RCD Trip switch too sensitive

[Spark123]

The trips do come with variable sensitivity and time delays but to protect people it has to be 30mA @ 40ms so that option is not open to you.

30mA RCDs to EN61008/9:
30mA @ <300mS
150mA @ <40mS

OP, do you have any surge protectors plugged in?

 

[ericmark]

The trips do come with variable sensitivity and time delays but to protect people it has to be 30mA @ 40ms so that option is not open to you.

30mA RCDs to EN61008/9:
30mA @ <300mS
150mA @ <40mS

OP, do you have any surge protectors plugged in?

That is likely to confuse the layman. I know that the 30mA RCD must trip at both positive and negative cycles at 30mA and at 5 times 30mA it must trip again both half cycles in 40ms. It must also not trip at half rating i.e. 15mA again both + and -. However the layman is not testing the RCD he will get some one with a meter to test it for him. So likely reading your post he will think he has three options.
30mA RCDs to EN61008/9:
30mA @ <300mS
150mA @ <40mS
This is not correct. He has only two RCD's he can fit a 30mA or 10mA and he will not want to go more sensitive so 30mA is only real option.
To say:-
415.1.1 The use of RCDs with a rated residual operating current (I&#8710;n) not exceeding 30 mA and an operating time not exceeding 40 ms at a residual current of 5 I&#8710;n is recognised in a.c. systems as additional protection in the event of failure of the provision for basic protection and/or the provision for fault protection or carelessness by users.

Is a bit of a mouth full and although not strictly correct 30mA @ 40mS is a easy abbreviation. What I want to point out is pushing the "Test" button on the RCD does not "TEST" the RCD but only checks it is mechanically sound. One does need to measure time and a stop watch will not measure 40mS.

 

[Spark123]

Just say a bog standard 30mA RCD then, no need to bring trip times into it to confuse the laymen.

 

[SwindonSpark]

CornishMaid wrote:

I will try to get a photo up later, but for the meantime, details from the trip unit are:

Crabtree 854293 RCCB 80A 30mA List No: 380/030

If that means anything to anyone.

Note this bit 854293 in her descrription.
This is a BS 4293 RCD not a BS EN 61008 RCD
She has read figure 8 for letter B and figure 5 for letter S

Slight difference only in that 1 X I(delta)n is 200ms not 300ms
Guidance note 3 page 56