Are circuit breakers enough to protect us against electric shock?

grenade0

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So I read somewhere that circuit breakers only provide protection to wires and home appliances and does not provide any protection to humans, And there is some other kind of circuit breaker called RCCB required for that purpose.
So can anyone please in simple terms explain what are these RCCB circuit breakers? are they necessary or the normal circuit breakers enough to protect humans? Is there any load limit to these RCCBS?
Thanks
 
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When you say circuit breakers, you probably mean MCBs. MCBs are like resettable fuses, they'll allow current passage up to a certain amount, then trip, depending on their config. MCBs are not likely to prevent electrocution, as the current limits are rather high (5Amps min for households), and the likelihood that you'll exceed that and the MCB will trip is quite low.

RCCBs on the other hand monitor both wires, phase and neutral, and will trip when the difference is as low as 20 milli-amps. The reason they're more effective is people get electrocuted by touching phase wire while connected to ground, far more often, as opposed to touching both phase and neutral. If a person gets electrocuted by phase and ground, there will be a current difference between phase and neutral, as instead of neutral the current is now passing through ground. This triggers the RCCB, and disconnects the line. Again, RCCBs aren't foolproof to my knowledge, as someone touching both phase and neutral may not trigger it, but they're far more effective against electrocution.
 
What most people don't know is, according to correct standard, if you are using inverter you are suppose to use second dedicated RCCB for it, your main RCCB gets bypassed when inverter connections are made.

So when you have power your main RCCB will work to protect you, in case main power goes out, the inverter turns on, then your second RCCB will protect you, in case you touch live and ground.
 
When you say circuit breakers, you probably mean MCBs. MCBs are like resettable fuses, they'll allow current passage up to a certain amount, then trip, depending on their config. MCBs are not likely to prevent electrocution, as the current limits are rather high (5Amps min for households), and the likelihood that you'll exceed that and the MCB will trip is quite low.

RCCBs on the other hand monitor both wires, phase and neutral, and will trip when the difference is as low as 20 milli-amps. The reason they're more effective is people get electrocuted by touching phase wire while connected to ground, far more often, as opposed to touching both phase and neutral. If a person gets electrocuted by phase and ground, there will be a current difference between phase and neutral, as instead of neutral the current is now passing through ground. This triggers the RCCB, and disconnects the line. Again, RCCBs aren't foolproof to my knowledge, as someone touching both phase and neutral may not trigger it, but they're far more effective against electrocution.
So The phase wire is the Red wire and the neutral wire is the Black wire. If I touch both the wires together, I will get electrocuted, given that I am touching the ground (Or will I still get electrocuted if I am not touching the ground?) And in this case the rccb will not protect me. The second case is when I am touching the red wire and in contact with the ground , I will get electrocuted if No rccb is installed. Right?
And can you please tell me do both phases pass through the same wire?
What most people don't know is, according to correct standard, if you are using inverter you are suppose to use second dedicated RCCB for it, your main RCCB gets bypassed when inverter connections are made.

So when you have power your main RCCB will work to protect you, in case main power goes out, the inverter turns on, then your second RCCB will protect you, in case you touch live and ground.
Do people generally install RCCBS? I don't think the person who did wiring in our house installed these RCCBS.
 
The phase wire is the Red wire and the neutral wire is the Black wire. If I touch both the wires together, I will get electrocuted, given that I am touching the ground (Or will I still get electrocuted if I am not touching the ground?) And in this case the rccb will not protect me.
If you somehow touch both the wires red and black without touching the ground, you will get electrocuted. RCCB can’t protect here.

But this scenario will never happen. Unless you are poking somewhere intentionally, where you shouldn't.

The second case is when I am touching the red wire and in contact with the ground , I will get electrocuted if No rccb is installed. Right?
Yes, if RCCB is not installed, you will get electrocuted.

Do people generally install RCCBS?
It is necessary.

I don't think the person who did wiring in our house installed these RCCB
How do you know?
 
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If you somehow touch both the wires red and black without touching the ground, you will get electrocuted. RCCB can’t protect here.

But this scenario will never happen. Unless you are poking somewhere intentionally, where you shouldn't.


Yes, if RCCB is not installed, you will get electrocuted.


It is necessary.


How do you know?
If you somehow touch both the wires red and black without touching the ground, you will get electrocuted. RCCB can’t protect here.

But this scenario will never happen. Unless you are poking somewhere intentionally, where you shouldn't.


Yes, if RCCB is not installed, you will get electrocuted.


It is necessary.


How do you know?
These are all the mcbs that are installed in the meter box. Do you see any rccb installed?
 

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As per my observations I don't particularly see in the images share the RCCB, they are regular MCBs with varying current capacity.
I have had various experience across India, not all electrician set these devices.
In some places they have RCCB (mounted close to main mcb devices), as soon it detect leakage current, like an issue with geyser it would trip the whole house main MCB.
 
As per my observations I don't particularly see in the images share the RCCB, they are regular MCBs with varying current capacity.
I have had various experience across India, not all electrician set these devices.
In some places they have RCCB (mounted close to main mcb devices), as soon it detect leakage current, like an issue with geyser it would trip the whole house main MCB.
Thanks for replying.
I have a few questions
Can we install it now and can a normal electrician install these?
And I have seen in News that some people get electrocuted from the water coming from the geyser, can these RCCBS protect against that issue too ?
 
Can we install it now and can a normal electrician install these?
Yes, it should be possible, but do have an extra space to mount these additional safety devices?
As per your images, I don't see any kind of space left to add additional devices.
I would recommend consulting with your electrician if you would need to replace some of the existing devices.
And I have seen in News that some people get electrocuted from the water coming from the geyser, can these RCCBS protect against that issue too ?
As far as I understand these devices do protect against electric power leakages in geyser.

I have limited experience using these. I had one event happen where the next floor neighbor had a pipe burst in the wall, which they were unaware.
When I tried switching on the geyser the main MCBs were tripped which was a bit surprising, tried enabling the power back on it immediately tripped again.
That's when I realized there was an electric power leakage even before the physical sign of water damage could be ascertained.
We immediately notified the neighbor to take action before further damage could occur.
 
These are all the mcbs that are installed in the meter box. Do you see any rccb installed?
Here is Photo of RCCB. The 2 in middle @ encircled are RCCBs.
Can we install it now and can a normal electrician install these?
Yes, You can get RCCB installed now. Get the electrician who did your MCB installation. After Installing RCCB, test its function by pressing the small button, it should trip the MCCB. Also get your earthing checked whether its upto specs and functioning properly.
 

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The circuit breakers come in many variations and RCCB is the most advanced one to protect you from leaking current. It also had an older version called ELCB which would break circuit if there was some issue with body of the applicance e.g. Fridge body leaking current, but RCCB is next evolution of it.
Here is a link for it https://cselectric.co.in/blog/difference-mcb-mccb-rccb-elcb/#:~:text=RCCB refers to ear stands,refers to current operated devices.
Isn't ELCB good enough? Or are you recommending replacing an ELCB with a RCCB
 
Isn't ELCB good enough?

FeatureELCB (Earth Leakage Circuit Breaker)RCCB (Residual Current Circuit Breaker)
TypeVoltage-basedCurrent-based
Working PrincipleDetects voltage on the earth wireDetects imbalance between live and neutral current
Wiring RequirementNeeds proper earthing connectionWorks even without earthing
AccuracyLess accurate; only trips if leakage flows through earth wireMore accurate; detects any leakage, regardless of path
InstallationObsolete in most modern setupsStandard in modern Indian homes
SafetyNot effective if earth wire is brokenSafer and more reliable
Response TimeSlowerFaster (typically under 30 ms)

ELCBs are largely outdated and less reliable for today's electrical systems.
 
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Isn't ELCB good enough? Or are you recommending replacing an ELCB with a RCCB
From what i have read and learnt (not an electrical engg) - ELCB required proper working Earthing to work, essentially lets body current in appliances pass through the earthing. MCCB works on Phase and Neutral, if it senses voltage difference between the 2 of over 30mV it shuts down power supply (trips). It works even when Earthing is not perfect or broken. Electrical Engg FMs can confirm and eloborate further.
 
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This is surprising for me, my house is very old, built in the 90s, and it has RCCB from the beginning, I thought it's mandatory in building code, but turns out it isn't.