Afternoon all
I hope someone can shed some light on what i think is a problem with hevacomp connect, i am currently working on a large project and at the transformer, we have a fault current of 24kA but 10m upstream we have a fault current of 7.9kA so losing 17kA through 3 no. 185mm2 SWA cables.
I thought this may have simply been an error on this project due to entering something incorrectly but a colleague checked a calc they produced and the same happens, it seems the board downstream will let nothing more than 3kA through.
I have tried changing the protective device and this changes nothing on the fault current which remains at 7.9kA.
Any ideas / help would be greatly appreciated.
Andy
Hi Andy - I couldn't possibly comment without seeing the project. Please exit the software, go to your project folder, zip up the files and use this link to get the zip file to me.Thanks,
Duncan Brown
Hi Duncan
Thanks very much for the rapid response, i have sent it over and i hope it helps.
Andy - can you let me know what you are examining upstream? Is it a particular way?Thanks,
It is the fault current up to Block 3 End feed unit - BB/01-SA/B3/EF01 is the final value i need, handballing the calc we arrive at around 6kA. if we go from the transformer to MSB/SA we are going from 24kA to 6.4kA through 3 No. 185mm2 armoured cables.
Does that help?
Andy - you have used current limiting devices in the circuit (Schneider Compact NSX MCCB + Micrologic 2) - Under fault conditions, the current is limited. This document contains a little more information.In the example circuit, for example, the device on MSB/SA way 3 is an NSX400 N 2.3 50kA. If you examine the device data, you can see that the let through energy is going to be between (I haven't interpolated the figure exactly) 6 and 7kA.
Answer Verified By: Duncan Brown
Wow, thank you very much Duncan, i was dubious about using the likes of a forum to answer this simply due to never having used 1 before. I am sold, you have been excellent, thank you.
a colleague did say could the device be limiting the current.
Honestly, thank you. I will relay this back and may be back with more questions once i have spoken to colleagues
Happy to have helped.