- Reaction score
- 8
Hi everyone,
I appreciate this is probably a really silly question.
I’ve come across the below test question and although I know how to find the answer, I don’t understand why we would need to know what the max permissible earth fault loop impedance is in relation to a 30mA RCD? I hope someone can offer some simple logic as to why we need to know this?
The question is:
Calculate max earth loop fault impedance permissible for a 30mA RCD used to protect a circuit on a TN-S supply
A. Nominal voltage / RCD trio rating = max earth fault loop impedance
Again, it’s just the theory of reason behind the question that I’m struggling with.
Thanks again as ever.
I appreciate this is probably a really silly question.
I’ve come across the below test question and although I know how to find the answer, I don’t understand why we would need to know what the max permissible earth fault loop impedance is in relation to a 30mA RCD? I hope someone can offer some simple logic as to why we need to know this?
The question is:
Calculate max earth loop fault impedance permissible for a 30mA RCD used to protect a circuit on a TN-S supply
A. Nominal voltage / RCD trio rating = max earth fault loop impedance
Again, it’s just the theory of reason behind the question that I’m struggling with.
Thanks again as ever.