Mine is slightly lower. It could be your old meter running lower after old age, mine go faster after old age.

This is what 1P vs 3P about.. 3P can support 3 time power load..

Suppose the power is over 1P can handle.. The fused will be burned.

If your house never experience power overload.. as I said let's said below 60A around 50A. Does changing 1P to 3P will affect electric bill?

If the power consumpt lower then 60A then the bill is still same

You need to calculate 3phase TNB fee + rewiring = justify the cost. Or Should I lower down my usage? Which 1 cost you more?

As long as your usage doesn't burn the main fuse, you don't need to change to 3phase. The main fuse burn is your usage benchmark.



And you can change the main fuse to higher. It doesn't limit to 60A. But not encourage. (Psst.. I didn't teach you this right.. )

My main fuse was rated 43Amp, it was given free to my by my electrician. The 60 Amps was taken by the ex-owner so no one can steal the electric during the SnP transaction.

I use for long, it never burned even all my 6 a/c switch on. Only later when I want to test full load, I swap back to a 60Amps.

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Added on March 20, 2012, 2:53 pmSo 60Amps really go long way.



This post has been edited by weikee: Mar 20 2012, 02:53 PM

i know 3 phase wiring is 3 16mm live wire + 25mm N wire into one db 3phase elcb. can we actually do this instead using 3+1 we do 1+1 16mm L+ 16mm n wire into 3 diffrrent db from the meter (each phase get each db (house got 3 db)) means we pull 6 wires instead of normal 4. ?

Don't understand. Can you draw out?

May way todo, some go to one main DB, and distribute out to another db, all depend on load how you want to do. And usually ground floor have all the 3 phases. Some design all terminate in one DB box (ground floor), and design have independent DB box per floor. If you have 3 stories, 3DB box. Some go direct to the meter. Each have its good and bad.

Usually first floor have a DB box with busbar for difference phase. If your load is not high on other floor, each floor will have only one phase. But if load is high on other floor, they will pull 3 phases to the floor, and distribute via busbar.

For my house, is single phase, but I have 2 independent DB box with independent ELCB. When ground floor trip, my first floor still ok, Vice-versa. (Technically, I can go 63 Amps x 2 but my limit on the main fuse. )

This post has been edited by weikee: Mar 20 2012, 04:15 PM

Neutral cable are usually same size as phase, some, which is not advisable, will put one size smaller to reduce cost, never see anyone put one size bigger for neutral.
Yes you can have single phase to each DB, just try to balance the load as much as possible. you will have to pull 3 cables for each DB instead of 5 cable for each DB.

Fuse is there to protect the cable from overvoltage. Make sure your cable able to take the load your fuse are rated at.

Fuse is for protecting over current. Over voltage will happen all the time, even under voltage. Some area swing around 240 +-5v

This post has been edited by weikee: Mar 20 2012, 08:42 PM

sorry i dont really know how to draw

Current set up single phase
Meter --- L 16mm+ N 16mm--- DB1 ---loop to ---DB2

Normally 3 Phases if I am not mistaken
Meter --- L 3x 16mm+ N 25mm (not sure is the correct size for N, read some where else)---DB1 ---loop to DB2

Can I just add 4 new 16mm wires (Examples)
Meter --- Phase 1 --- L 16mm+ N16mm to DB1 ---loop to DB2 (dont need to hack or disturb current wiring) (1x1.5hp ac + 1wh+ all lightings)
Meter --- Phase 2 --- L 16mm+ N16mm to DB3 (3x1.5hp ac + 1 Wh + Kitchen appliances + 10 13A Socket)
Meter --- Phase 3 --- L 16mm+ N16mm to DB4 (3x1.5hp ac + 2 Wh + 10 13A Socket)

Big house you have there. You did not mention where the DB box be? all same floor? If all same floor, you better of using a bigger DB box, as all fused and ELCB in once area.

Looking at your summary, your DB 4 have risk of overload too. Say if you switch all the equipment same time ( 3x 1.5 HP = 3600 Watt +-, 2x WH = 6000Watt, if someone use Iron, and put in some high current equipment e.g. Vacuum cleaner say 3000watt) You already use 12,600 Watt about 52 Amps. Few more socket you go above 63 Amps.

wei kee, small house only 22*75 5room+4bathroom. so house need 4wh. 7-8 ac. i wont pasang straight all the ac, except their piping and wiring.
ori wiring only got 1wh + 1ac point so really need to do wiring.

You plan to use instant or storage WH? If storage maybe you can consider solar since you have 4 unit. You save the money from 3 phase and use it on Solar. Maybe top up 1 to 2k

Hi

I have asked my developer to change my wiring from single phase to 3 phase. I was charged RM3200 for below job.

SUB-MAIN 3 PHASE
3PHASE DB
METER BOX AT GATE
SUB-MAIN FIRST FLOOR

Now they finish the installation of the DB Box. But I don't know if they use the good DB box or not.
The MCB brand is Wynex.
And it only have 15 fuse.

Can anyone experienced in this area help me? Is the price reasonable and is the material used is a good one.

Thanks...

Wow, 15 fused with 3 phases. I feel is over kill.

I plan to use intant wh one. i think its alot cheaper. wh with pump is around 450-550. so total will be around rm1800-2200. if used solar one need to do piping which would cost alot of money. now i would only need to do wiring for 3 toilet, which is only around 350 additional.

*when i move in i will only install 2unit first...budget problems

This is usually how a 3 phase wiring look like

http://www.electrolesk.com/Work/Wiring%20o...ion%20Board.htm

But of course separate DB also been practice.

wei kee, those diagram is for one db with 3 rows?

Thanks weikee for the info.

Anyway is the WYNEX brand is a reputable brand? Since I don't have any knowledge on this area, I afraid if they give any lousy brand and later have problem.

My parent house also using 3 phase (12 years old house), but the DB Box is much bigger using metal cover (schupa brand - from German)

But my DB box seems to be quite small with plastic fitting outside. looks cheapo to me...

Thanks...