New 18th Edition.

[Jay Sparks]

Hi Guys & Gals,

This is my first new post in quite a while.

I was in a meeting today with some interesting and influential people in the industry and one of the things on the agenda was the 18th Edition. At the moment it is scheduled to be published in July 2018, although this date will possibly change.

Some of the proposed changes are:

Adding an new section to all the certs for RCD ramp testing
Removing the need for the 1/2 x In test ( which makes some sense considering the above)
Re-introduction of VOELCB's, mainly for car charging points
Functional earthing on inverters for PV installs

Now these are just a few that they mentioned and they are not set in stone but I like the sound of the 1st one. There's not many people that even know what this test is and when you would perform it.

Your thoughts on these proposed changes?

Jay

 

[Deleted member 26818]

Yeah 2018 sounds likely.
Not sure about the ramp testing, sounds pointless, unless they intend raising the minimum tripping current allowed.
Yes, reintroduction of VOELCBs is an option to get around the 3 monthly test button operation.
Is functional earthing necessary for PV inverters?

 

[7029 dave]

Steady don't wish your life away.

 

[Octopus]

Hardly worthy of a new set of books nor another exam.

a free electronic download would be more appropriate.


my crystal ball sees more sparks moving to the dark dudedude

 

[NDG Elecs]

Domestic ramp testing surely only requires another box rather than a section - unless I am missing something. I routinely ramp test all RCDs and record the results, so a dedicated box to record this ain't a bad idea.

Maybe they should do away with a load of the inane tick boxes such as 'connections being sound and under no undue mechanical strain'. The schedule of inspections is much more useful for an EICR than an EIC. And I won't comment on the condition of the service cable, it is outside the remit of 7671 and up to the DNOs to check their own gear (which we can't touch) in my view. I would report anything obviously dangerous but do not see why we should be doing their work. Coupled with smart meters they will have nowt left to do!

 

[davesparks]

The schedule of inspections is an important part of initial verification as it provides a means of recording that the inspections have been carried out.

 

[davesparks]

Domestic ramp testing surely only requires another box rather than a section - unless I am missing something. I routinely ramp test all RCDs and record the results, so a dedicated box to record this ain't a bad idea.

What would ramp testing achieve that the existing RCD test procedure doesn't?
The test is designed in line with the standard to which an RCD is built and the acceptable pass values are set by that.

What trip current would you be looking for? The regs only call for a current not exceeding 30mA so a tripping time test carried out at 30mA is adequate to sure it meets that.

There was rumour of a requirement for the <50V touch voltage to tested as part of the RCD test being added in the years leading up to the 17th coming out. Thankfully it came to nothing

 

[NDG Elecs]

The schedule of inspections is an important part of initial verification as it provides a means of recording that the inspections have been carried out.

The point I am making is items like 5.6 on the model forms; the CCC of a cable and its PD are recorded on the schedule of test results. When looking at previous records I always go to that sheet as that will tell me far more than 2/3 pages of tick boxes.

I am not saying do away with all the inspections. But some are fairly pointless in my view.

 

[Deleted member 26818]

The half X In shows if the RCD is too sensitive.
As for the tick boxes, they're useful as a reminder of what needs testing.

 

[andyb]

And I won't comment on the condition of the service cable, it is outside the remit of 7671 and up to the DNOs to check their own gear (which we can't touch) in my view. I would report anything obviously dangerous but do not see why we should be doing their work.

I think you're missing the point here TGO. As you said you would report anything dangerous you are already inspecting the service head and cable, the tick box is for you to record this fact. It's to cover you more than anything else.
If there's problems later on with the service head for example, you've got documented evidence that you inspected it when you did your work and that it was fine.

 

[NDG Elecs]

What would ramp testing achieve that the existing RCD test procedure doesn't?
The test is designed in line with the standard to which an RCD is built and the acceptable pass values are set by that.

What trip current would you be looking for? The regs only call for a current not exceeding 30mA so a tripping time test carried out at 30mA is adequate to sure it meets that.

There was rumour of a requirement for the <50V touch voltage to tested as part of the RCD test being added in the years leading up to the 17th coming out. Thankfully it came to nothing

It's useful for fault finding purposes in relation to cumulative earth leakage. I don't know the workings of RCDs inside out. But I presume that over time the mA threshold can change, which is not a bad thing to have documented. I understand what you are saying, but given that it takes no time to carry out I prefer to record it.

I find it a bit odd that we don't test MCBs functionality.

 

[NDG Elecs]

I think you're missing the point here TGO. As you said you would report anything dangerous you are already inspecting the service head and cable, the tick box is for you to record this fact. It's to cover you more than anything else.
If there's problems later on with the service head for example, you've got documented evidence that you inspected it when you did your work and that it was fine.

Not my job to do it though. I am not 'competent' to pull a DNO fuse - even if it's brand new and not likely to break apart - so why should I do their job for them. As I said, it's not in the remit of 7671.

I do understand what you are saying about arse covering. That's what a lot of the tick boxes are though.

 

[NDG Elecs]

The half X In shows if the RCD is too sensitive.
As for the tick boxes, they're useful as a reminder of what needs testing.

Yep, fair point re acting as a reminder. For an EICR I would keep pretty much all the tick boxes. But do away with some on an EIC.

My gripe has absolutely NOTHING to do with the fact I have approx four certs I need to type up this weekend!! Haha!

 

[andyb]

Not my job to do it though. I am not 'competent' to pull a DNO fuse - even if it's brand new and not likely to break apart - so why should I do their job for them. As I said, it's not in the remit of 7671.

I do understand what you are saying about arse covering. That's what a lot of the tick boxes are though.

But it is your job and it is in the remit of 7671. Right at the start of the regs under additions and alterations it says that before you start you must ascertain that the existing equipment including that of the distributor must be adequate for whatever you are doing.
The tick box is for you to confirm that you have done this.

 

[NDG Elecs]

But it is your job and it is in the remit of 7671. Right at the start of the regs under additions and alterations it says that before you start you must ascertain that the existing equipment including that of the distributor must be adequate for whatever you are doing.
The tick box is for you to confirm that you have done this.

I agree partly with what you are saying Andy! But why should I check what the condition of the meter is like!? A quick glance over to see if it looks 100% safe, but that's about it. Maybe the meter readers should be checking this. I think it's partly to do with the smart meter rollout and passing the buck myself.

If the DNOs tails need upgrading I ring them. The main earth is checked also. I don't tick a box to say that their service cable is OK though. That's N/V for me.

 

[davesparks]

It's useful for fault finding purposes in relation to cumulative earth leakage. I don't know the workings of RCDs inside out. But I presume that over time the mA threshold can change, which is not a bad thing to have documented. I understand what you are saying, but given that it takes no time to carry out I prefer to record it.

I find it a bit odd that we don't test MCBs functionality.

Fault finding yes, but that is a bit different to recording it on a test sheet.
The trip threshold won't change, it's set at the factory and that's it. I'd only want to see it recorded for variable RCDs where by their very nature it can change.

Carry out the unnecessary test by all means, but don't force the rest of us in to having to do it and write the result down.

 

[andyb]

I agree partly with what you are saying Andy! But why should I check what the condition of the meter is like!? A quick glance over to see if it looks 100% safe, but that's about it. Maybe the meter readers should be checking this. I think it's partly to do with the smart meter rollout and passing the buck myself.

If the DNOs tails need upgrading I ring them. The main earth is checked also. I don't tick a box to say that their service cable is OK though. That's N/V for me.

Ok then TGO, let's agree to partly disagree.
Though I think you're wriggling a bit now. It seems you are doing about as much as we all do, ie a quick look over. You just don't like to tick the box.

 

[NDG Elecs]

Fault finding yes, but that is a bit different to recording it on a test sheet.
The trip threshold won't change, it's set at the factory and that's it. I'd only want to see it recorded for variable RCDs where by their very nature it can change.

Carry out the unnecessary test by all means, but don't force the rest of us in to having to do it and write the result down.

Didn't realise the threshold was unchanging over time. I assumed it may well alter by a couple of mA's. I find a lot of RCDs, when ramped, can trip on the low side <23mA. I would expect the factory setting to be say 4mA higher. 90% (27mA) seems a good threshold to me!

It isn't me potentially forcing you Dave, it be the brains of the IET in 2018 possibly! So are you happy to tick/nv/lim/na all the boxes on the inspections. I do read them each and every time and fill in accordingly, but a good few are daft.

 

[NDG Elecs]

Ok then TGO, let's agree to partly disagree.
Though I think you're wriggling a bit now. It seems you are doing about as much as we all do, ie a quick look over. You just don't like to tick the box.

Feeling rebellious after three beers tonight, that's what it is!

 

[davesparks]

Didn't realise the threshold was unchanging over time. I assumed it may well alter by a couple of mA's. I find a lot of RCDs, when ramped, can trip on the low side <23mA. I would expect the factory setting to be say 4mA higher. 90% (27mA) seems a good threshold to me!

It isn't me potentially forcing you Dave, it be the brains of the IET in 2018 possibly! So are you happy to tick/nv/lim/na all the boxes on the inspections. I do read them each and every time and fill in accordingly, but a good few are daft.

Why do you think 23mA is low? Afaik the standard requires them to trip >15 mAand <30 mA.

One problem that will arise is people who don't know better replacing RCDs because they are 'faulty' when they don't trip dead on 30mA.

 

[Risteard]

Why do you think 23mA is low? Afaik the standard requires them to trip >15 mAand <30 mA.

Indeed it does, which is why I never bother with ramp tests - a waste of time except perhaps for trying to establish the leakage on an appliance etc.

But half I delta n and I delta n will prove that the RCD is functioning correctly.

 

[NDG Elecs]

Why do you think 23mA is low? Afaik the standard requires them to trip >15 mAand <30 mA.

One problem that will arise is people who don't know better replacing RCDs because they are 'faulty' when they don't trip dead on 30mA.

Not au fait with the standard Dave, and didn't know it was between 15-30mA. Learn something new every day and all that. I have never replaced a RCD unless the trip times were incorrect, and I wouldn't do so if it ramped on the low side. If an RCD is tripping then obviously better to find and remedy the root causes. I am just surprised that the majority of RCDs I have tested are generally around 23mA. Guess the manufacturers are going for the middle ground.

 

[davesparks]

Not au fait with the standard Dave, and didn't know it was between 15-30mA. Learn something new every day and all that. I have never replaced a RCD unless the trip times were incorrect, and I wouldn't do so if it ramped on the low side. If an RCD is tripping then obviously better to find and remedy the root causes. I am just surprised that the majority of RCDs I have tested are generally around 23mA. Guess the manufacturers are going for the middle ground.

It is, and that is what the 1/2x and 1x test is all about!
There is also a requirement that the touch voltage be limited to 50V, which I guess may have some bearing on the actual trip setting (pure guess on my part)

 

[colshaws]

Had my Elecsa assessment today and asked about proposed changes in the 18th and one that was mentioned was the possibility of a requirement for C.U 's to be all RCBO as standard to avoid nuisence tripping.

 

[Darkwood]

I think we are all forgetting what is for me the most important question relative to the new 18th edition and it is 'What colour will the cover be?'