Good luck with that.

 

[Diddy]

The cable has been completely cut somewhere in the garage ceiling. That’s why there was no reading. But as it was late and I’d seen the RCD had tripped and noticed the water ingress. I THEN went and looked in the Consumer unit and when trying to get continuity. There was no reading.

That is now very clear and a replacement cable may well be the "best" solution. Now you would want to enquire what amount of power these units need. If it's somewhat less than the original 40 amps then cool, downrate the cable and the protective device. If Not then you simply either find the break and repair what's there OR install a cable rated the same as what's already there. I mean lets be clear, a whole new cable including conduit and a 10+ meter run which will all take time and money for materials is usually one of my last resorts in this type of scenario......it would seem slightly "mad" for someone to have cut the original cable to such an extent that it was now totally unusable and redundant, but then again you just never know with people.

 

[westward10]

Maybe it isn't cut at all as it hasn't been observed. Maybe it runs through another isolator.

 

[RDB85]

That is now very clear and a replacement cable may well be the "best" solution. Now you would want to enquire what amount of power these units need. If it's somewhat less than the original 40 amps then cool, downrate the cable and the protective device. If Not then you simply either find the break and repair what's there OR install a cable rated the same as what's already there. I mean lets be clear, a whole new cable including conduit and a 10+ meter run which will all take time and money for materials is usually one of my last resorts in this type of scenario......it would seem slightly "mad" for someone to have cut the original cable to such an extent that it was now totally unusable and redundant, but then again you just never know with people.

Okay so I’ve looked at what is currently fitted in the shed it has a small chest freezer 0.75 a 36w LED Light and a 44w LED Light. So I’ve worked out to 830watts so about 4 amp when divided by 240v.

 

[nicebutdim]

Maybe it isn't cut at all as it hasn't been observed. Maybe it runs through another isolator.

I'd pondered exactly this, but thought it unlikely that an isolator wouldn't have been left in an accessible position. Who knows?

 

[RDB85]

My friend also informs me that his mums bought a Lazy Spa. The 40a Type B MCB has been changed to a 20 amp. Looking at the power consumption and the lights and chest freezer it’s just under 16amp. Plus the RCD which is recommends in the manual.

 

[oscar21]

I'm not sure why some people make this assumption, but it certainly calls their competence into question.

Would they make similar assumptions about the rating of an isolator?

In case you hadn't noticed plenty of people who "mess" with electrics - kitchen fitters, DIYers, Dave from the pub and remarkably quite a lot of practicing electricians have zero competence. I just thought this one set them up way too easilly to fail.

 

[nicebutdim]

In case you hadn't noticed plenty of people who "mess" with electrics - kitchen fitters, DIYers, Dave from the pub and remarkably quite a lot of practicing electricians have zero competence. I just thought this one set them up way too easilly to fail.

Why should an industry adopt new practices to accomodate people who have no business using their products? Everything they need to know is either printed on the RCD or in included instructions - I doubt an extra warning label would encourage them to become any less ignorant.

 

[RDB85]

In case you hadn't noticed plenty of people who "mess" with electrics - kitchen fitters, DIYers, Dave from the pub and remarkably quite a lot of practicing electricians have zero competence. I just thought this one set them up way too easilly to fail.

Are you referring to me?