2391 Inspection and testing - RCD Test

[gman67]

Hi,

I am doing my 2391 Inspection and testing training course at the mo and I am a bit confused whether we should test RDCs over 30mA at 5x the scale as we do with RCDs 30mA. My trainer says so but my book says that RCDs over 30mA have to be tested at 1x the scale only. The book is called "Practical guide to inspection and testing" by Teddy Ritcher and was released in 2009 so I am sure whether my trainer or the book is right!

Please if someone out there has got sound knowledge about CURRENT RCD testing procedures, could you possibly shed some light for me?

Thanks a lot

 

[tuckermot]

HI GM67

When i test rcd,s i only test x5 on 30ma as it is for personel protection !!!

Richard

 

[SirKit Breaker]

You test 30mA RCD's at x0.5, x1, and x5, at 0 degrees and 180 degrees, and finally test the mechanical trip button. 7 tests in all. On RCD's rated above 30mA, you do not test at x5 rated trip current. This is all covered in GN3.

Cheers........Howard

 

[tuckermot]

agree with sirkit well explained bud

Richard

 

[gman67]

Thanks to you both, you've just confirmed what I thought. I've actually ordered the GN3 yesterday and it should be delivered soon and will be very helpful as the trainer has contradicted the GN3 a few times now and this confuses me so much! Oh well, I think I'll have to count on my instinct and my bibles BS7671, GN3 and on-site guide.

Thanks guys, I appreciate this

 

[Deleted member 26818]

I doubt very much that your tester will be able to test at 5x on higer rated RCDs.
I also doubt very much that anyone would consider it safe to send 500mA, 1500mA or 2500mA down the earth conductors under standard test conditions.

 

[gman67]

Thanks guys for the info, it's all clear now. We've discussed about this today in course and my trainer still think we should test at 500% RCDs over 30mA.

I definately go with your opinion though as I have read this in Part P too!

Thanks again

 

[ian.settle1]

Sounds like your tutor is a bit of a numpty telling the wrong things.

 

[topquark]

Ask him how long it would take to kill someone with 500mA then ask why bother with the testing then! That's the reason for not testing coz you'd already be dead!

 

[Risteard]

The 5I delta n test is for ADDITIONAL protection. Therefore it doesn't apply to RCDs with a rated residual operating current above 30mA (although it applies below 30mA).

300mA and 500mA RCDs are for fire prevention and not to reduce the risk of electric shock.