I requested for RCBO for my water heater, but this is the outcome, I'm trying to understand from the contractor but he say very complicated,explain also I don't know

What I see from here I FEEL it is very weird, the My kitchen hood and one of the aircond is connected to RCBO and 25A ELCB instead of water heater.

When I turn off or trip off the 25A ELCB with test button ,the power running for kitchen hood and one aircond , only turn off when I press test button on the RBCO or turn off the main switch. What actually went wrong?

*Typo, one is 63A , another is 40A ELCB, connected with RCBO one both is 25A









This post has been edited by Pain4UrsinZ: Aug 11 2023, 03:31 PM

It is hard to tell without onsite checking.

Why not just request the installer to come and check/test on site?

RCBO with sensitivity 10mA is for water heater. other appliances no need that sensitive RCBO. Aircon even higher at 100mA. This is all according to Suruhanjaya Tenaga guideline.

The 2 Himel 10ma RCCBs seems to be wired incorrectly and serve no purpose. It could be done so on purpose to bypass the RCCB by the contractor because there are shared neutrals between the circuits and they are too lazy to fix it. I doubt they are that retarded to so by mistake.

So they contractor not only bluff me about RCBO but also make my 10mA rccb become dummy? My water heater is now just connecting directly with MCB?

This post has been edited by Pain4UrsinZ: Aug 11 2023, 04:18 PM

From wat you explained, it looks like it.

Your simple test already determined your water heater not connected to the RCBO as it was not turned off.

Wouldn't it be more easy and straight forward for them to just connect the water heater to RCBO? Why they seems like put more effort to do so many pattern and bluff me?

This post has been edited by Pain4UrsinZ: Aug 11 2023, 05:14 PM

Wiring also blue color got neutral and life 🤦🏻‍♂️🤦🏻‍♂️🤦🏻‍♂️, correct way is mcb out to rcbo 10ma than rcbo to water heater

If the water heater is sharing neutral with other circuit (as in 2 MCB sharing same neutral cable), it will trip due to current imbalance if it is wired to the RCCB or RCBO normally.

To fix this usually have to pull 1 or 2 new cables depending on how it was 'shared' in the first place. If the water heater is under shared circuit, just pull new cables for L + N to water heater especially if it was smaller than 4mm². Just make sure the old cables dismantled properly and not exposed.

this is the original one before the contractor me to add more point and rcbo. originally 2 water heater are connecting to 2 separate elcb and mcb, can this prove that it is using differen neutral ?

If the original circuit has working RCCB + MCB for both waterheaters, it will also mean there is no shared neutral. There is absolutely no reason for it to be bypassed or wired incorrectly unless they mess up the original water heater circuit afterward. It could be as stupid as new ventilation fan neutral from the water heater and live from lighting or vice versa. Rather than guessing, it's better you ask the contractor to rectify it. If they really add more points looped from waterheater circuits just to save cost, fxxk 99 them.

This wiring is correct (.....well except for the 2.5 mm² wires used. Should be 4 mm²) with each Water Heater protected by an MCB (in case of shorting) and an RCCB (10 mA sensitivity, in case of current leakage)

Why did you install the additional RCBOs?

Simply because I heard RCBO better
Willing to spend money on this to make it safer then ppl just fkes it up

This post has been edited by Pain4UrsinZ: Aug 12 2023, 09:08 PM

Okay.

Your contractor has rewired it wrong. If you can, just replace the two 10 mA Himel RCCB with the Schneider RCBOs. All wiring the same as original and you should be good for the water heaters.
Both the Himel RCCBs have 2 in and 2 out wire connectors, as does the Schneider RCBOs. Swap 1-to-1, same hole to same hole - as per the original developer wiring

Actually it depends. Doesn't mean RCBO is better.
From the developer diagram, the MCB+ELCB (10mA) (i think is RCCB) is already following Suruhanjaya Tenaga guidelines and provided protection for overload + leakage current.
Use RCBO if only MCB is provided, then people replace the MCB with RCBO to provide 2in1 protection where there is no RCCB connected.

RCBO/RCD must have two cables on top and on bottom so it can operate. Yours is 1000% dummy and serves no purpose. Refer my pic the top right, far right RCD (the big block).
The RCD on the left not connected, that time didn’t install second WH yet, no moneh

In any case it should be double protection as in one mains 63A 30mA output (Load) to the 10mA input (Line), not line to line connection. The idiot who installed this don’t know what he/she is doing. Pls get a proper wireman certified with PW1/PW3 certification to make it good.


The WH RCBO/RCD supposed to be sub/final circuit not the main circuit (main power outlet). In this case shutting off the main RCD and MCB does not cut power to entire house since WH circuits are still hot. Pls bear in mind this is very dangerous ⚠️

This post has been edited by ceo684: Aug 14 2023, 08:27 PM

RCBO is compromise solution due to lack of space usually.
No harm keeping because 25A is ok for high quality 2.5mm2 cable like Mega Kabel but most of the time substandard cables tarak laser marking or embossing were developer installed so you have an idea how “good” lah, hence having 20A MCB for WH better (Derated for safety) which most RCBO is 25A which is kurang sesuai when used with substandard cable.

Because it is quite a frustrating job to identify the correct neutral if not setup correctly in the first place. They cut corners. Not to say impossible but they really not trained in electrical safety and/or “not my house syndrome”

I’m not in town, but you can contact En.Isa +60 11 5116 5849 if you’re kinda near Shah Alam, he also does good work

This post has been edited by ceo684: Aug 14 2023, 08:11 PM