AMENDMENT 2 - 18th EDITION – RCD TESTING CHANGES – SHORTS 6

This is the sixth in our video shorts series and in this video we will look at the changes that affect RCD testing and in particular at type AC and type A devices.

There are significant changes to this part of the testing process and fortunately for us they do actually simplify the process of testing RCDs.

This video is No.136 on our YouTube channel where we have videos on a wide range of electrical topics.

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Always work safely, electricity can be dangerous. If you are unsure, stop and seek advice.
This video is provided for guidance only. Every electrical situation is different, please check and ensure that you are applying this learning information to your own individual circumstances correctly and safely. If in doubt, stop and seek competent advice.

[jmack]

Excellent as usual, halfway through I was thinking I had to buy a new mft, lol. Your tip on setting to 100 at 1/2 saved the day. It's simple when someone educates you

[imranshaki]

Very useful knowledge. never considered this before. Well done Dave, really really appreciate

[luciusgeorge]

i am very thankful for this lesson its difficult to find

[Edgariux]

Great video but how would you code the rcds that are ac type in an eicr. Comercial property ?

[seandempsey]

IET put up a video on the amendment 2 changes, and they say we are now only required to test at 1 times on the Test instruments AC setting irrespective of RCD type and they should trip in less then 300 ms, and the 1/2 times and 5times tests are no longer a requirement
And we are not required to buy new test instruments, but we can continue doing all the tests if we want to . I will continue to do all RCD test as I always have done.
Fantastic video very well explained.

The effectiveness of automatic disconnection of supply by RCD shall be verified using suitable test equipment according to BSEN 61557.6
NOTE: regardless of RCD type effectiveness is deemed to have been verified where an RCD disconnects within the times stated below with an alternating current test at the rated residual aperrating current (I^n) for general non- delay type 300ms maximum
For delay ’s’ type RCD between 130ms minimum and 500ms maximum, oh I am not trying to correct you or be disrespectful
Fantastic video As always Dave 👍👍👍👍❤️

[rowles]

Great video.... Done my 18th edition. But not the ammendment.

[alancooper]

Great clarification thanks Dave. I take it the 1/2 times is now ignored also apart from fault finding purposes?

[oddjob]

Hi Dave...would I still carry out the 5x and 1/2x if the circuit was designed in the 18th edition, but before the amendment. Many thanks in advance 👍

[nicholasmifsud]

Hi Dave, thanks for your very detailed videos and understandable. If I may ask you what type of multifunction tester do you recommend to an electrician, the brand and type for domestic and commercial electrical installations?

[JamesJames-umxq]

Can anyone advise ? I thought the x5 (150mA) test on a TN system was to verify the device's function for additional protection; which is what an RCD is for isnt it? If its no longer a requirement to record x5 results then what are we testing an RCD for ? Have I been thinking wrong all this time and a x1 (30mA) test below 300ms satisfies additional protection ?

[mikep-j]

The advice in the video is incompatible with the latest version of guidance note 3, which is very clear - A type 'A' RCD, or indeed type 'B' or 'F' any new type yet to be invented as well, should be tested as if it was an AC type at the rated current - so test at 30mA with an alternating current fault. The other tests, such as an unsmoothed DC at 42mA are options on many test instruments but are not listed in the minimum set of tests. For a normal alternating current still test at 1* and note the slowest trip time.

[kevinrose]

You cannot do a 100mA x 1/2 test on a 30mA RCD. The tester does a check to make sure the voltage of the earthed metalwork does not go above 50V just before the actual test at 1/2 times the selected current, irrespective of the multiplier selected. It would do a 50mA precheck and trip the RCD with the display saying "trp" and not with a trip time.
I have only come across the problem with AC RCDs failing when someone hasn't realised that the tester is set to type A. When testing type A RCDs on a type AC setting there is no problem.