Garage Consumer

[britishrallying]

Hi,

If I have a split load C/U feeding another C/U in the garage (on the RCD side) do I need a RCD in the garage C/U?

2 circuits will be to power a socket in the greenhouse and pond pump, other 2 circuits will be lighting in garage and a radial socket circuit.

So will the socket in the greenhouse be ok as its protected by the 30mA RCD on the main consumer? Or is it just best to have a RCBO or RCD main switch in the garage consumer?

Just trying to keep cost down!! got a 5way consumer unit spare that I can use in the garage but has no rcd!

Thanks

Gaz

 

[davy_owen_88]

No you don't need RCD protection at both ends. It's beneficial to have the RCD at the garage CU and feed it from the non-RCD protected side of the house CU so that in the event of the RCD tripping you don't have to go back to the house to reset it. It also means you can install the garage lights without RCD protection so that you are not plunged into darkness which could put you in a dangerous situation if you are using powertools etc.

Oh, this work is notifiable by the way, so remember to notify it to your BCO before you start.

 

[britishrallying]

No you don't need RCD protection at both ends. It's beneficial to have the RCD at the garage CU and feed it from the non-RCD protected side of the house CU so that in the event of the RCD tripping you don't have to go back to the house to reset it. It also means you can install the garage lights without RCD protection so that you are not plunged into darkness which could put you in a dangerous situation if you are using powertools etc.

Nice one cheers mate!

Gaz

 

[Steve]

It also means you can install the garage lights without RCD protection so that you are not plunged into darkness which could put you in a dangerous situation if you are using powertools etc.

If the RCD were to trip, one would expect power to be cut to said power tools, thus alleviating any danger.

 

[davy_owen_88]

It takes my 131" bandsaw blade about 10 seconds to come to a complete stop after I hit the off button... it'll take less than half a second to cut off all my fingers... simple reason why my garage lights are not RCD protected

 

[Steve]

simple reason why my garage lights are not RCD protected

Are they fluorescent, all on one phase?

 

[davy_owen_88]

CFL's, single phase supply.

 

[Steve]

CFL's, single phase supply.

tut tut. are you aware of the flickering of fluorescent lighting, which when using machinery can cause a strobing effect, depending on the speed of the machinery? This can be unsafe for the operator.

You ought to have a small tungsten lamp near any machinery, so as to alleviate the above phenomenon.

 

[davy_owen_88]

I have heard of that, but the noise kind of gives the game away

 

[Steve]

(The reason i asked about phases is that you can also alleviate any strobing by putting the fluorescents across all 3 phases)

 

[nozspark]

If the RCD were to trip, one would expect power to be cut to said power tools, thus alleviating any danger.

If using machine tools (eg lathe) you should really have a non latching RCD to prevent them starting up after a power cut

 

[RF Lighting]

You can use lead-lag twin fluorescents on a single phase supply in machine shops, as each tube flashes on different degrees of the sine wave, so it is not possible for a moving machine to appear as if it is stopped.


My table saw takes a good 10 - 15 seconds to come to a complete stop, and it has a ruddy great limb removing blade just waiting to get you

(It has no volt protection too)

 

[JohnD]

I don't know if CFLs have a 50Hz strobe, like fluorescent tubes do. I was wondering only yesterday.

Who knows for sure?