It’s for lighting only (does not control any sockets or any water heaters) then it’s ok-lah

Six times ded. Hexa kill 300mA is only used in commercial/industrial applications. You don’t run huge motors at home

If your final circuit have 30ma then is ok

Else die also won't trip

For a 3-phase supply, yes it is OK. But if you have instant/storage heater, run a different RCCB of 10mA (either 16A or 20A) for best protection.
For my own home I have individual RCCB for:

1) Power Circuit (63A 100mA)
2) Lighting Circuit (25A 30mA)
3) Solar Heater Circuit (16A 10mA)

Mine is on single phase setup.

My friend told me the same to ass individual 10mA for water heater.

Got it. will change it to 100mA then.

Use 30mA, no developed country use 100mA for homes one.

Got it... Will do so....thanks for the guidance...

why many still using ELCB instead of RCD when RCD is better and cheaper cost ?

ELCB is cheaper because it is dinosaur tech.
https://electrical-engineering-portal.com/w...rent-device-rcd

10mA RCD one ketul good one (ABB/Hager) VI type already RM160 barang only.
It attract new problem like no space in DB box and a complete overhaul of new panel (new DB) is a lot of work and not every customer willing to pay for it.
Quote even RM10 more expensive you lost the job so there is no incentive to do things proper in MY.

This post has been edited by ceo684: May 8 2023, 02:55 PM

Actually most RCCB on local market is VI type, even the 10ma local branded China oem design. Only RCBO some is VI type. You can check on the diagram on the RCD. You can even test trip VI RCD using 1.5v battery, some will trip instantly & others will trip after current flow both direction once.

ST guidelines and electrical safety guidelines say max sensitivity is 100mA for both 1P and 3P supplies.
For 3P, you can choose to install one 100mA rccb (if any phase is defective, you lose power to whole house) or 3x100mA rccb for each phase.

https://www.clipsal.com/learn-and-discover/...ts-up-buzz-rcds
In Australia:
The main change is to the application of RCDs in domestic installations. All final sub-circuits in a residential installation, no matter the amperage or number of phases, are to be 30mA RCD protected. In general, the changes made now require fixed or stationary electrical equipment, such as a hot water service, an air conditioner, cook top, oven or range to be protected by a 30mA RCD.

Where a whole switchboard is being upgraded to replace existing protection then that switchboard is to be brought up to date with RCD protection.

In Msia:
Maybe humans in MY can tahan better than humans in AU.

Yeah, ST still allows 100mA for lighting and AC.

House developers will always say if you use 30mA as main RCD, you can expect trips every 2-3 days.

Didn't see my own place blackout every 2-3days its a myth

That's a dilemma I'm facing. My house has just one main 300mA RCCB.
Really confused now with the options:
1) one main 30mA rccb and 10mA rccb for heater, but worried about frequent trips as double storey house tends to have more current imbalance due to more circuits/fixtures?

2) 100mA main rccb, 10mA rccb for WH, and swap SSO circuit MCBs with RCBOs - means aircon and lighting circuit protected by syok-sendiri 100mA main rccb.

Which option should I go for?

Also, will adding SPD at DB help with trip reduction especially during thunderstorm?

1. Modern 30mA = Never tripped except for severe thunderstorm (wind howling type). Maybe once/twice a year at most, not every single rain like the old 300mA we had.
Whole SG also using 30mA don't see blackout all the time.

2. Very costly. For what follow ER1994 spec identically when we can go tighter without problems.

Just don't cheap out on RCD can liao. Get ABB/Hager (with anti nuisance trip)

This post has been edited by ceo684: May 12 2023, 08:51 AM

I'm leaning towards a main 30mA RCCB due to it being safer for the whole house and cheaper too.

When you said anti-nuisance, are you implying there are versions with or without this feature, or in general ABB/Hager has better anti-nuisance feature compared to other brands?
Asking because I checked with Shopee ABB official store seller, and they told me the model I'm interested doesn't have anti-nuisance trip feature.

https://shopee.com.my/ABB-RCCB-ELCB-FH204-A...8d-a9aef9a044be

They suggested adding auto recloser (almost RM1k), which could be my Plan B.

TIA

Most electricians/shops in malaysia that sells these items do not understand the actual use of it, or how to properly use it.

Only use the 30mA RCCB for single water heater, not for the whole house. Read this for more info : https://www.st.gov.my/en/contents/presentat...cal%20insta.pdf

This post has been edited by jex-koi: May 14 2023, 09:12 PM

I don't understand this statement.