Anyone knows how to size MCB of our home?

Got B,C,D type and different Amperage. How and what to choose?

Bro, if you are not sure please get engage the help from a professional electrician. In the event of overload, fire may occur thus handle with care.

This post has been edited by Xccess: Oct 9 2013, 02:40 PM

varies on electrical appliances, lights usually fitted with 6 ~ 10A, airconditioner and fridge to 30A ...

Common is 6, 10, and 15.

30A make sure you have thick cables minimal 4mm.

How to know 4mm, xmm? Some cable got 3 wires, some 1 wire, etc.

What mm for which Am rating?

Thanks

Actually, why do you post this question?

My house MCB most of it harden already, stuck, so difficult to pull down or push up. My electrician advised me to change all even though some are still good. And he suggested all change to 32A. I have 10, 20 and 32A. I am worry about his advice to change all to 32a and if the cable/wire can take load and what is the danger of doing so.

It is time to get some advice from others like you and be sure and if I can diy or just let him do it. See picture of my DB and the 3 types of MCB.

all change to 32? what for

if the device only suppose to run 5A, and connect to a 8A breaker. anything more than 8 it will trip to protect the device

unless you expect it to shoot up to 32, no point to up the amp by so much. 100 percent still reasonable, few hundred

First thing you need to do is terminate your electrician....change all to 32A???


The big one with black handle is the Main Switch - If you ON/OFF this, it will ON/OFF whole house
The blue handle is the ELCB (Earth Leakage Circuit Breaker) - This is the protective device to protect your electrical system if there is a current leakage.
The other are MCB (Miniature Circuit Breaker) - This is the circuit breaker of each wiring circuit.

My suggestion....replace according to existing rating.....


This post has been edited by ezzone: Oct 9 2013, 10:58 PM

Your electrician want you to change house is it? All 32Amp, if wires are 1.5mm, use until wires burn the MCB won't trip. Usually they will put 20A for socket, and some will use 32A for a/c and heater, but 20A is good enough because 2.5mm can't supply 32A load for long period, and now a/c don't have such high spike.

Light, use back 6A or 10A.

Best check the old MCB, and do direct replace.

Thanks for the replies.

But the problem is few socket/power point to one MCB. So, if on all together total load could be more than 20A.

Let me check one by one and post here again.

This is not the original, he changed it 12 yrs ago when i reno my house so direct replace also may not be correct.

I will test out all how it is all connected how the MCB are shared and post the table here for your further advice. Now at night cannot test, cannot see in the dark.

Also, that is why i am asking about the wire, how to identify the wire rating.

This post has been edited by stevie8: Oct 9 2013, 11:04 PM

1) The solution to this particular problem is to add more MCB and split some of the socket to the extra MCB.

2) As others have mentioned using 32A MCB with writing only meant for 10, 15 or 20A MCB will lead to fire when there is an overload.

3) fire you electrician and get one that gives good advice.

Not easy to guide you identify wire type. Best go to the electric shop ask sample. Alternative, take out your power point faceplate see the wire, hope your contractor use the correct wire size.

If you share few load into one MCB and use over 15amp load, long run if the 2.5mm cable don't burn it will get harden and trip frequent because cable can be crack.

You better get a qualified electrician - make sure he is registered with TNB before you engage. Wire-cable thickness is very important ... if the load more than wire can handle then it will overload which leads to wire becomes heated up which leads to electrical fire.

Each wall power socket should not be more than 13A which means your fuse should be 15A. And depending on how your electrician wired up your sockets previously ... some electricians do short cut ... they put multiple wall socket on one wire example one room you ask 3 sockets ... that may be shared with 1 wire 1 MCB ... thus it is no better than an extension bar ... maximum load combined is only 13A.

Kitchen appliances such fridge, washing machines, microwave, electric stove, etc. usually will require its own dedicated socket and MCB ... that would be around 20A each. This especially true if you use very old appliances. New modern appliances nowadays use a lot smaller amps - so a standard 13A can support.

You better check your appliance power draw requirements and count ... to be safe make sure total amp to 1 wall socket is no more than 13A. If you are overloading ... you have inefficient electric wiring which leads to high power loss which leads to a higher power bill.

So when it comes to electric wiring ... don't play-play ... be penny wise pound foolish.

Hope that helps.

This post has been edited by amberglow: Oct 10 2013, 10:41 AM

Can you advise what mm wire is for what amp MCB?

Guys,

This is the power table of my house (see attached files).

As you can see from the picture post earlier, there is no more space for MCB, how to add?

Bro, a word of advice, please get the help of a certified electrician. I used to work as a electrician many years ago when I was much younger, even with a certain level of experience, I won't touch the electrical box let alone changing of ELCB and ECB.

Please take note there's live wire in it unless you shut off from the main electrical board outside your unit. Stay safe.

Lighting Load
6-10A (cable use 1.5mm)

Power Load
20A -30A (cable radial or ring circuit)