Overhead Power Worry

[doit]

I have power via overhead line cables, from E/Board fuse to meter then to distribution unit.

I've just been told by someone that there should be a breaker of some sort before my distribution unit. Because of the type of system it is

Is this correct?????

 

[Big_Spark]

I have power via overhead line cables, from E/Board fuse to meter then to distribution unit.

I've just been told by someone that there should be a breaker of some sort before my distribution unit. Because of the type of system it is

Is this correct?????

NO it is not correct. AN Isolator can be fitted in this position, and apparently some suppliers do this if requested, but it is not a MUST do.

 

[ban-all-sheds]

An overhead supply might be TT.

It is possible that doit does not have an RCD CU, and has been told that he should put a stand-alone RCD in front of it.

 

[Big_Spark]

An overhead supply might be TT.

It is possible that doit does not have an RCD CU, and has been told that he should put a stand-alone RCD in front of it.

That MAY be possibl;e, but unlikely as most overhead supplies have been upgraded to TN-S supplies some years ago..although if he is super rural it is possible.

The obvious question is...Do you have an Earth Rod or does the Earth connection come from the cables overhead.

You can determine this by looking at the line in..is it Two or Three cables coming into the house?

 

[doit]

Thanx for your replies.

The property has a Wylex 10way Consumer unit with a 100A DP Isolator, the earth is via a separate cable running to outside. There are only 2 conductors coming from the overhead power lines.

 

[Big_Spark]

Thanx for your replies.

The property has a Wylex 10way Consumer unit with a 100A DP Isolator, the earth is via a separate cable running to outside. There are only 2 conductors coming from the overhead power lines.

Well that being the case Ban is correct and you have a TT system. I would suggest that you get in an Electrician to change the 100A DP for a RCD Main switch.

 

[doit]

Should this be supplied by the EB or by myself. Does this replace the isolator or work with it.

Sorry i'm a bit thick with electric.

 

[il78]

Would recommend that you call an electrician so that they can test the earthing arrangments and the installation. They can then advise accordingly........

 

[doit]

Earth is fine have rods at front and back. both labled as tested/installed 2002.

Can anyone shed any light on who's responsibility it is for the RCD, mine or the EB's

 

[ban-all-sheds]

My guess is that it's yours - I think their responsibility ends at the meter.

But it is only a guess.

 

[Big_Spark]

The supply authorities responsibility ends at the meter.

It is YOUR responsibility to ensure that your Installation complies with the Regulations, and the Regs recommend that all TT systems have RCD main switches.

I, personally, do not like RCD main switches, I would much rather see RCBO's placed on circuits that pose a real risk, such as sockets, but it is also a matter of cost for the individual.

 

[doit]

Thanks all. Will get it sorted as soon as.

 

[doit]

Hi All

Just to say thanks for your advice. had system checked and was "TT" as you said FWL_Engineer, Ban.

80A 30mA RCD now fitted and good earth confirmed.

Cheers

 

[Inspector]

All circuits at a TT supplied installation must be RCD protected. It is normal for 2 distribution boards to be installed at TT supplied premises (although split protection boards are available). If using 2 boards then connect the cable tails of each to ISCO connectors, and terminate the incoming supply to these ISCOs (this prevents overloading the dist board terminals).

Fit a 100mA RCD main isolator to dist board 1 (protecting the lighting circuits and other fixed equipment), and a 30mA RCD main isolator to dist board 2 (protecting socket circuits).

You'll find if you protect all circuits with a 30mA RCD that there'll be nuisance tripping and you'll be working in the dark to correct it.

 

[doit]

Have fitted only 30mA RCD to make system legal, as only had isolator switch. Will convert to split with 100mA RCD when conversion kit instore.

Thanks.