RCBOs fails 5I test

[Risteard]

RCD/RCBO's fitted for additional protection must be tested a x5 with max disconnect @ 40ms as Lenny says BRB 415.1.1

This is perhaps where the confusion arises. Talk of RCDs and RCBOs does not make sense because RCBOs are a type of RCD. RCCBs are also a type of RCD (and therefore to redesignate them "RCD" alone gives rise to confusion).

RCD is a generic term. It does not relate only to one particular type.

 

[Jimmy Boy]

I'm not confused, RCD is a generic term for all devices that operate under fault conditions whether it's a general purpose or RCBO to 61009 if it's for additional protection it's x5 and < 40ms, although oddly the OSG gives 61008's and 61009's as x1 < 300ms where other types are shown as x1 <200ms, now that I do find odd ?

 

[Risteard]

I wasn't saying that you were confused. What I was suggesting was that the misuse of the term RCD may well sow the seeds of confusion in other people. And yes, it is true that the older BS models were within 200mS and newer BS EN models are within 300mS. That is not a mistake.

 

[BlueToBits]

Bring back the current operated ELCB.

 

[rocker]

Does the fault occur at 0 and 180 degrees?

 

[trebor]

Hi
Has anyone else found that about 10% of RCBOs appear to fail the 5I test but pass at the rated (30mA) current?

(Telaris 0100 plus)

I did an RCD test on a circuit recently which passed ok on the 1 times but failed miserably on the 5 times, in the end it turned out that there was a plug in powerbreaker in a socket hidden from view, once removed the RCD tested out perfectly, now i`m thinking as RCBO`s are commoned up on a board could this be part of the problem, may be worth trying it with any multiple RCBO`s switched off, just a thought

 

[jamie-spark]

i have recently installed a Hager rcbo's supplying lights. It passed on the 30ma test then failed the 150ma test it was well over the 40ms. So i got another one tested it failed again then i tried it with the load disconnected and hey presto it worked. Now if i phone up and tell them this, they may tell me that its ok. But it cant offer additional protection as it supplies lights in a shower room.

Any one else had found this

 

[nickblake]

Did you test it correctly meter set to 30 ma for 30ma RCBO , then x1 then x5 then Ramp test

 

[tony mc]

I would have another look at the circuit and do another set of tests as something does not add up.

Agree with nickblake re check and ramp test.!!!

 

[jamie-spark]

meter is set up correctly ,recently calabrated and i checked it on a check box, circuit is wire correct ie tested , also installed 16amp 30ma hager rcbo supplying a hand dryer circuit and this one passes (although there is no load on this as the dryers are not running when i test) i have heard a lot of people have had these problems.i will phone the technical dept monday i think

 

[SPARTYKUS]

Best times I have ever seen are for the good old lumbering great Wylex RCDs that were used as an up front double pole main switch, you know the type in their own enlosure with a box about the size of a box of tissues. low 5 ms's very fast.

 

[jamie-spark]

just thought i would update this since i spoke to hager technical dept ant the IET.Also so the ESC switched on issue 18

Hi Jamie

Please see the reply from Hager technical manager I received earlier. I recall a megger engineer on the national committee mentioned something similar about the meters being affected by this when loads were in circuit

Hi Richard,

Quick reply as I am in and out of company meetings!!

I hope the following answers the questions. Out of interest, please can you tell me the type of connected load.

I am assuming thatyour comment "it fails to trip at 150ma (x5) within 40 mS" means ittrips, but appears to exceed the maximum time?

This is a known phenomenon attributed to the load (capacitance) influencing the RCD tester.

This is why the correct RCD test procedure prescribed in GNs states:"The load supplied should be disconnected during the test".

The ESC are currently investigating this, please see attached, page 15 "Influence of connected loads".



Richard Townsend
Senior Engineer
Standards and Compliance
The IET