How to tell if a circuit is on an RCD?

[crt]

I'm trying to work out which of our household circuits are protected by an RCD. In other installations we've had it was quite clear that individual circuits were protected and could be tripped and then reset individually. In our new place, however, it looks like the whole of one bank of circuits on a consumer unit are protected - there is a single yellow test switch at one end of the bank. We then have another set of circuits on a separate consumer unit which doesn't have the yellow test circuit (but this one has the main switch).

What should I be looking for??

If all the circuits are RCD protected would this mean there is no need for supplementary bonding in the bathrooms? ... and if so perhaps this would explain why there isn't any on the plumbing that was done quite recently.

Thanks.

 

[Spark123]

Press the test button and see which circuits it knocks off! Read the labels on the CU to see what it feeds?
RCD protection of all circuits entering the bathroom is only one of the criteria for ommision of supplementary bonding, you'd need to ensure the rest of the regs are met.

 

[RF Lighting]

Press the test button and see what goes off.

It is unlikely that your bathroom lights will be RCD protected, so supplementary bonding should be installed in your bathroom.

 

[Steve]

Push the test switch, see what happens.

Show us a photo of it and we'll tell you for sure.

 

[RF Lighting]

1-0 to spark123

 

[sparkybird]

Hi

To do it safely (ie Without taking the cover off the fuseboard), I would trip the RCD (Yellow button), then go around your house checking what is off ie lights, sockets (use a radio or lamp).

Generally if all circuits in the bathroom (lights, shaver, towel rail?) are on RCD then no supp bonding required as long as main bonding to gas and water in place. The supp bonding is sometimes done at the boiler if it;s not too far from the bathroom, so might be worth checking there

SB

Edit I'm far too slow at typing! There were NO replies to this post when I started!

 

[crt]

Wow, that was quick. Thanks. I will try the tests suggested.

The circuits, unhelpfully, are not accurately marked on the CU. If the bathroom lights are not on the RCD, and they are the only electrical installation in the bathroom, could this account for the absence of bonding?

Everything else appears to be have been done to a high standard on both the plumbing and electrical side so I am assuming there is a good reason for no bonding.

I will try to post some pictures when I can get my pc to speak to my camera.

 

[Spark123]

Is the pipework plastic or metal?

 

[crt]

Pipework is all metal.

 

[Spark123]

Supplementary bonding is required between each extraneous conductive part i.e. each pipe and any exposed conductive parts within the zones, i.e. possibly the lighting circuit.

 

[sparkiedave]

to test to see if all the pipework is linked within the bathroom, get hold of a multimeter and test for continuity between things like the radiator and the taps, if you get a very low reading (ideally below 0.05 ohms) then the bonding between these is uneccesary, but it would still need to be connected to any non rcd protected items on the bathroom, usually the lights, or you could get an RCD or RCBO fitted to the lighting circuit which may be easier & cheaper.

 

[Taylortwocities]

Where have you checked for the supp bonding? Have you checked in the airing cupboard, its not unusual for the bonding to be done there.

 

[ban-all-sheds]

Or in the loft if it's tank fed.

 

[crt]

here are some photos of what I've got.

This is the CU with what I think are the RCD circuits:

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And this is the other one with the main switch (and no yellow test switch):

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To respond to the most recent suggestions - there is no bonding in the airing cupboard (it is quite a distance from the bathroom anyway), and none in the loft (and it's a pressurised system).

CRT[/img]

 

[ban-all-sheds]

here are some photos of what I've got.

This is the CU with what I think are the RCD circuits:

They are.

And this is the other one with the main switch (and no yellow test switch):

They aren't.

To respond to the most recent suggestions - there is no bonding in the airing cupboard (it is quite a distance from the bathroom anyway), and none in the loft (and it's a pressurised system).

Take a look at the diagrams here: //www.diynot.com/wiki/electrics:bathroom-zones and tell us where the light and the switch are....