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Consumer Unit Arrangement

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Static caravan of well under 100m2 is supplied from an external 16amp RCBO plugin box. 
This goes to the untouched, original consumer unit which has 1x 63A 30mA RCD and 2x MCB's (1 x 6A & 1x 16A).
That lot running a simple ring main (2.5 cable) of 5 sockets (4 singles, one double) and a lighting circuit (1.5 cable)
with LED lights and all works fine. 


Cooker/hob is gas and heating/water is via a newly installed gas combi.
The power supply to this was fitted by adding a junction box under the trailer and splitting the plugin supply 
to the boiler's own CU. 

As the load on the combi is very low and it's a minimal drain on the supply can't see it makes any difference, 
but what do you reckon, does all the above sound ok?  

  

Edited by Ed21

Sorry,  just to be clear, is it just the combi boiler supply that is new?

 

does it have a fused switched spur, to provide local isolation at the boiler.

 

hopefully it’s been spurred off the socket circuit?

  • Author

Yes  the combi supply is new.

The feed from the plugin has been split using an IP44 junction box underneath and the new
connection to the combi goes to it's own consumer unit with RCD & MCB  


The original wiring is untouched.   
The singular main switch for the whole lot is on the main supply of the plugin box.  

Edited by Ed21

Yes my main concern is earthing.  You should NOT connect a caravan to a TNCS earth.  Best to fit a local earth rod and connect the caravan earth to that.

 

Why not connect the combi boiler to a new MCB in the caravans consumer unit or is it that small it has no extra space?

  • Author

It has two earth rods, one for the supply box and one for the caravan. 
Here's a quick and dirty pic. 


 

CU .jpg

  • Author
7 hours ago, ProDave said:

Yes my main concern is earthing.  You should NOT connect a caravan to a TNCS earth.  Best to fit a local earth rod and connect the caravan earth to that.

 

Why not connect the combi boiler to a new MCB in the caravans consumer unit or is it that small it has no extra space?


AFAIK (the owner is quite elderly and details not always accurate) , the combi was supplied by a charity. 
It was professionally installed and I believe this is standard practice so as not to get too involved with the
owners main CU. 

It all seems ok, just wanted a second opinion as to what's there. 

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