AC connection on single point RCD/GFI breaker

[VocalNeal 7,275]

AC is not my strong point.

On all connection diagrams I found on Interweb they show black incoming connected to black outgoing and white connected to white. 

My house wiring at that location has white to black and black to white.

Surely with AC they flip at 50 hz. so "polarity" shouldn't be an issue.

So is it crucial. To correct I have to take the mount off the wall etc. and reverse the holes that the wires protrude from.

[sometimewoodworker 3,060]

51 minutes ago, VocalNeal said:

On all connection diagrams I found on Interweb they show black incoming connected to black outgoing and white connected to white. 

My house wiring at that location has white to black and black to white.

Surely with AC they flip at 50 hz. so "polarity" shouldn't be an issue.

So is it crucial. To correct I have to take the mount off the wall etc. and reverse the holes that the wires protrude from.

Just swapping so the colours match may not be a good idea.

 

checking that line is black and neutral is white is a good first step.

 

if you just reverse the connection you could well end up switching neutral not line, so allowing for entertaining dancing when you accidentally make contact with a live part that is switched off so should be dead.

 

There isn’t polarity on AC but there is line (usually at about 220v to earth) and neutral (usually at about 0v to earth).

 

Holding a neutral with a sweaty hand with sweaty feet on a damp floor certainly isn’t recommended but usually doesn’t do anything.

 

Holding a live line with a sweaty hand with sweaty feet on a damp floor can be everything from entertainment for onlookers to deep sadness that they have to deal with hospitals, embassies, temples and spending money on a “he’s dead” party.

 

is it crucial to correct? No. Is it important to correct? Quite possibly.

is it as simple as swapping wires? That depends on your desire for the real possibility of a shocking experience.   But no it isn’t without checking everything else first.

[VocalNeal 7,275]

But does the RCCD device know which is Line or Neutral?

 

There is no terminal designation on the device.

 

It trips when the test button is pressed.

Edited September 30, 2020 by VocalNeal

[sometimewoodworker 3,060]

11 minutes ago, VocalNeal said:

But does the RCCD device know which is Line or Neutral?

For an RCCD with no markings for line/neutral probably not. But some do need to be wired correctly to function, they should be/are marked.

 

The way an RCCD disconnects is important. If both L/N are disconnected it probably makes no difference. If just 1 gets switched then it is rather important that it’s Line, at least I think so.  
 

I’m sure @Crossy will correct me soon if I’m wrong.  

Edited September 30, 2020 by sometimewoodworker

[bankruatsteve 1,805]

12 minutes ago, VocalNeal said:

But does the RCCD device know which is Line or Neutral?

 

There is no terminal designation on the device.

 

It trips when the test button is pressed.

A two-pole RCD will function properly either way - if no designation, then it doesn't matter.

 

But, L and N should not be assumed based on color.  N should not be connected to single-pole breaker and it should not be switched.  When designated, L, N, and E should always be connected accordingly.

[VocalNeal 7,275]

28 minutes ago, bankruatsteve said:

N should not be connected to single-pole breaker and it should not be switched.

That makes sense. I'll check that the internal relay is double pole.

 

 

 

[Crossy 27,214]

1 hour ago, VocalNeal said:

But does the RCCD device know which is Line or Neutral?

There is no terminal designation on the device.

It trips when the test button is pressed.

 

Can you post a photo of the device in question? If not a manufacturer and part number?

 

[VocalNeal 7,275]

Can do but I am not at home at present. Japanese RCCD. Starts with a K.

 

Was in the house when I viewed but one was broken so I went to local electrical store with sample and they gave me an exact copy. 

 

From memory 30mA

[bankruatsteve 1,805]

10 minutes ago, VocalNeal said:

Can do but I am not at home at present. Japanese RCCD. Starts with a K.

Can't remember seeing the term "RCCD".  Is that what many would call a "RCCB" or "RCBO"?

[VocalNeal 7,275]

10 minutes ago, bankruatsteve said:

Can't remember seeing the term "RCCD".  Is that what many would call a "RCCB" or "RCBO"?

I call them GFI but some use the residual current terminology. 

[sometimewoodworker 3,060]

22 minutes ago, bankruatsteve said:

Can't remember seeing the term "RCCD".  Is that what many would call a "RCCB" or "RCBO"?

RCD, RCCD and RCCB (device vs breaker)  are the same but an RCBO is not.

 

Quote

About RCCB 

RCCB (residual current circuit breaker) detects current difference between neutral and live conductors. The difference is also known as ‘residual current’. Proper functioning circuits will have balanced neutral and live current and the residual current occurs when there is some potential shock hazard or fault. The device is an RCD i.e. residual current device class of item and circuit breaker, which is a part of its name, indicates that the electrical product sits within costumer unit with the other CBs (circuit breakers).

It should not be confused with MCB current rating at which it will trip out.

Defining RCBO

RCBO means residual current circuit breaker with over current protection, which is a combination of RCCB and MCB.

When current leakage occurs, the RCCB (residual current detecting element) will trip the entire circuit. Similarly, in case the circuit is overloaded then components of internal magnetic/thermal circuit breakers are capable to trip the electronic device.

But I don’t know which type a GFI is 

Edited September 30, 2020 by sometimewoodworker

[bankruatsteve 1,805]

3 minutes ago, VocalNeal said:

I call them GFI but some use the residual current terminology. 

A GFI or GFCI normally has no overcurrent protection - same as RCD and RCCB.  RCBO combine RCD with MCB.  Some RCBO are single pole but when used as single phase main breaker are always 2-pole.

[bankruatsteve 1,805]

31 minutes ago, sometimewoodworker said:

RCD, RCCD and RCCB (device vs breaker)  are the same but an RCBO is not.

 

Right.  Well, the "B" in RCCB is for breaker.  Whatever, I just didn't know what "RCCD" is referring to.

[VocalNeal 7,275]

2 hours ago, bankruatsteve said:

Right.  Well, the "B" in RCCB is for breaker.  Whatever, I just didn't know what "RCCD" is referring to.

I think the "D" is for device

[bankruatsteve 1,805]

20 minutes ago, VocalNeal said:

I think the "D" is for device

I suppose it would be if that was a common term used for RCD - but it's not that I am aware.  IE: Google RCCD and you won't get anything resembling a RCD.  At least I don't.  Cheers.