Ze and distance from substation

[ringer]

And it seems the Memera 2000 HRC fuse carriers have been discontinued, and they were only rated for fuses up to 16kA PFC.

HRC fuse carrier at RS

 

[Engineer54]

I've just re-read this thread, and it seems that the distance to the distribution TX is some 250 metres. We don't know the size of the TX though!! I would have to say that the supply cables would have to be sizable to allow a Ze of 0.01 ohm and a PFC of 19+KA. I would suggest that measurements taken have a largish error factor within them... You would only expect to see around 16KA in central London's DNO extensive networks.

250 metres is a fair distance, and when taking into account all the resistances/impedances of connections, switch gear, and cables etc, it's going to be highly unlikely that the given figures are anywhere near correct. Going by those figures the TX would have to be 1000 KVA, which would normally be capable of providing around 20KA into a fault at it's LV terminals, but very doubtful 250 metres distant, passing through all those said impedances...

To be totally honest, you would only find those figures within the actual sub-station itself or very, very close to it.

 

[ringer]

Took a while to get an answer to my original question, so thank you E54 for your last post! I was hoping someone was going to say that.

I hope to get the opportunity to take my own measurements sometime soon - I hate it when I suspect something is wrong, and cannot rest until i get to the bottom of it. My previous musings about SSC and HRC carriers were me trying to establish a plan B, just in case. Hopefully it won't come to that.