what rcd amp size?

paulthemagpie · Mar 15, 2012

hi,

what RCD amp size to power an outbuilding that has 4 x 2 gang switches, 2 x 1800mm twin florensent lighting, 3 x outdoor flood lights, 1 x multi-gang single pole switch

also im guessing it would be best to have another distrubution board out in the outbuilding?

thanks you for any help that is given

Dean · Mar 15, 2012

Give the guy a break! He's only trying to learn! We all started somewhere.

DPG · Mar 15, 2012

It's only a question. Just wondered if he knew. Still don't know if he does. Wan't meant to be derogatory. Daz

paulthemagpie · Mar 15, 2012

Dean said:
Give the guy a break! He's only trying to learn! We all started somewhere.

thanks! lol

anyways yet i have covered mcbs, rcds, ect but with the course being home study they expect the material to give me to be a guide and i need to find extra info else were. Such a pain I know.

TBH im not just after the answers i also want to knwo why.

I do spend time working backwards so i understand exactly the subject and im finding that alot more useful as you guys are the experts and i appreciate all the info you tell me.

im not here to leech and can promise to return the favour and hang around and answer other guys questions once i get more knowledgeable and even donate some money to the forum if im getting the help i need!

Richard Burns · Mar 15, 2012

paulthemagpie said:
hi,

what RCD amp size to power an outbuilding that has 4 x 2 gang switches, 2 x 1800mm twin florensent lighting, 3 x outdoor flood lights, 1 x multi-gang single pole switch

also im guessing it would be best to have another distrubution board out in the outbuilding?

thanks you for any help that is given

Paul
Just to clarify an MCB (circuit breaker) is a device designed to trip if there is overcurrent or fault current on the circuit it is protecting.
An RCD is a device designed to trip if there is a very small current flow to earth (determined by the difference in Line and neutral currents)
An RCBO combines both the above functions in one device.

When you ask what "RCD amp size" this is not readily answerable as RCDs operate on mA not amps.
RCDs do have a ampere rating that determines the maximum current that they can handle in terms of it flowing through them but this is down to the physical capability of the components to handle this current and is not associated with the protective characteristics.

From your question there is no indication of the total load that would be drawn as switches do not draw current and there is no indication of the power of the flood lights or the fluorescents.

So the question as stated is not anawerable from the information given. We could give an idea of what current handling capability you would require from an RCD on a general lighting circuit but this would not answer the specifics.