currently using 3 units at home, plan to install another unit, will tripping the circuit breaker anot? anyone

your house how many phase ? and what other eq you running 24/7

Change to 3 phase wiring

not sure bro, how to check ya? running mostly at nite

ask electrician

You have to move beside TNB substation.

it will trip

Call certified electrician. Those aircon technicians will always say can can. They just split wires ok done.

No problems.

Take a picture of your circuit breakers aka fuse box and post here

It will not trip la. Especially if you have those inverter air cons.

Aircon take a lot of power during startup. Those old days aircon they will start stop often. Unless all your 4 air con starts at the same exact time then it might have issue. Just make sure the surge will not exceed the MCB rating lo. Don't fall for the bullshit that we need to change to 3 ph. They just milking money.

1HP aircon only 3A lo.. (700W or so)

your house is 60 or 100A

5 1HP aircon also no problem lo.

wait

here u go

Macam one phase only

huh? how now? cant use?

whats wrong with 1 phase? do you know how many amps can pass thro that box?

have to change to 3-phase like those use for killang use one.

Did I say there is anything wrong?🙄
I was answering his question how to check how many phase

This post has been edited by idoblu: Dec 25 2016, 08:46 PM

yes your remark very useful,
might as well say wow its a white plastic box.

Forgot to add fridge, washing machine, 700w mustard race pc 24/7

I can't help it if you can't read
Whether it's useful or not is not my problem

Another person was asking how many phase TS has
TS asked how to check
I'm just telling him how

This post has been edited by idoblu: Dec 25 2016, 08:51 PM

if the house electrical cant take those loads mention and 3 aircons, better sell of the useless house.

I think Can. Just make sure the source is from different circuit breaker that other airconds are connected to

My house 1 phase, 5 ac. No problem

2 refrigerators, 1 washing machine, 3 units pc

living hall one is 1.5hp, my room 1hp, another room 1.5hp, plan to get another 2hp aircond, normally 2~3 units at the same time, but if got relatives come, will on 4 units at the same time

adding aircond is not increasing the load?

maybe you are an expert, where else i'm just someone who have design and start up a few Cogen plants. Yeah, so please go ahead and explain to me the whole electrical loading concept again.

so we are suppose to listen to some school dropped out like you then?

unless he have a lift in his house

Because of one person, whole Taman Blackout

JK

It's about balancing the load

Where to hire certified electrician?

make sure the cable at switch breaker can sustain the max load. if not, the cable will heat and maybe burn or short and faiya.. but dont worry the breaker will trip before that unless the breaker already change to high load.. and still using old small cable

You do have 3 phase equipment maybe those needing those 400 plus volt eq in factory. But in house if TNB just give single phase means we only have certain Max amount of load depending on the Max current through that single phase. Additional phase is just like adding a parallel load sharing thing. Right?


From tnb website:
Single-phase vs. Three-phase Supply
A single-phase meter measures usage from a 230 volt supply through two (2) wires, while a 3-phase meter measures usage from a 415 volt supply through four (4) wires.

You are advised to change from a single-phase supply to a 3-phase supply when your household electricity load exceeds 10kW or 50A. Generally, you should change to a 3-phase supply if you have three (3) or more air-conditioners in your home.

Upgrading to a 3-phase supply will increase stability and reliability of electricity supply to your premises.

This post has been edited by Xcal: Dec 25 2016, 09:52 PM

Agreed, we talking about power efficiency no doubt u can run 5 ac on single phase cabling, but your usage may be metered with error. my old house use to run 2 x 2hp, 1x 1.5 and another 1 hp unit but just for few hrs its still ok on single phase. But no doubt 3 phase is way forward for any future upgrade. Jus a humble opinion

Circuit breaker can tahan

But cables can or not

Later bakar

Take a photo of the meter, see how many cables are going in.

To tell whether one phase or three phase.

my friend house run 4 (2 2hp 2 1hp) on a single phase with almost 24/7 operation. the whole DB box on fire.

Sorry this question may be out of topic...how much to upgrade from single phase to 3 phase?need to call tnb to do that?

there is no barang elektrik that use 3phase...

if a house use 3phase it will split trough the house... 1phase max 4ac with fride, etc...etc...

i know, my house use 3phase

Please see page 1 but after mechanical engineer will come ketuk you .....say " what's wrong with one phase?"

This post has been edited by idoblu: Dec 26 2016, 09:53 AM

hmm...that must be a very big house that load exceed 50A

im no electrical engineer but i do a rough calculation. with the label on aircond compressor.

you need to run like duno how many aircond it only exceed 50A. base on 2HP AC

means his DB box there all those circuit breakers thing isn't rated for that high load

in constant high load that exceed the capability of the switch/breaker creates heat.

thats what happen to my house.

2nd it have nothing to do with single phase.

I got all 5 start same time no trip

1 phase 63 Amp is more than enough

Let anyone come ketuk lah.

easy to exceed for induction stove user. Example this 3zone hob consumes 32a peak.

http://www.hoekee.com.sg/p-1659-3zoneinduc...hobti1028b.html

paste sticker will do

Single phase 100amp can easily support 4 AC

But got money better over kill it with 3 phase since we do not know your actual usage or intended HP of AC

rite...now you are findding ways to exceed it

isn't normal household single phase is about 63amps?

just have a check on my house safety switch and is rated 63amps

my record were

2 x 1.5hp and 2 x 1hp running at the same time + on heater for 15minutes.

plus some gadget charging and my desktop

eh bro, what's the different between 3 phase and single phase?

Yeah, usual is single phase 60amp

But now got single phase 100amp

Mine is 100amp, single phase.

AC 6 biji all ok.

breakdown assuming using Acson aircond (the booklet just beside me).

1HP = running Amp = 4A
1.5HP = running Amp = 6A
2 HP = running Amp = 10A

total aircond running Current = 26A.

if you factor in fridge, cooker, iron, water heater confirm around 15A. very high possibility will trip if you currently on 40A main breaker

Your breaker size if 40A, then recommended to change to 3 phase 400V. (overall cost confirm more than 3k cause you need to change the whole incoming wiring and pay expensive fee to TNB for upgrading)

NOT RECOMMENDED TO CHANGE TO 60A Single phase breaker unless you double cheek the cable size is sufficient. ( I know some contractor especially aircond will ask you do like this but better not to take the risk)

If your breaker is currently using 60A SP. then should be sufficient

total 6HP =5kW

3 phase 60A and 1 Phase 60A have big difference bro

3 Phase 60A can take in at least double the electrical load

This post has been edited by squarepilot: Dec 26 2016, 11:02 PM

depends. some use 40Amp breaker.

those using 100A single phase breaker is bull shit. TNB where got 100A SP Meter? Max they give you is 60A SP meter only. 3 phase 100 CT meter got la

This.



Only bungalow/semi D need 3 phase for future proof.

Impressive 3 stove switched on at the same time.

careful on that. if TS using 40A breaker size i can confirm GG will trip anytime.

60A should be no problem.

This!

It is the cables that will burn and create fire hazards.

Yes, can support 4 x 2hp aircond but what else is in the house?

It is cheaper to upgrade or get proper electrician to check on the wires and loading then burn the home down.

Assume in total you have 6HP of airconds after adding the new unit.

rule of thumb for aircond power is 1 HP = ~753W

6HP x 753W / (240 V x 0.85 power factor ) = ~22.14 A

So you will have 22.14 A running in total just for the aircond, fridge, PC, TV, smartphone charger etc consume very little power, i assume all turn on together will consume a maximum of 5A, heater will normally consume 9A.

So everything in total will be 22A + 5A + 9A = 36A, so theoretically it should be safe. Aircond compressor / motor is theoretically to spike in initial start up for up to 6 times the normal usage so try to keep your total usage at around 50% of the total supply.

1 thing you have to take note is, your new 2 HP aircond power MUST draw power from new MCBs or that particular power circuit must consume very little power. for this you have to ask the electrician or the aircond guy to do it already.

You can see from your picture there are alot of small small MCBs, lets say there are 20 small MCBs, therefore your DB has 20 power circuits, you should have some spare unused ones, ask the electrician to pull cable and connect to the spare unused 1 and draw power from that spare MCB.

ok got it thanks guise

Our loads are all single phase. Very rarely you will have 3 phase air con for residential.

Let's say we 1ph.
Means 63A max like someone said.
(Also depending on cable sizing they did when they wire the house)

If you have 3ph, u theoretically can have 3x the loads.
This means that 63A x 3 = 189A total since what they do is they alternate the loads on 3 diff Electrical lines.

Is like having a 1 lane road vs a 3 lane highway.

But current always flow 2 ways. The neutral line have to be oversized properly too. So in the end might not be 3x max.

ok..

3 phase supply properly balanced across each phase means no current flows through the Neutral.. The neutral only returns the unbalance current across the phases..

11KV transmission lines is only 3 wires.. It is distributed in Delta with all phase current balanced.. Only when step down by transformer from Delta 11kV/433V Star is where the neutral is introduced where the Neutral is earthed..

From Transformer it goes to a Feeder pillar where there will be an Earth fault protection device before it gets distributed to residential properties where is must also be earthed at the DB.. This is known as a T-T (Terra-Terra) system..

The usual tail into a residential landed property is only 2x25mm(60A) or 2x16mm2(40A) Aluminium cable which only provides you the fuse rated max demand load which is a slow blow high rupture capacity fuse..

This maximum demand can easily be exceeded by the high inrush starting current of inductive motors (your aircon motor)..

3 Phase is the name of an electrical supply.. It can be 3 wire (2 phase lines plus Neutral) or 4 wire (3 Phase lines Plus Neutral) supply..

Single Phase is the name of a electricity supply of a 2 wire (one phase plus Neutral) supply..

If in doubt please get a competent electrical contractor to verify the existing maximum demand to check that your wiring can handle the electrical load..

You can easily overload (think electrical fire) your existing wiring if you change your protection fuse to a higher rating without knowing your maximum demand..

What I am saying is basic electrical common knowledge to all electricians..

If you don't understand what I'm saying please talk to an electrical person who knows something about maximum demand and how to use a clamp on ammeter..

Electricity is not your friend .. It is a known killer held in a copper prison just waiting to kill you..

oh come on, i was running 2KW server (4 GPU each server 950W power draw x 2) thro a 13A extension cord for 2 months 24/7. also use power meter to check.
dont simply scare monger la. use science to count how many Amp per 1HP aircon.. 40amps is alot for 240V, thats nearly 10KW of power.
as long as each 1HP aircon is on one electrical branch it should be ok.
only downside to my extensive server usage was my TNB was over 1.5k per month that two months..

thats why electical and electronics ppl are 2 different breed.
this is not 80s era aircon le.
nowadays all soft start and what not.

Careful ts.... better don't
If u wan to try

Pls remove all the plug first

er, you dont run 4 aircons on one branch of the mcb le.. that might be a cause of wire overloading.

^ mechanical engineer lai liao

one of my friends' house has 6 units of aircon..no issue

You understand .. but no one knows if he has an inverter unit or a conventional DOL start and that pictures shows a DB with 24 SP mcb's single phase..

I have never seen a single phase DB with so many mcb's..

Add to the fact they're all non branded components easily means if that RCD is defective any surge inrush current from a DOL motor will fuse any of those mcbs short circuit and start an electrical fire..

And it's not all soft start.. There's definitely more conventional DOL AC motors out there than inverters..

true, inverter is safer, on this issue.

but also for basic units that is not 20years old,
the compressor motor drive circuits also got ICs, current limiters and various diodes le.

and! when you turn on the aircon, the compressor dont kick in immediately.. its usually 5-10 seconds later than the blower unit starts to run.. and for that 0.1 second during motor start you dont draw 10amps and blow everything on your drive circuit PCB!

When I cook, I got use three stove at once. Multi tasking. But using gas stove la. Hahah

er...those soft start u mention does it applies to newer non-inverter AC?

but then....AC is a very long lasting thing. my house still got NATIONAL name tag AC

sure, refer to my answer above.. compressor kick in later.

anyway if you have 4-5 units of NATIONAL aircon, perhaps you wanna upgrade them to more efficient and higher EER or BTU rating.. 1HP aircon now 800-900 can get liao..got brand ones.

add another breaker laa... 20A rating

well.. is only 1 unit and that 1 unit is in guest room

rarely switch on 1 so....ok loh dint touch

I've been using 4 inverter ac (1x2hp & 3 x 1hp) for the past 4 years. No issue except have to pay a lot to TNB Just make sure it's connected from different MCB.

No sign of wiring overheating or what so ever. (Checked with FLIR thermal camera)

fuyoh use FLIR for hotspots summore..

Borrow from my brother. His company have some project with TNB that uses FLIR.

So far, everything normal. No sign of wiring overheating even though 4 ac are on simultaneously.

And I use this to check each AC current / load. All good

I'm not worried about lighting load as 100% LED light use throughout my house. Too little load.

This post has been edited by haturaya: Dec 26 2016, 10:34 PM

We're not talking about a single unit compressor.. The issue is maximum demand..

The maximum current load as in he already running 3 of his existing aircons couple that to the existing running load (refrigerator, lights, sockets, etc) and now his compressor kicks in..

This transient inrush will cause arching to the mcb's contact points..

It doesn't have to happen immediately when the contacts are still new or the spring tension is still good.. This will continue until a weak link in that electrical system fails..

You are an intelligent person.. What would your advice be to this situation?

use original european brand MCB!. all the concerns you mention are valid ...and using original branded components should perform at rated spec over time.

yes i got exactly this lelong unit.. haha

am surprised 1HP aircon doesnt draw much energy if you set temp at 26-27C compared to 20-22C range!

Yup, setting temperature plays big role too. As for me, 24-25C is the sweet spot. Comfy, not too cold, not too warm. Just nice. 3 bedroom ac 9pm till 6am daily. Monthly TNB bill between RM270 (rainy season) - RM350 (hot / dry season)

This post has been edited by haturaya: Dec 26 2016, 10:41 PM

wah...ni next level

thermal camera also come out
but2....26 ~27 macam langsung tak sejuk bang

just giving a bigger contrast in power consumption between the 2 settings. but as mention above 24-25c is ok, compressor dont kick in so often too which might draw more current and bigger tnb bill.

Borrow from my brother. Can't afford to buy one. FLIR super expensive.

Try not to use thick blanket. Just thin blanket will do. 24-25C is nice setting. Also depends on the room. Make sure no gap that cold air can 'escape'

40A as main breaker Tnb incoming size. Branch MCB is rated 15a for old ones and 20/30a for newer MCB.

I already calculate on my previous post nicely in my previous reply to TS. You can counter check if there is any problem.

He wants to add additional 2 hp. That's my main concern

This post has been edited by squarepilot: Dec 26 2016, 11:02 PM

4 aircond? Can no problem. But is it same time using all of the aircond?

hahaha ok la

no money to ensure no gap now

do you mind to elaborate on the "3 phase power equipment".. what are the things that needed for 3 phase? thanks in advance... im noob in electrical..

u mean a DB with 24 SP mcbs is pretty rare ah? is that mean install another aircond sure got no problem? my DB can handle it?

my house 1 phase 7 aircons + autogate. still alive here. true story.

I suppose so but difficult to isolate if there's a problem ..

The standard practice is to split the load into 2 DB's zones both with a DP RCD protection..

Example :
1.

Say you have a double storey house.. Bottom is one primary DB and 1st floor the Secondary DB

KWH meter to 40A DP (double pole) Isolator split to two 40A DP RCD's (two DB's) with 14 Way outgoing mcb's each..

That way if there's a fault its easier to identify problem mcb circuit..

It's also easier to ammeter clamp on to check the maximum demand current at a time everyone is home kitchen cooking, hot water shower and living room ac on at the same time ..

The peak maximum demand bell curve is usually at around 7am and 7pm for residential..

2.

Another way if it's a single storey is to zone the house into front and back areas and rearrange the wiring accordingly..

Seeing that you already have so many circuits its actually very simple to identify lighting and power ....

Then divide into separate zones and DB .. Both DB's can be next to each other but independently isolated in case of a fault..

Wow ur electricity bill one mo th how much bro