Help and advice on garden junction box wiring

[solarmon]

Hi,

Just need some help and advice on a problem I'm having with my garden electrics. Please forgive some of my terminology as I am not an electrician.

I have an three-way junction box in my garden that spurs off (to a switch box for my pond pump) from an armoured cable going to the shed.

During the heavy rains the other week, the RCD breaker on my CU tripped and I figured it was to do with this junction box. I disconnected the armoured cable from the switch point coming from the house and turned back on the RCD breaker and it did not trip.

When I checked the junction box - which you can see is in a box in the ground - it had a lot of water ingress. The picture is shown after I had removed an inch or so of water and let it dry out a bit:


View attachment 15990

(The white thing is an old non-working water pump and not connected to any power - the white power cable is hanging loose)

You can see that it is a bit of a mess and there is lots of places where there can be water ingress. To my defence, I inherited this setup.

I thought that the three way junction box had also got water ingress in it and was causing a short and tripping the RCD. So I looked to replace this and to patch up the ground plastic box.

When I opened up the three-way junction I found this:

View attachment 15991

Apart from the rusting terminal block screws, the inside did not seem to be wet/moist/damp at all.

I have drawn up a diagram to show the cabling more clearly - you can compare with the pictures above:



My first question is, assuming the colours are associated with the correct power points - i.e. RED/BROWN = live, BLUE = neutral, YELLOW=earth, does this cabling seem correct? It doesn't to me as I would expect all the like colours to be connected together, as per?:



I suppose I will have to check the cabling at the house and shed end to see what colour cables are used for what.

Thanks in advance for any help you can give.

Cheers,

Mon

 

[malcolmsanford]

Welcome to the Forum

Unfortunately because your a new member your attachments are not loaded onto the site, you may have to use bucketshop and and link there.

I have to admit that if your first drawing is correct the blue does seem to be the Neutral and then you do have a mish mash of colours that do not make a lot of sense.

The Red SWA from the house would seem to be the line to the pump switch, and the yellow from the house becomes the red to the shed but whether that and earth or not is open to conjecture.

I personally would as you say disconnect everything, making sure it is dead and start to trace things out, if you feel competent to do this

 

[cobrauk]

I am unable to view the attachment so cant help you with your JB, I get
"Invalid Attachment specified. If you followed a valid link, please notify the administrator"

But if you drawing is correct you might have more then one live feed going out there using a common neutral
​

 

[clematis432]

Gardens,water,electricity don,t particularly like each other, and without proper protection are pretty dangerous. Probably best advice is to get an electrician to check it further.

 

[telectrix]

looks like both the red and yellow of the SWA are used as 2 live feeds. the armour itself must then be used as earth. making sure that this is glanded and made safe is a job for a sparks. as you know, water and electric can make a lethal combination, so i advise you to get a spark to give you a quote for making it work safely.

 

[solarmon]

Hi all,

Thanks for the quick response.

Not sure what happened with the attachments. I see that first two are just links - but if I click on it it shows the image.

When I connect just the armoured cabling together, colour for colour, the shed power works without tripping the RCD. If there were two live feeds, on YELLOW and RED cables, then would this actually work like this?

Cheers,

Mon

 

[telectrix]

from your pic. 1 , it looks like yellow id L to shed, and red is L to pond. the important part is the earthing. if this is achieved by using the armour of the cable, then, as my last post, if this is not glanded correctly and tested to be compliant, then you will have a dangerous situation that could kill. FFS , get a qualified sparky in.

 

[solarmon]

telektrix,

In the three-way junction box, the two YELLOW cables from the shed and pond switch didn't seem to be connected anything to earth it?

I'll check and diagram the wiring at the house and shed end to get all the facts straight.

Cheers,

Mon

(BTW - 'qualified' doesn't always means competent! :wink_smile:, and vice-versa)

 

[wade88]

(BTW - 'qualified' doesn't always means competent! :wink_smile:, and vice-versa)

No but being "qualified" appears a damn site closer to competent than you seem to be.

Not jabbing at you fella, just think now would be a good time to call a spark out.

 

[telectrix]

maybe if you post your location, one of us may be close to you and can pop over for a look a ---.

 

[grantr37]

resin jointing box =better

 

[monkeyelectric]

How is the swa connected at the house end? By the looks on your drawing the red and yellow are both lives so if you've now connected red ,yellow and blue to each other you'll have 230v in the earth on the shed! Unless they've used yellow as earth from the house then changed to red for shed, then shed shares the live connected at the pump end and pump has no earth at all! Either way get someone in or switch it all off until you find out whats what

 

[solarmon]

Hi,

It's all switched off - I'm not that incompetent. :teeth_smile:

This weekend I will trace the house and shed end to see how it is cabled and what colours it is using.

Cheers,

Mon