Started 2 days ago to notice a weird smell in the house at night.
Only just now realized it came from the home electrical panel box. Felt the plastic panel box and it is warm to the touch. The smell must be slow heat against plastic.

I removed the screws and cover . And I could hear the scary electric crackling sound mildly. I have off as much power point as I can at this time of the night.

Anyone can recommend a qualified electrician around Sri damansara area? Much appreciated.

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This post has been edited by pmaxv: Dec 31 2019, 01:21 AM

Eek. That's a good step which you have done. Now is finding the right guy to investigate the issue. Could be wire or fuse problem.

Ur home alot of ac? Sounds like the wiring system cant support ur load

The smell started only 2 days ago. House has only 2 ac (1.5 hp and 1 hp). Nothing new was installed lately, except a Xmas tree with lights, I have turned it off .

Yes, I need a good electrician to look into it asap tmr.

The fuse (?) with the 60A word is a little warm to the touch.

Looks like both of that need to be changed. 60A and the N one. xD See the bottom there looks a bit fat already. xD

Any idea why it decides to give way? The load has remained more or less the same for many years. But Yes they are as old as the house , more then 20 years.

It is probably the bad contact between fuse and clip or wire to the connector.

When the contact is loose, it creates resistance and gets hot when large current flows through. And when continue in such condition, spark jump from contact to wire. That it where the sound come from.

Go to any electrical shop around your area. Those selling electrical parts like wire, mcb etc. Ask the boss some electrician contact.

Don't change back to fuse type. Ask the electrician change it to MCB 60A.

And ask him to check all the wire secure screw tight to mcb, rccb etc in the box.

Most likely its the quality they used, as you said you stay in Sri Damansara area and I'm assuming Bandar Sri Damansara, so the area is quite new, i mean compared to SS2 and areas nearby there, and also there seem not to have a brand on it. Usually there will be brands like EPS, Scheinder etc. Sometimes these things we cant tell, even some branded ones will have some faulty units.

Just to update. Electrician is here and found the problem as suspected.

AC, Dryer, Water heater, electric stove and vacuum all these are high drain appliances, if two or 3 switch on concurrent it may cause this issue especially when the connection are loose.

Shouldn’t the fuse blow when this happen ?

Yeah but the problem could be defective wiring or connections which dont create overcurrent (fuse protect overcurrent); fuse also got slow burn type which means if u load a 60A for very short period beyond 60A it will not burn instantly/trip like a mcb.

Best is to change the whole thing to a proper set of MCB/RCCD/main isolator/RCD 10ma for water heater.

Branded ones will keep quality better. Minimum also get schneider, ABB or hager. Not that expensive la.. but best to get all in a series if possible. Cheapo MCB tarak quality one.

Basically the proper setup will be
[optional] main switch isolator
63A RCCD, 30ma recommended for safety. 100ma of 240V can cause alot of human damage. The lesser current leak thru human the safer.
63A MCB/MCCB (1phase / 3phases)
then individual MCB - typically C20 (20A) for 13A sockets, aircon, then C6 for lighting.
If u wanna further protect get a B16 or B20 (20A but B-curve) MCB exclusive for water heater circuit + 10ma RCCD. WH must have an MCB + 10ma RCCD.
Outdoor circuit (external sockets that can get wet), autogate, ding dong bell, ideally also should be protected with 10ma RCCD.

This post has been edited by ceo684: Jan 2 2020, 01:15 AM

The current doesn't reach over 60A.

This wire can stand over 70A before it melts down.

How much kena charged?

Hi bro, you seem quite well versed in the electrical field. May I ask if you are an electrician? hehe. xD I only know so far about Distribution boards and types of MCB, for lighting, for sockets and AC, heater. But not sure about B16 or B20 MCBs as I have not encountered it before.

Nope not an electrician by profession, but I did sell MCBs, motors, inverters and related automation controls (sensors, PLCs) before many years back.

DB box, matter of affordability for consumer grade units. Best is to go for metal clad boxes (can even find Eaton ones on shopee ), but any decent one will work.
Metal > PVC for flame retardant properties.

Basically the idea is that the MCB is supposed to sacrifice itself way before the wires overheat as that can cause a fire and extensive damage (imagine running new cables need to hack and replace everything). Hence I believe in properly sizing the MCB according to the load i.e. not putting an excessively large MCB for a given load (next size up is best). In my case, my place they put in a C10 (10A) MCB to protect a few lighting points which is rather overkill (even if you use all conventional fluorescent light which has initial spike when starting), it will not overload a C6 or even a 3A MCB. I also need to balance cost/sizing because other than the normal C6/10/16/20 MCBs its hard to get the other sizes affordably in MY.

WH (water heater) has ST special guidelines issued that you must protect areas with wet floor with 10ma RCCD - this will protect current imbalance only (i.e. input L and return output N must equal current else something has leaked (better get decent ones from ABB/Hager/Schneider).
Note that RCCD only protect against imbalanced current only, it does NOT protect against current overload (wire protection).

Hence WH RCCD must be run together with a normal MCB (for current overload).

Why B curve instead of C curve for WH?
As WH's heater is a resistive load (i.e. uses resistive metal to generate heat) and not inductive (ie. no motor is involved) load, B curve MCB is better as they are more sensitive (trips at lower spike current) than a C curve MCB (which is essentially a general use one as things like aircon/vacuum cleaner are motor-based, so less nuisance tripping).

RS/element14 does sell Siemens B16 MCB Siemens B16 MCB which should work for most 3.3/3.6kw heater (3300/240=13.75A, mine ran at 13.2A on clamp meter test) (3600/240 = 15A which is cutting it a bit close but still possible to use on 16A MCB). If you have very strong water pressure and using those 4.8kw models from hitachi you are running 20A nominal so a 20A would not be enough, probably a B25/C25 can be used (https://new.abb.com/products/2CDS211001R0254/miniature-circuit-breaker-sh200-1p-c-25-ampere).

https://cache.industry.siemens.com/dl/files...50852395217.pdf
see page 23. actually siemens recommends using B curve for universal use (socket outlets and lighting circuits) vs MY general practice to use C curve for everything

https://www.se.com/au/en/faqs/FA290880/
even SE also recommends B curve for residential use.

What is B- or C- curve
https://www.se.com/in/en/faqs/FA228794/ and
https://library.e.abb.com/public/e39a8392ab...403003B0202.pdf
see page 7 trip curve info for diff between B/C/D curve

https://library.e.abb.com/public/114371fcc8...2D0201_view.pdf
see page 3, trip curve characteristics for inrush (spike) current. this means B spike is 3-5x rated current before tripping, C spike is 5-10x rated current before tripping.

This post has been edited by ceo684: Jan 2 2020, 01:58 PM

Oh wow. That is so detailed. I will search more on the B curve MCBs. Haha. Because usually I allow 1 20A MCB for AC and 1 20A MCB for water heater. And I usually use C10 MCBs for lights. Maybe I will switch to C6. 😅😅