PFC testing theory for Single Phase installations

This is an old video I made detailing the differences between Prospective Earth Fault Current and Prospective Short-Circuit Current testing.

[@banger50]

Excellent videos. I've just started watching them, and working my way through them slowly. They are helping no end with my studying!

[@artemlobov3685]

I couldn't get my head around Earth fault loop impedance testing, I thought that PFC was its own test and not a result of PSCC or PEFC. This video clears it up, many thanks.

[@simaxpix]

Thank you Mr Ninja : so clearly explained, like all your videos.

[@DanstheEngineer]

Another great basic simple video Sparky Ninja!

[@JURASSICDIVERUK]

Excellent video!

[@whopaimon5407]

Excellent explanation of pfc thanks

[@Sergey3023]

Brilliant explanation ⭐️⭐️⭐️⭐️⭐️

[@jimmyreid09]

Great video. Helped me a lot

[@michaelcostello6991]

Very good discussion. Thanks

[@quadrantheatingelectricspl2907]

Excellent explanation sparky ninja 🙂

[@alexwilliams9836]

Excellent videos thanks. Audio on all I have listened to could be a bit louder; been watching them in the van over lunch and I have my radio on max to listen and it's still not distinct.

[@josephking1947]

Very clear.

[@Azam94856]

I have a question regarding the difference between minimum prospective fault current (Ief) and maximum prospective fault current (Ipf). the question is the equation Ipf = (Cmax. Uo)/Zef, but for minimum Ief, do we use Cmin = 0.95 or Cmax = 1.1 ? it would be great to make a video regarding minimum and maximum prospective fault current

[@address191]

Hi sparkyninja, thank for all the content it is realy helpful, i was wondering if i have a three phase supply but only one phase is being used do i just treat is as a single phase supply, is there any risk of a high short circuit downstream if the supply cable was damaged?

[@JGE_Installations]

Another really good video. Did you do the follow up video e.i pfc on 3 phase? I'm very interested on your views regarding the doubling of pfc results. Had many arguements on site on this subject

[@bobbyzilla]

I always record the measured value and write X2 next to it. That clears up if the value has already been doubled or if it needs to be doubled.

[@154electrician]

If you where getting above 6Ka does your main fuse cover this or would it be a C1?

[@iraqviva7670]

I have fluke tester what shall use zi loop no trip or zi loop hi current

[@jbyfield8809]

Good stuff mate. Be good to see a segment on relating the Zs readings to the protective device disconnection times in BS7671, it may open a few more eyes, I witness this mistake loads when on site. People replacing an MCB to an uprated one for whatever reason and they deem it ok because they judge it by the circuits conductor size alone and do not consider the wider implications. Not good.

[@jamesgledhill9667]

Are they upgrading to a 10ka mcb?

[@peanutpotion]

If you was doing pfc both pefc and pscc on a 3 phase and neutral supply would you use 2 lead high Pfc - l1 - e / l2 - e / l3 - e taking the highest reading and x2 Pscc - l1 - n / l2 - n / l3 - n taking the highest reading and x2 If I’m wrong please correct me as I have an exam soon👍🏼 thanks for the vid

[@boden7815]

What I was always shown with my megger was disconnect earth to take a ze ( green clipped onto earth red to live and blue to neutral)note the top value for a pscc then reconnect the earth clamp green to the earth bar red to live and blue to neutral and let it do a reading then take the highest of them two readings.

[@bobbyzilla]

Yeah, that's not correct. Disconnect the main earth for Ze only. PFC with earths connected

[@ashleybignell2366]

What do you do in a scenario where your PFC is higher than the 6000/10000 KA rating of an Mcb? Great vid as usual.

[@SparkyNinja]

Hi Ashley, in these scenarios we need to either change the switchgear to higher ratings that can accommodate the PSCs or we need to engineer a lower fault current by introducing impedances into the circuit - this second option however is a big can of worms.

[@ningis21]

Hi Sparky... I recentely watched someone go through the motions...disconnecting the Earth from the CU....doing a Ze....and when I questioned why he had removed the Earth from the board and not the separate MET bar (where the TNS system and other bonding/earthing were situated ) ....because he had included the Water and Gas pipework in his test...he seemed a little flustered.....I metioned that it was the suppliers Earth (if you like) the he was testing...and that the Gas and Water would be included in the Zs test later.....He looked even more flustered. I left him to it....God knows the results.....and God himself will be able to explain it to the home owner or the sparks when they meet them/him...ha..ha..