RCCB's

[jameseye12]

Hi Guys, Just a quick one,

Assuming that RCCB stands for Residual Current Circuit Breaker, does an RCCB do the same job as an RCBO or an RCD or is it something completely different altogether?

Reason I'm asking as I came across 8 of these the other day, 40A merlin gerin, each feeding a stage lighting dimmer. These were the only source of protection on each circuit and as these dimmers can pull 60A at max, i wanted to make sure that there was some sort of overcurrent protection

Cheers

 

[Evans Electric]

RCCB offers no overload protection , same with an RCD .

RCBO offers both overload and current leaking to earth (shock) protection .

 

[jameseye12]

Cheers mate, that's what I kinda suspected.

Right then, replacing them with RCBOs

 

[Evans Electric]

Have you checked that there isn't one downstream first.

Although a lot of people think that RCDs offer overload protection because of the reference to the rating of the device , say 30A /30mA they think the 30A is the trip current . And thats quite a lot of sparks think that way . !!!

 

[jameseye12]

To be honest, the installation is a poor design. Each dimmer can take 12kw so should be fed from a 63a breaker. Considering most stage lights are about 1KW, heavy loading is likely. However each of the 8 dimmers is protected only by a 40A RCCB, the incomer is only 125A single phase so far too small for the anticipated load, even if diversity is applied. To be fair though, diversity doesn't really work here due to the amount of power that is generally used, different shows will need different amounts of power. Stupid thing too is that 125A breaker is located in a totally different building, inconvienent if the power goes during a show! However, a 4 core SWA current runs from the supply room to the dimmer room and only two cores are in use as its only currently single phase, so I'm submitting a quote for conversion to 3 phase 125A, so giving an adequate power supply for the installation.

 

[SPECIAL LOCATION]

Hi Guys, Just a quick one, Assuming that RCCB stands for Residual Current Circuit Breaker, does an RCCB do the same job as an RCBO or an RCD or is it something completely different altogether?

Reason I'm asking as I came across 8 of these the other day, 40A merlin gerin, each feeding a stage lighting dimmer. These were the only source of protection on each circuit and as these dimmers can pull 60A at max, i wanted to make sure that there was some sort of overcurrent protection

Cheers

As Dekeroony said....

Also you can check this in Definitions part 2 BS7671

near the top of page 29....

Red book... (not gone Green yet!)

OR..

in the BS numbers list..

BS61008

BS61009

page 236 of the book..

OR..

the little note on page 21 of On Site Guide..

:Salute