Recent content by Alanz1

I now understand this much better. Check you have the required current to trip an mcb within the appropriate time. Chart lists each current required, in my example. 383 amps wouldn't trip the breaker, adding massive heat to cabling or worse, fire. Many thanks to all who took the time to try...

Poni I think you explain that well. It's starting to make sense to me. Many many thanks for taking your time to explain this.

My lecturer says look at the table, all the amp ratings seem to trip at the same time, I just don't understand how to work the table.

I have the 18th edition book. I don't understand the characteristics table for type D mcb. I spoke with an experienced electrician today, he doesn't understand what the question is actually asking for.

I can't find in in the 18th regs book, so I think I got it from YouTube videos. I have used 230/0.6 for Zs reading, giving 383 amps. Now I'm trying to see if this current is suitable for a type D mcb. I'm looking at Characteristics table in regs trying to understand it 😩

I'm using 20 as the multiplier for a type D mcb (10 to 20 recommended) 5 is for type B 10 is for type C 25 a mp is current. Does that sound OK?.

Could you comment on my formula please Poni ?. 25x20 =500 230/500=0.46 0 46x0.8 = 0.368 Many thanks.

To be honest, I'm not sure. I used 20 times 25 (upto 20 for type d mcb times 25 for current). Any pointers ?

Many thanks Poni for your advice. My question states 0.4, so I assume that's 0.4 seconds. If the circuit is supplying a 5 KW load from a 25 amp type D MCB state whether a 0.4 disconnection time is possible and justify. Am I correct in thinking that my 0.36 ohms is acceptable ?. Been at this...

Hi Firstly, I am not a spark, merely mechanically qualified to trade, struggling with an electrical question at college. Could anyone assist with this question ?. A 230vac circuit with a Zs of 0.6 ohms on a TN system. 5kw load/25 amp type D MCB. Would a 0.4ms be possible ?. I have used 25x20...