Got it.Thanks for the explanation with the picture man

Quick question. According to the wireman the RCCB can be fed from both ways, Is the Live & Neutral position correct? New RCCB ABB Model FH202 & MCB SH201L.

I also have many of the old MCB ABB Model S231. Can i mix and use back?
Thanks

Attached picture below


Attached thumbnail(s)

Yes the FH202 terminals are bidirectional from the diagram 1/2 2/1

SH201 without L better.

Old MCB u need to check for fakes as well. Since new MCB not expensive rm 8 a piece I would go for new “peace of mind” for 30 years

Thanks for reply. Mine all the new one SH201L. What is the difference with L and without ya?

Ok .will change all to new mcb

4.5kA vs 6kA short circuit withstand.

Meaning? Which is which ?
Sorry ya, i noob to this. Worried get con by wireman.:{

By the way the RCCB L & N in correct position right? Also the MCB load at bottom correct?

Thanks a bunch

Yes FH202 L&N ok one.

Traditionally MCB is line at bottom but ABB one bidirectional. Ok.

your pic shouldn't the wire be 16mm coming out from the main switch ? ? rather than 10mm ?
or cause you have 40a/30ma rccd thats why you ok with 10mm ?

i think he got another 100mA rccd on the upper part for the socket outlets, there's another 10mm cable going up there

Have 3 RCCBs

100mA for lightings
30mA for sockets
10mA for direct water related product (water heater)

my concern isnt the rccb or the xxmA , its more about the wire size /carrying amps and the sub switch lower amps

You are right, and that is an extremely valid question. Kudos for noticing that.

An RCCB, although marked 40A 30mA DOES NOT TRIP on 40A overcurrent. Ideally, the 10mm² wire would enter a 2 pole MCB rated 40A, and then only to the RCCB. This means there is overcurrent protection (MCB) and also leakage protection (RCCB) The wires are also protected, because the MCB will trip at 40A before the wires have a chance to heat up and melt.

But this makes the DB become very big. If I were doing the wiring, I would explain all this to the homeowner.

So why did I let this "fault" go without mention? It is because the 10mm² wire is still "safe" from melting no matter what happens. The INDIVIDUAL MCBs in the DB will trip if there is a fault (6A, 16A, 20A as in the poster's drawing) The 10mm² wire will never experience a 40A current unless the fault is within the DB itself, but this is very, very unlikely to happen.

Edit to add: Of course if you change all the 10mm² to 16mm², and the main RCCBs to 63A xxmA, you don't have to worry about any of the above. But you are now dealing with 16mm² wires within the DB, and that is a whole other issue

This post has been edited by stormer.lyn: Oct 12 2023, 09:01 PM

how fat is a 16mm vs a 10mm actually , the diameter ? until well you not wanting to deal with 16mm wire?

ps how u do the mm square thinggy ?

Because the OP is stuffing 2 sets of wires into the 63A MCB, and if they are trouble if they are 16mm². Part of the problem is that all electrical wires have 7 strands. They are small when the wire is 2.5mm², but each strand in 16mm² wire is relatively huge, and thus hard to bend and shape. Not impossible, just troublesome. And then finally you will realise you should have used a larger DB!

Your keyboard must have a separate keypad. Press and hold Alt then 0, 1, 7, 8 on the keypad. Technical person, so below are my most used symbols



For manual usage in this forum you can use the superscript tags

okie thanks for the sharing so the op, will be doing the electrical db sendiri or what ? since sharing the diagram pigue my interest is this gonna be a DIY or hire someone to do ?

My understanding is, the 10mm2 cable is ok since TS is not expecting the current over this circuit to exceed this, but TS need to install a 40A MCB before the 40A RCCD. To me this is a must, else you are right that the cable should then be 16mm2.

doesnt the 40A rccd also functions like a MCB ?

I don't think so, RCCDs are only for leakages/imbalance load. you will need a RCBO to cover the overcurrent protection. That's what i see in my current DB also, there's this extra MCB before the RCCD.

But I'm not an electrical engineer, so pls correct me if I'm wrong




Attached thumbnail(s)

https://chintglobal.com/blog/difference-bet...-rcd-rccb-rcbo/



MCB
MCB stands for Miniature Circuit Breakers.

MCCB
On the other hand, MCCB is an abbreviation for Molded Case Circuit Breaker.

RCCB
RCCB stands for Residual Current Circuit Breaker. RCCB is also known as RCB or RCD. RCD stands for Residual Current Device, while RCB stands for Residual Current Breaker. RCCB is an electrical wiring device that disconnects the circuit as soon as it detects a current leak to the earth wire. It also protects against electric electrocution or shock caused by direct contact.

RCBO and RCCBs, are residual current protection devices. This protection is achieved by monitoring the current flow in the line and neutral. In a healthy circuit, the current flow via the line equals the return flow in the neutral.

However, this return flow may not be equal to the line’s current flow in the event of any abnormalities. A residual current device will sense such a scenario and interrupt the circuit.

RCBO
RCBO stands for Residual Current Breaker with Over-Current. The RCBO combines the functionality of an MCB and RCD/RCCB. When there is a current leakage, the RCBO trips the entire circuit. Consequently, internal magnetic/thermal circuit breaker components can trip the electronic device when the circuit is overloaded.




so RCBO is better than RCCB, since RCBO can do both ?

This post has been edited by JinXXX: Oct 13 2023, 11:14 AM