snap clear pic of DB box's largest modules

Hi Sifu here, i using 3phase meter, but always jump switch during lightning.

what should i do to resolve this? thanks

Add in lightning surge protector

during the jump switch, thats without any electricity consuming. because the house is vacant.

Hi guys, I'm trying to apply 3-phase for a terrace house in PJ. The TNB tiang is right in front of next door neighbour (direct next door and not across the road), and the houses are only 22 feet wide, so need to dig around 20-30 feet to lay underground cable. The electrical company whom I'm making the application through (they are listed on TNB list of contractors) came back to say TNB is quoting RM20k to do underground cable. That sounds excessive to me. Any advice?

Hmmm.. is it because you are relocating your new 3 phase meter to somewhere else as well?

I did 3 phase recently... definitely not paying so much... what I recall is.. if i want to put my meter near front gate then i need to pay a lot like what you quoted. But since i want to save cost, i just put back the meter at the same location of my 1 phase meter.... probably paid less than 5k or even much less than that...

guys, i'm still confused about 1phase to 3phase.

landed house. supply is pulled serial stretching 4 houses. pre-existing 1phase with 60A fuse outside.

right now from reading TNB website, it sounded like i can magically change only meter and nothing else. please enlighten me.

--

(1) do i need to change meter etc outside? yes

(2) do i need to change fusebox inside?

(3) do i need to change lightning breaker?

(4) do i need to change breakers inside?

(5) is there new additional -whatever- at board inside?

(6) do i need to change wiring to wall switches, 3-pin sockets, and fixed appliances (including air conditioners, lightings, fans, heaters)?

--

just additional info; 8hp spread over 6 inverter airconditioners.

This post has been edited by Oltromen Ripot: Mar 28 2024, 08:14 PM

Simple answer is need to change everything except the wires that already inside the wall

Why do you need 3 phase? u are not running a bakery biz with full commercial ovens
Are you running all 6 AC at the same time? Even if you are -

-assuming
1hp x 5 unit at 4A each = 20A
1.5hp x 3 unit at 5A each = 15A
That's only 35A.

Still have room for other usage like water heater (15A each); but do note WH one unit eats at least 15A.

The thing is don't run all the WH simultaneously with all 6x AC can already.


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if all it takes is just to play with the 60A, possible for to get higher fuse, example 80A (i just tembak a higher figure as illustration of the intent)? or no possible with 1 phase? of course need to replace the related fuses and breakers, inside and out.

My point is if your existing is already 63A supply, and you haven't encountered the main breaker (without test button) tripping, then maintain as is - no need to change anything. If you're on 40A supply then need to upgrade.

You cannot|must not|pulis kata jangan|anyhow change the fuse|breaker to 80A WITHOUT the associated cable size upgrade.
This is because FUSE burn to protect CABLE. If you simply change the fuse to bigger one without upgrading cable, it become CABLE burn to protect FUSE.
This is a universal statement that applies to all circuits i.e. TNB to TNB fuse to TNB meter to DB box; and from DB box to all the little individual sub-circuits in your house.

The breakers in the DB box are already sized correctly for the existing installation. You can do a like-for-like replacement i.e. 20A to 20A, 6A to 6A, to refresh the DB box if you are worried its too old (>30 years). You cannot change the 6A to become a 20A.

If there is an anticipation in very high total load, it should be possible to either upsize or change to three phase but this will entail expensive cost of laying new cables TNB side w. TNB panel contractor to tarik cables. What I am suggesting here is if there is no real need to upgrade (based on actual load & practicality, whereby you can turn on everything and use a clamp meter to check your actual load amps), it's not worth it.

This post has been edited by ceo684: Apr 7 2024, 01:09 AM

it's <3yrs old.

i haven't sum the total possible amperage, but right now can confirm at least 5 a/cond running at same time, sometimes all 6. and people and tnb said general guide to consider 3 phase is more than 3 a/cond.

morning and evening - 2 heaters also running.
with internet, home automation, lighting, fans, cctv, freezer, coway dispenser, etc etc.
haven't moved washing machine and dryer yet.

so i am just exploring if 3phase is necessary before the house gets unwieldy to do anything anymore.
my wife bought house without consulting me; was coerced by developer to submit TNB form when collecting keys. I would have asked about 3phase upfront if i knew it.
it's late and expensive now, but i still have to enquire since i expect more appliances.

Hi all,

My new 'semi-d' house came with single phase electricity unfortunately and am currently exploring options to have it upgraded to 3-phase. From what I heard from my electrician, it seems that the supply from TNB to my house meter (at the front gate) is already 3-phase but this dumbo developer, for somewhat reason, pulled single phase from the meter to DB / house.

If I need to upgrade to 3-phase, need to hack the internal wires / cables in my house? Means from the meter all the way to the DB box? (in store room).

have u tested amp with multimeter during full run?

i tested mine 2.5+1.5+1.5 hp non inverter ac running together = 23amp

Yes (unless the wires are running in a service pipe and you can add wires without hacking)

Or just total up the HP and multiply by 5 for a rough estimate of consumption.

add 2 more 63amp+ wires from meter to db box

Thanks.
My DB box is placed in the store room and beneath it (on the cement floor inside store room) is a manhole cover with sands underneath. Any idea what that could be? A service pipe buried or hidden underneath?

Usually the cast iron cover will have a mark like Maxis, Digi, TIME, TM or something.

if square and cement one usually for telekom cable.

hi guys
my house is running 3 phase and currently I redo the whole wiring for the house. The electrician told me for main switch to use 63Amp and the ELCB 40A 300mA - one for switches and another ELCB 40A for 13A plugs. So when there is a trip, we can know whether it's from the plug or the lighting/fan. May I know if this is the right way to do?