sorry because of my poor english.
some ppl they may have misunderstand something.
if u using a 2.5hp or more than that air-con, pls choose any 3-phase type air-con,more efficensy n save money.some ppl they though their house is 3-phase,than they go n buy a 2.5hp single-phase air-con will save money,thats wrong. u need to c the eer value, some product if even u install an 1hp + 1.5hp = 2.5hp , the electricity more saving than the 2.5hp 1phase, n if u can ,install an 2.5hp 3phases type u can get the more eer value.
y ppl say that 3 phase wiring is more saving form 1 phase?the waste of energy from wire heat
first ,u have to determine how is the maximum amp of ur house will use?..mostly electric appl will show at behind sticker. add up all.
if a max of 60A , and ur house is wiring with 65A wiring, n sometime u feel the wiring will get a bit warm or hot, that the part thats waste energy, so, use an 100A type wiring will save them.always remember, any part of wiring or switch or mcb,elcb,rcb ,fuse bla bla, that all are warm,hot are adnormal, n wasting energy, the cause was:
1.wrong amp rating,wire, mcb,elcb,fuse bla bla.
2. connector connection not tie enough.
3. short circuit bc of mice bit,moist.

so if a 100A of max how?(is that ur house is a factory?).. apply 3phase to dist them.

every house is 3phase ready(even 100years ago), unless the contractor using only a main wire pull from room1 to roon N. bc most of our nation resident using 3phase for dist current only, but not using 3 phase appliance..

This post has been edited by yi_min82: Jan 23 2011, 12:35 PM

sorry about my language.
wat i mean 3phase in our resident house is not actually with 3phase wiring,it only reach until the Db box. actual 3p wiring for appliances had to have at lease 4 wire (r,s,t,ground),sometime it add 1 more (r,s,t,n,ground),not like 3wire(L,g,n).
eg.acson or york cassette type 4hp.
eg.ceiling type or concealed type
mostly they install at living room.

3phase 4hp, n 1phase 4hp, witch one current using more ?1phase right? so the current flow more n generate heat or lost energy because of resistance. btw,yup, its not primary,but second . so conclosion, 3phase save more with 3phase appliances.

"About the energy loss via resistance, I am not too sure about that."
resistance in the wire. most contractor cone ppl with the low quality n small diameter wire, it increase the resistance. cause it generate heat, waste the energy n make the wire life shorter. Or , the user didnt mention to the contractor, after that they use it with high current appliances like water boiler, high power entertainment set, laser printer, hair dryer and etc. P.S. notebook consume very low power only.

This post has been edited by yi_min82: Jan 26 2011, 09:50 AM

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