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MCB ratings

MCB ratings

MCB ratings

(OP)
lighting circuits on a remote camp site are wired in 2.5mm and protected by 16A MCB's.is this correctly rated? some circuits only have 1 or 2 lights on it

RE: MCB ratings

Possibly. The cable is thermally protected but you need to look at your earth loop impedance and the required disconnect time.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: MCB ratings

(OP)
im doing an inspection scotty,i thought 10A MCB would be suffice.the light switches are rated at 10A,so im thinkin about overcurrent protection to protect these?(highly unlikely due to little load tho)

RE: MCB ratings

Well, you need to size the breaker to protect the installation so yes, if you have 10A switches then a 10A breaker is a reasonable choice. You still need to check disconnect time and earth loop impedance - if this is a physically long circuit then you may have problems with a 10A breaker, perhaps with a 6A too. One way around that is to use an RCBO.

If some of that makes little or no sense then please get some help from an electrician - saving a few pounds isn't worth someone getting hurt or killed. And yes, I know how tight funds are at some of the Scout sites and similar having worked on a couple in my younger days when I had time to spare (pre kids!).
  

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If we learn from our mistakes I'm getting a great education!
 

RE: MCB ratings

Is an RCBO (or RCD) not yet a requirement for lighting circuits under IEC?  

RE: MCB ratings

IEC - not as far as I know.

The British regulations require an RCD or RCBO in areas where there is an increased level of risk such as circuits in a bathroom, but it there is no universal requirement for lighting circuits to be protected by an RCD.

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If we learn from our mistakes I'm getting a great education!
 

RE: MCB ratings

You also need to check for energy let through current and voltage drop.

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