RCBOs fails 5I test

[BlueToBits]

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)

 

[telectrix]

several times on RCDs. even took my mft for checking. apparently some wylex units are suspect. they have recalled MCBs recently

 

[BlueToBits]

Thanks
I have recently tested about 100 of these and I found 11 with rated trip times of around 20ms but 5I trip times of over 50ms. My tester is probably due for re-calibration but I find it surprising they pass at 30mA but fail at 150mA where others of the same type, rating and manufacturer are OK.

 

[Tosh]

thanks
i have recently tested about 100 of these and i found 11 with rated trip times of around 20ms but 5i trip times of over 50ms. My tester is probably due for re-calibration but i find it surprising they pass at 30ma but fail at 150ma where others of the same type, rating and manufacturer are ok.

in the select certs that i use it only asks for x5 test times on 30ma r.c.d,s not r.c.b.o,s. So i only test them on x1

 

[J@mes]

Cant say I have, I test about 150 RCD's of all different types, makes and sizes every 6 months and they seem to either pass on all tests or fail on all tests.

tester calibrated annually too.

 

[Risteard]

in the select certs that i use it only asks for x5 test times on 30ma r.c.d,s not r.c.b.o,s. So i only test them on x1

RCBOs are RCDs.

 

[Mark_Burgess]

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)

Any particular brand that fail?

 

[BlueToBits]

All but one were in the same installation and were Crabtree Loadstars in TP distribution boards, the other I found yesterday (whilst on my annual NICEIC assessment) was a Denman's "Basic"

I found that taking an rcbo out of the board and shaking it around hitting it almost to the point of causing physical damage would sometimes give a satisfactory test but not consistently. I did suggest to the NICEIC that I could change the wording on the quaterly test label...

 

[Guest123]

in the select certs that i use it only asks for x5 test times on 30ma r.c.d,s not r.c.b.o,s. So i only test them on x1

Really???

So when a 32A 30mA RCBO is used to give additional earth fault protection to a socket outlet circuit for instance, you would not test a 5x because it isn't an RCD???

 

[Risteard]

Really???

So when a 32A 30mA RCBO is used to give additional earth fault protection to a socket outlet circuit for instance, you would not test a 5x because it isn't an RCD???

Even though it is actually an RCD!!!

 

[nickblake]

ive always found square D on x 1 always close to or over the 40ms mark ,other makes crabtree wylex hagar prolec niglon to name a few test below 30ma

 

[Guest123]

Even though it is actually an RCD!!!

That was the thought I was trying to evoke.

Essentially the earth fault elements of RCD and RCBO are the same.

 

[Mark_Burgess]

I found that taking an rcbo out of the board and shaking it around hitting it almost to the point of causing physical damage would sometimes give a satisfactory test but not consistently..

You need a technical adjustment tool

But on a serious note, I have not come across any failures lately, mainly Hager, Wylex and a load of Zehler I have fitted from Meteor Electrical, all I have fitted recently had exactly the same results and I started to wonder if my tester was playing up, tried with another tester and all the same.

 

[Sparky Ninja]

in the select certs that i use it only asks for x5 test times on 30ma r.c.d,s not r.c.b.o,s. So i only test them on x1

Can I ask you please if you are serious about your statement? Or if it is a wind up?

I'm not attempting to humiliate anybody. I'm trying to gain an understanding on the what areas are commonly misunderstood, what with all these express train training companies and courses.

 

[Jimmy Boy]

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