Simple Way to Calculate Short Circuit Current Using Point - to - Point Method 

Salamat sir

Salamat sir for watching my video

Sir may question po ako, yung 500kva 3phase transformer po ba single phase pole mounted transformer na naka banking lang po ba na consist of 167kva each rating ganon po? Parang sinum up lang Sir? Thank you po. ​@@RandyAmorchannel

Thank you sir. God bless

You're welcome sir

Pag point-to-point method ang gamit mo kailangan mong mag simula sa source papunta sa point of fault kasi may factors na magdedepende sa fault current upstream ng fault point na gusto mong kunin.

Smath Solver sir, may video ako kung paano mag download at gamitin ru-vid.com/group/PLfGtZkfoxIwyw55mf2kqRSNfz86rOLRuK

Nakita ko Engr sa suggestion.. salamaat ng marami.

Thanks for the comment. I will try to put english subtitles to it.

wala pa sir, try ko gawan next time. Thanks

@@RandyAmorchannel Salamat sir!

Kasama po yan sa analysis na ginagawa at pinipirmahan ng PEE. Normally separate sheet sa A4

Yung n dun sir is number of parallel runs, in that case, n=2

​@@RandyAmorchannelKunwari po 3 na acb galing sa hvsg to lvsg. So times 3? Tama po ba

@@jeffreymanalomanalo2682 hindi po ganun sir. Yung number of parallel runs of cable po is kung ilang set ng three-phase cables and ginamit, for example kapag nakalagy sa single-line diagram na 2 - 3Cx100mm2 ibig sabihin 2 sets ng three-phase feeder so ang n=2

Kung 1 set lang n value is 1. Kung 3 sets ang n value is 3 di po ba?

Sa utility po yun sir, kVA rating ng utility transformer

Sir with regards to voltage used, ang voltage drop sa buong system ay limited to 3% from source to last point as per standards, so negligible na yung voltage drop. Kung gusto talaga nating gamitin yung actual voltage sa point of fault, pwede din naman pero mag calculate ka pa ng voltage at every point. Salamat sir and God bless.

Yung point-to-point method, sabi ay kapag hindi significant yung motor contribution at pwede nang hindi isama. Sa dulo ng video pinakita ko yung fault currents at different points of the system with and without motor contribution. Salamat sir. God bless

Sir sa design po yun makikita normally naka indicate sa single-line diagram

Consider mo yung length hanggang transformer kasi may contribution yung transformer sa fault current

Yes po sir kailangan i-convert sa feet kasi yun po ang nasa formula

You may download the file from my Facebook Group facebook.com/groups/usapangelektrikalph/files/files

Smath Studio sir. May tutorials din ako tungkol jan ru-vid.com/group/PLfGtZkfoxIwyw55mf2kqRSNfz86rOLRuK

@@RandyAmorchannel salamat

constant po yun sa formula sir.

ano ang formula?@@RandyAmorchannel

@@Dragon26-Tiger31 sir nasa video po ang formula M=100/(%z x 0.9)

Ang alam ko PU method ang accepted ng OBO for permit. Dapat na siguro mag update ng OBO sa acceptable method of calculation ng SC to include other methods. Pero magagamit mo tong methid na to for quick calculation para sa KAIC rating ng equipment

Gamit ko Smath Studio

sir pagdating sa breaker na gagamitin base sa na calculate ng fault current, ang rule lang naman dun ay kunin mo yung breaker na may kAIC rating na equal or mas mataas sa calculated fault current.

@@RandyAmorchannel thanks

Yung impedance ng transformer varies depende sa capacity at sa manufacturer din. Makikita naten ang % impedance ng transformer sa nameplate. Salamat sir question mo sir. God bless

@@RandyAmorchannel Sir kung walang nakaindicate na impedance sa nameplate, ano ang gagamitin na impedance?

@@marvin082500 standard nameplate ng transformer shall always include impedance. Pero kung di available for example eh nabura na or nawala yung nameplate, etc at wala kang sources ng information tungkol sa impedance, pwede kang mag refer sa IEEE std 142 or yung Gray Book. May table dun na Approximate Impedance Values.

Thank you Sir @@RandyAmorchannel

Smath Solver (formerly known as Smath Studio) sir gamit ko jan. Free alrernative to Mathcad

Yung 100 sir ay kasama sa formula yun

Same lang din. Naka dipende naman po kasi yung C values mainly sa wire size, then kung magnetic or nonmagnetic yung conduit, tsaka yung voltage.

Walang separate value for single phase. Magkaiba lang ng value for single conductors and multi-conductor cables or kung busway

Sir yung 5% impedance po ay given sa problem, pero sa actual na calculation kukunin nyo po ang impedance sa nameplate ng transformer. Salamat po sa panonood sa video. God Bless.

Malinaw naman po yung video.

@@RandyAmorchannel Hello po Sir Randy. Blurry sa cellphone ko sir. But clear sa laptop. Maraming salamat po sir.

@@RandyAmorchannel Hello Sir Randy, tanong ko lng po kasi nalilitu po ako. yung impedance po ng transformer is 5%. Yung tanong ko is M1=100/(5)(0.9), since 5% po yan sir hindi po ba dapat 0.05 ang gagamitin natin Sir? magiging M1=100/(0.05)(0.9)?

@@OP-OP999 kung ano po yung naka indicate na %Z ayun po yung gagamitin hindi na po gagawing decimal

@@RandyAmorchannel got it po sir. Maraming salamat po at binigyan niyo po ako nang kalinawagan.

Ginawa ko muna boss sa powerpoint then copy & paste