A few questions about RCD

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SUMMARY

The discussion centers on the functionality of Residual Current Devices (RCDs) in two scenarios: connecting a 2kW heater to an external RCD using hot and neutral wires from a 230V AC socket, and using an AC floating supply instead of the standard hot and neutral wires. In both cases, the RCD will trip if there is a current imbalance, as it detects differences in the currents passing through its transformer core. This is due to the principle that equal and opposite currents cancel each other out, and any leakage fault will result in a secondary current that triggers the RCD.

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gen x
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1) If I take hot and neutral wire from 230V AC socket and connect to external RCD that has one wire parallel to it, and connect to 2kW heater, will this RCD trip?

2) Will RCD trip if this is AC floating supply instead hot and neutral wire?

I interested will one wire parallel to RCD couse current imbalance inside RCD...

d.webp
 
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Yes it will trip.
 
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In an RCD, the circuit wires pass the same way through a transformer core. If the currents are equal and opposite, their magnetic fields will cancel, so there will be no secondary current. A leakage fault to another circuit or earth, will cause a small secondary current, that will trip the RCD breaker.
 
gen x said:
2) Will RCD trip if this is AC floating supply instead hot and neutral wire?
Yes.
If there is a difference in the two circuit currents that pass through the RCD, then it will trip.
 
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After all the other discussion in the other thread(s), how could you not realize this?
 
Causing an internal bypass inside the RCD is how they are tested. Pushing the test button does something similar to what you describe.
 
Averagesupernova said:
After all the other discussion in the other thread(s), how could you not realize this?
To me,it is crystally clear that will trip, but members with highest reputation scores at stack exchange, tell that RCD will not trip, so I check here..
I will not write a link because you already told me that you dont comment other opinnions..
 
gen x said:
I will not write a link because you already told me that you dont comment other opinnions..
I did not say that. I said I will not continue to chase endless links that you provide in an attempt to support your incorrect position. If I didn't comment on other opinions then why would I have posted on your opinions? If you post the link to stack exchange I will look.
 
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Averagesupernova said:
I did not say that. I said I will not continue to chase endless links that you provide in an attempt to support your incorrect position. If I didn't comment on other opinions then why would I have posted on your opinions? If you post the link to stack exchange I will look.
in comments members transistor and andy aka write rcd will not trip, because there is no current leak to the earth... I dont understand their logic at all..


https://electronics.stackexchange.c...ring-fault?noredirect=1#comment2028722_763901



https://electronics.stackexchange.c...on-in-home-electrical-system-really-necessary
 
  • #11
Ok so this is just more regurgitation of your previous thread. Are you Elizabeth in the stack exchange thread? It seems Elizabeth has the same tendencies that you do by asking the same question over again and in separate threads. This image and variations of it continue to pop up here on PF as well as your links:

Captur1e.webp
As drawn the RCD will trip due to the perceived connection between the red wire and the chassis of the receptacle that the appliance is plugged into.
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The RCD will not trip if the green wire between earth and the neutral is removed. This is clearly shown in another similar image. This is all fine and well but that is not what your diagram in post #1 of this thread shows.
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So what does one thing have to do with another?
 
  • #12
  • #13
Which is case #2? Specifics please.
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I will again state that the scenarios in the links you have provided so far do not relate to the diagram you posted in the first post of this thread well enough to provide an intelligent answer. You are expecting the same yes or no answer for different questions.
 
  • #14
Averagesupernova said:
Which is case #2? Specifics please.
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I will again state that the scenarios in the links you have provided so far do not relate to the diagram you posted in the first post of this thread well enough to provide an intelligent answer. You are expecting the same yes or no answer for different questions.
case 2 in this link,

https://electronics.stackexchange.c...ring-fault?noredirect=1#comment2028722_763901
 
  • #15
Ok what you refer to as case #2 has the conduit/protective earth conductor/chassis tied to neutral, but no electrode driven into the ground. It will trip as drawn.
 

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