Type A RCD's and testing

[mattg4321]

Following on from a recent topic on here I thought I'd start a poll on this. Various videos on youtube are suggesting we should be thinking about phasing out Type AC RCD's and use Type A instead

See Sparky Ninja here

Also of interest is GSH Electrical's video

which deals with problems testing Hager's Type A RCD's and Hager's guidance on how to work around the problem.

I noticed on this video that the Megger 1700 series tester they were using has a specific test mode for Type A RCD's. As far as I can see, my Megger 1553 doesn't have this capability. I can find no guidance on whether it is acceptable to continue testing Type A RCD's with the Megger 1500 series on 'AC' setting.

Any thoughts?

 

[telectrix]

i've got a 1553 and would like to know as well.

 

[cliffed]

It’s all got a bit confusing.

 

[APE37]

Hi guys,
I may be wrong and maybe one of the other guys on here with more experience will correct me, the megger 1700 series have the facility to test type a rcd in an all in one test. I have a 1552 and thinking with the older model it has a facility to switch between ac and DC, so maybe that you will need to test the rcd on ac, then switch and test to DC and then take the worst case readings to enter on the certificate. This is the way I see it, I may be wrong and open to be putting right by others. As a side note I was reading up on the hager website about rcd types and if you intend to instsll PV or electric vehicle chargers you may need a type B rcd, which 1500s I believe don't have the facility? Also it did state that the use of type F rcd may be needed for circuits like kitchens and utility rooms due to the nature of modern appliances. Don't know if that is true but what I read on the hager website.

 

[Risteard]

Following on from a recent topic on here I thought I'd start a poll on this. Various videos on youtube are suggesting we should be thinking about phasing out Type AC RCD's and use Type A instead

See Sparky Ninja here

Also of interest is GSH Electrical's video

which deals with problems testing Hager's Type A RCD's and Hager's guidance on how to work around the problem.

I noticed on this video that the Megger 1700 series tester they were using has a specific test mode for Type A RCD's. As far as I can see, my Megger 1553 doesn't have this capability. I can find no guidance on whether it is acceptable to continue testing Type A RCD's with the Megger 1500 series on 'AC' setting.

Any thoughts?

In my opinion Type AC RCDs have not been the correct device in many situations for a long time now. This isn't actually new to the 18th Edition - the Regulations raised this issue before, but perhaps less forcefully.

In fact outside of the UK you would be hard pushed to find Type AC RCDs - much of the world phased them out long ago.

 

[richy3333]

Would it not be quicker for people to stop knocking Hager and ring up Megger about their 15XX series tester? I really don't see the issue with Hager and using a Megger MFT to test type A RCD's. Are some people too lazy or not capable of tuning a few dials and pressing a couple of buttons. Lighten up people lets get back to slagging off the NICEIC!

 

[mattg4321]

Hi guys,
I may be wrong and maybe one of the other guys on here with more experience will correct me, the megger 1700 series have the facility to test type a rcd in an all in one test. I have a 1552 and thinking with the older model it has a facility to switch between ac and DC, so maybe that you will need to test the rcd on ac, then switch and test to DC and then take the worst case readings to enter on the certificate. This is the way I see it, I may be wrong and open to be putting right by others. As a side note I was reading up on the hager website about rcd types and if you intend to instsll PV or electric vehicle chargers you may need a type B rcd, which 1500s I believe don't have the facility? Also it did state that the use of type F rcd may be needed for circuits like kitchens and utility rooms due to the nature of modern appliances. Don't know if that is true but what I read on the hager website.

I was looking through the instructions for the Megger 1500 series earlier and it doesn't give too much information on the AC/DC tests.

 

[APE37]

Unfortunately Richy I have contacted megger, that was 3 weeks ago and still no reply. Agree with moaning about the NICEIC though.

 

[HappyHippyDad]

Following on from a recent topic on here I thought I'd start a poll on this. Various videos on youtube are suggesting we should be thinking about phasing out Type AC RCD's and use Type A instead

See Sparky Ninja here

Also of interest is GSH Electrical's video

which deals with problems testing Hager's Type A RCD's and Hager's guidance on how to work around the problem.

I noticed on this video that the Megger 1700 series tester they were using has a specific test mode for Type A RCD's. As far as I can see, my Megger 1553 doesn't have this capability. I can find no guidance on whether it is acceptable to continue testing Type A RCD's with the Megger 1500 series on 'AC' setting.

Any thoughts?

An interesting thread Matt but could I ask where your ideas are coming from? Is it from the IET or Hagar or just some video clips from youtube? The new section in BS7671 531.3.3 actually says 'for general purposes, Type AC RCD's may be used', I can't see it suggesting Type A RCD's, it merely informs us of the characteristics of a Type A RCD and says 'the appropriate RCD shall be selected'. Hence, this would be a Type AC RCD as suggested by BS7671.

However, from the Electrium website it says the term RCD is used over 250 times in BS7671 so I may be missing something!

 

[AJshep]

Depends..
AC RCDs can still be used, depends on the installation, I tend to use A type RCDs for general use now.
Ive tested a few Hager type A RCDs I never get readings this high but I dont have a Megger, I have a Di-log 9118.
I have noticed if I test a 30mA type A RCD using the AC setting on my test kit it will more than likely fail to trip when tested at 150mA ( works fine on the correct srtting though), However, if I test a A type RCD using a Megger 1500 (with no option to select Pulsating DC) it will operate and test as normal.
Wonder how our test kits carry out the A type test ?

 

[Charlie_]

Some testers have pulsing d.c. whilst others have smooth

 

[Andy78]

I'm having to take my old Metrel to a job next week for a mate to be able to test a TPN board full of type A rcbos he installed. He wasn't aware his even older Metrel would not test them.