working out volt drop

[telectrix]

Reg 1: Use Common sense.

or it'll be something out of Chapter 3 about discrimination.

yes. i know, but was seeking a specific reg.

531.2.9 only asks for discrimination between RCDs when it is necessary to prevent danger.

 

[ImpededLoop]

I was always taught that the test button mechanically tests the device. I'm not sure about RCBO's.

 

[spark 68]

I was always taught that the test button mechanically tests the device. I'm not sure about RCBO's.

well yes to an extent, it checks the electro-mechanical aspects out, the test button usually switches a resistor from the incoming L terminal to the outgoing N terminal so it checks the trip coil operation too.

 

[Silly Sausage]

yes. i know, but was seeking a specific reg.

I know what you meant, I doubt there is one, you need the application of general regs.
Otherwise, the regs book would be bigger than The Encyclopedia Britannica to cover every scenario!

 

[Anthony S]

he is a trainee, i wouldnt be suprised if he is a first year

it sounds like a homework question, if it is its in the wrong section


he mentions mv/a/m on basic domestic circuits so its homework, why would you need to work this out when it gives you all that info in bs7671 and onsite guide if we wanted it

Sounds like he wants to do the job because he's applying for elesca registration in another thread he started.

 

[ImpededLoop]

well yes to an extent, it checks the electro-mechanical aspects out, the test button usually switches a resistor from the incoming L terminal to the outgoing N terminal so it checks the trip coil operation too.

That makes sense, but wouldn't cause an upstream device to operate as it only diverts current to neutral so no imbalance would be detected on the other device.

 

[spark 68]

That makes sense, but wouldn't cause an upstream device to operate as it only diverts current to neutral so no imbalance would be detected on the other device.

Hence my earlier reply to Lucien , I am not sure why the RCBO tripped out the upstream one that I did at work though, but it did.

I might tomorrow fit my spare RCD that I keep, to a plug and lead , and see if it trips out the house RCD lol

 

[Jonspark]

My downstairs sockets at home are fed from a rcbo and I spurred a outside rcd socket off this circuit, now every time I use the outside socket I always push the test button and it has never tripped the upstream rcbo.

 

[spark 68]

My downstairs sockets at home are fed from a rcbo and I spurred a outside rcd socket off this circuit, now every time I use the outside socket I always push the test button and it has never tripped the upstream rcbo.

I wonder if it only happens with an RCBO downstream ?, as I said maybe it was due to only certain types or possibly with the functional Earth when this is present.

I originally opened my mouth based on my earlier experience without thinking , then I thought about it and came around to Luciens way of thinking.

 

[Jonspark]

Always think before you type owt on here