RCD reluctant to reset after being isolated

[gogsboy]

I recently removed a mains socket plate from the wall to see if I could get a look at the insulation in the cavity.

Prior to doing this I flicked the RCD on the board.

When I was finished I went to put the breaker back on but it was lazy for want of a better word, it seemed to want to sit in the middle, neither on or off.

It does go eventually but just doesn't feel as precise and positive as the others which always go into place first time.

Is this likely to be a faulty RCD or some problem making it do this, I never touched anything with regards to the actually wiring

Thanks

 

[JohnD]

Are you sure it is an RCD not an MCB?

What make is it?

What letters and numbers are on the front of the breaker that seems odd?

How old is it?

You can post a picture if you like.

//www.diynot.com/forums/viewtopic.php?t=129539

 

[Spark123]

On some RCDs when they trip the handle goes to the middle, in order to reset it you have to switch it fully down before returning it fully up.

 

[gogsboy]

Think its and RCD,

MK is the make and it's quite new, maybe about 1.5 years

Here is a link to photos : //www.diynot.com/network/gogsboy/albums/5133/20533


3 socket ones are next to the cooker one, the one that didn't want to return was the one next to the cooker on the board

 

[Spark123]

Yep, it is an RCD. That brand, as I said above requires you to push the handle fully down before it will reset.

 

[JohnD]

do you mean to the left of the cooker one, or to the right of the cooker one?

 

[Spark123]

I was referring to the one which has RCD written on it btw

 

[JohnD]

ah, but was he?

 

[Spark123]

I've not known an MCB to trip to half way, only some RCDs and RCBOs.

 

[gogsboy]

do you mean to the left of the cooker one, or to the right of the cooker one?

To the right which I now understand just to be MCB's protected by an RCD?

 

[gogsboy]

I've not known an MCB to trip to half way, only some RCDs and RCBOs.

Is there usually a particular reason for this?

 

[JohnD]

Aha!

that ought to just click up and down. Maybe yours is faulty. Compare it to the others by switching them up and down. Unless you have some electrical ability and skill, fitting a replacement is a job for an electrician, but it is not a difficult or complex one. however some terminals and connections in a CU remain live and dangerous even after you have switched it off, hence the need for knowledge and experience.

you say it is only a year or two old so the part should be easy to get and your electrician will probably have one in the van. Make sure he fits an MK part with the same part no, others might nearly fit but are not correct.

 

[Spark123]

I've not known an MCB to trip to half way, only some RCDs and RCBOs.

Is there usually a particular reason for this?

They are purposely designed that way so you have to go through a positive sequence to reset them.

 

[gogsboy]

So what is the secret to the sequence, I have tried all the others, they seem to fall into place no bother

 

[Spark123]

If it is an MCB then I'd replace it with a new one.

When you press the test button on the RCD (the big one to the left of the cooker MCB) it should trip and the handle will stop half way. To reset it you need to press the handle all the way down before pressing it up.