suitable protective device for light circuts?

[paulthemagpie]

hi peeps,

just looking for some much needed and appreciated help

on an army barracks with roughly 7 to 8 buildings to the installation.

what would be suitable protective devices for the lighting circuts

thanks

 

[paulthemagpie]

im going to go for RCD protection with a type c circut breaker reason being the onsite guide recommends type c for banks of floresent lighting. on one of these building in question it has 50 x 1800mm floresent lighting so i feel thats most suitable.

what do you guys think. am i right?

 

[Richard Burns]

Sounds like you are just about there. 50 fluorescent lamps are going to have quite a current draw on start up so C type sounds justified.
You should consider why you need RCD protection for this circuit. have a look at 522.6.1.101/102.
You would need to justify your selection of these devices as you have done with the C type MCB.

 

[paulthemagpie]

okay, thanks richard!

so it needs RCD protection because of the metallic trunking? is that right

 

[Richard Burns]

No, the metallic trunking would obviate the need for an RCD (assuming it is earthed) as there would be an earthed metallic covering for the circuit.
RCD protection is not required for a lighting circuit even if the cables are run <50mm in a wall if the circuit is for use by supervised people, which one could possibly (sorry me being picky) say is the case in a barracks.

As far as I can tell for your circuit you would not need the RCD just the MCB.

 

[GLENNSPARK]

im going to go for RCD protection with a type c circut breaker reason being the onsite guide recommends type c for banks of floresent lighting. on one of these building in question it has 50 x 1800mm floresent lighting so i feel thats most suitable.

what do you guys think. am i right?

and what else does it say about discharge lamps paul?.....

 

[GLENNSPARK]

try looking on (p) 110 of the osg......look carefully.....then see what it says....

 

[Adam W]

im going to go for RCD protection with a type c circut breaker reason being the onsite guide recommends type c for banks of floresent lighting. on one of these building in question it has 50 x 1800mm floresent lighting so i feel thats most suitable.

what do you guys think. am i right?

You'd have all 50 lights in the building on the same breaker would you?

 

[paulthemagpie]

and what else does it say about discharge lamps paul?.....

sorry you lost me?

 

[paulthemagpie]

You'd have all 50 lights in the building on the same breaker would you?

hi,

thanks for your input, i do really appreciate it.

so i thought the point of a type c breaker was so you could have them all on one breaker?

or should it be split onto like 3 sperate circuts? and if that is the case does this mean we could go with a type class b then or would still a type c be needed

 

[Adam W]

Think about what would happen if the breaker did it's job if all the lights were on it, compared with what would happen if the lights were split into different circuits.
Also carrying out maintenance.
In what situation would you 'need' a type C? All the time?

 

[moehannadnowara]

whats the difference between circuit breakers type b c and d please

 

[davethsparky]

:bigcry:

 

[Dave 85]

Type C breaker allows for high start up current. Type B doesn't
If the barracks lighting is florescent then I would suggest a 10amp C type MCB would be a perfectly suitable protective device in most cases.

 

[davethsparky]

The OP has probably got it sussed by now, it was well over a year ago!

 

[ipf]

whats the difference between circuit breakers type b c and d please

A few pence, maybe.