rcbo testing

[paddyscouse]

hi can some one clarify how to rcd test a rcbo on a lighting circuit, do i test at a light and do i conect to l+n+e or is it better to test at c u. if so do i connect crock to earth bar or earth flex on rcbo then put probes on nuteral on rcbo and outgoing live ?

 

[Octopus]

Depends on the make of the RCBO

 

[Deleted member 9648]

You can test at a light or at the load terminals of the RCBO. Connect L-N-E probes to L-N-E !! at whatever terminals youi are testing at. Testing at a light can give extended trip times due to loads in circuit,so it is often better to test the RCBO at the load terminals with outgoing circuit disconnected.

Some RCBO's have an issue where they wont respond to a test directly connected to the load terminals....in that case connect short tails and test on them.

 

[Geordie Spark]

hi can some one clarify how to rcd test a rcbo on a lighting circuit, do i test at a light and do i conect to l+n+e or is it better to test at c u. if so do i connect crock to earth bar or earth flex on rcbo then put probes on nuteral on rcbo and outgoing live ?

I think if the job is to test the RCBO, then that's what you test.

 

[paddyscouse]

You can test at a light or at the load terminals of the RCBO. Connect L-N-E probes to L-N-E !! at whatever terminals youi are testing at. Testing at a light can give extended trip times due to loads in circuit,so it is often better to test the RCBO at the load terminals with outgoing circuit disconnected.

Some RCBO's have an issue where they wont respond to a test directly connected to the load terminals....in that case connect short tails and test on them.

ok thanks for the help so just to confirm conect to earth wire on rcbo and put tails in live an nuteral just incase there is a issue with direct contact

 

[paddyscouse]

ok thanks for that so just to confirm i can connect to earth wire on rcbo and put tails in l+n load side to resolve any rcbo issues with direct contact

 

[Midwest]

Was going to ask a similar question. Done my 2392, read myOSG & GSN 3 and watched a vid from the ‘learning lounge’ on the same subject.

I’m kind of confused about breaching EWR on live testing. Onan earth loop test on final radial circuits (i.e. lighting), it’s recommended to carry out the calculation method for Zs (=Ze+(R1+R2)), so as not to breach EWR.
However, to do a RCD test on a RCBO radial (i.e. live test),you could only do that at a lighting point, exposing live parts or at the CU (only testing the device), but again with the cover removed and live parts exposed?

As regards IR testing of a RCBO, I see some manufactures state their RCBO can withstand IR testing, but can give false readings, so should be disconnected? I've seen other instructions to disconnect the ‘earthfly lead’ and test each circuit (with RCBO turned off) independently.

Being picky I know, but having my assessment soon, so I want to do it correctly.

Apologies paddyscouse for hyjacking your thread, but think it is asking the same question.

 

[Rich306]

I always turn the RCBO off when conducting an Insulation resistance test.

 

[Deleted member 9648]

Was going to ask a similar question. Done my 2392, read myOSG & GSN 3 and watched a vid from the ‘learning lounge’ on the same subject.

I’m kind of confused about breaching EWR on live testing. Onan earth loop test on final radial circuits (i.e. lighting), it’s recommended to carry out the calculation method for Zs (=Ze+(R1+R2)), so as not to breach EWR.
However, to do a RCD test on a RCBO radial (i.e. live test),you could only do that at a lighting point, exposing live parts or at the CU (only testing the device), but again with the cover removed and live parts exposed?

As regards IR testing of a RCBO, I see some manufactures state their RCBO can withstand IR testing, but can give false readings, so should be disconnected? I've seen other instructions to disconnect the ‘earthfly lead’ and test each circuit (with RCBO turned off) independently.

Being picky I know, but having my assessment soon, so I want to do it correctly.

Apologies paddyscouse for hyjacking your thread, but think it is asking the same question.

Disconnect circuit from RCBO for an IR test.
Live testing is an essential part of testing.Provided you are using correct meters and leads designed for live testing and follow obvious safety proceedures .....crack on.

 

[paddyscouse]

hi guys i need to ask this, im due an eic assesment soon on a c u (rcbo board) and i need to be sure about rcd testing on all circuits (not sockets) so if im to do a rcd test at board do i connect to the nuteral flex on rcbo or to the terminal or do i put a tail in ,do connect to earth flex on rcbo or terminal bar, do i connect to live terminal or put a tail in, reason i mention tails is some one told me you may get no trip issues with direct contact to terminals can some one explain in laymans terms in detail on the best wat to do this test .....apreciated

 

[Midwest]

paddyscouse, just googled rcd testing of rcbo and found another thread, is that you?
http://www.electriciansforums.net/e...-electrical-forum/73726-testing-rcbo-rcd.html

 

[Geoffsd]

RCBO testing is the same as RCCB testing - but upside down.

 

[Pete999]

hi can some one clarify how to rcd test a rcbo on a lighting circuit, do i test at a light and do i conect to l+n+e or is it better to test at c u. if so do i connect crock to earth bar or earth flex on rcbo then put probes on nuteral on rcbo and outgoing live ?

What sort of test equipment have you got, My advice if you have one of the latest 17th testers would be to temp conect a 13a SSO to a suitable point of the lighting circuit and do the test as you would on a SSO circuit Simples

 

[paddyscouse]

kewtch 65 all leads

 

[Midwest]

What sort of test equipment have you got, My advice if you have one of the latest 17th testers would be to temp conect a 13a SSO to a suitable point of the lighting circuit and do the test as you would on a SSO circuit Simples

Funny.

 

[Engineer54]

What sort of test equipment have you got, My advice if you have one of the latest 17th testers would be to temp conect a 13a SSO to a suitable point of the lighting circuit and do the test as you would on a SSO circuit Simples

Strange that, seeing as virtually all the manufactures all state testing at the RCD units terminals!! Nothing wrong with testing down stream, but not for any official/recorded testing!! As has been already stated your testing the RCD unit, not the circuit it's connected as well!!

Are you sure your not getting confused with ELI testing.... lol!!

 

[IQ Electrical]

Strange that, seeing as virtually all the manufactures all state testing at the RCD units terminals!! Nothing wrong with testing down stream, but not for any official/recorded testing!! As has been already stated your testing the RCD unit, not the circuit it's connected as well!!

Are you sure your not getting confused with ELI testing.... lol!!

Exactly-the reason for testing at the terminals of the device is that any capacitance in the circuit (ballasts etc.) while not affecting the actual disconnection time, affect the displayed disconnection time on the test instrument.