I'm currently just at the start of my electrical training so please excuse what may be a dumb question. It's a few weeks till I'm back at college and so not able to ask the question there.
I want to understand a bit more about cable length. If you're using an MCB as overcurrent and fault protection then cable sizing, length etc clearly have an effect on Zs and therefore you may not make the fault disconnection times. If you have a situation where you don't meet the Zs requirements for a circuit, say on a TT system, so you are relying on RCD protection for fault protection, I want to understand two things:
How does cable length affect the response time of the RCD, say 30ma in this scenario? As the cable gets longer does it affect the tripping time?
Does cable length affect the MCB/Overcurrent operation to protect against fire if the circuit is overloaded but there are no fault conditions present?
If anyone can explain this to me that woiuld be great!
I want to understand a bit more about cable length. If you're using an MCB as overcurrent and fault protection then cable sizing, length etc clearly have an effect on Zs and therefore you may not make the fault disconnection times. If you have a situation where you don't meet the Zs requirements for a circuit, say on a TT system, so you are relying on RCD protection for fault protection, I want to understand two things:
How does cable length affect the response time of the RCD, say 30ma in this scenario? As the cable gets longer does it affect the tripping time?
Does cable length affect the MCB/Overcurrent operation to protect against fire if the circuit is overloaded but there are no fault conditions present?
If anyone can explain this to me that woiuld be great!
