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Will this old consumer unit pose any issues with an upcoming EICR?

Discuss Will this old consumer unit pose any issues with an upcoming EICR? in the UK Electrical Forum area at ElectriciansForums.net

Neptune

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I've had invaluable advice from this forum in relation to EICR's and clarifying my understanding that just because the consumer unit is "old", it does not need to be replaced. Since then, I had the EICR carried out at my rental property. This went to plan.

I am now scheduling my next EICR on a separate property and this has an even older Consumer Unit but everything works and seems safe e.g. no cracked fittings or exposed cables from my pre-inspection checks.

My question: will this type of Consumer Unit be okay to produce a satisfactory EICR?

Thanks in advance.
 

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I think we have wandered far from the OP's questions!

So getting back to @Neptune then either a RCD or RCBO board would be a worthwhile improvement on your old rewirable fuse boards for lots of reasons, both the convenience of resetting and the additional protection offered by RCD, with the RCBO option slightly better in the event of any fault.

But the board is only one aspect of overall electrical safety:
  1. Make sure all sockets are correctly wired and in good condition
  2. When you have RCDs, check at least twice a year they trip on the 'test' button.
  3. Inspect all of your electrical goods from time to time for signs of damage or stress to the cables, that the cables are properly clamped by the sheath in any plugs, and the plugs are not cracked/damaged or show overheating marks
  4. Check the appliances have the correct fuses fitted to any plugs
  5. Have appliances tested if in any doubt for soundness of earth and insulation
1 & 2 ought to be done under any EICR or board change, but you can follow up yourself with one of the better socket testers such as this:
3-5 would be part of PAT testing in any rented property with landlord supplied appliances, but you can probably manage 3 & 4 yourself, and get a spark in to PAT test for 5 in any situation where you are not 100% sure the appliance (or extension lead) is good.
 
The increased costs you refer to are because of requirements to fit less commonly used types of RCBO, but those are also slowly dropping in price as they are manufactured in greater numbers.

All new technology is expensive as manufacturers need to recoup costs associated with design, development, tooling etc. As demand increases, so does competition and prices drop.
I know why it's happening, and what will make it un-happen.

My point is that it is happening, and we are getting back to the situation from the past where all-RCBO is considerably more expensive than RCCB+MCBs.

This also assumes that people need to have these types of protective devices on their installation.
https://electrical.------.org/wiring-matters/years/2019/77-september-2019/which-rcd-type/

While many people will undoubtedly embrace technology that demands this sort of protection, surely many more people are like Mavis at No. 23 and gain more than adequate protection from Type A devices?
Until Mavis buys a new WM/TD/DW with a variable-speed drive in it.
 
Until Mavis buys a new WM/TD/DW with a variable-speed drive in it.
They won't do it for finance reasons, but the VSD should have insulation monitoring like the PV inverters do.

No ordinary person reviews/changes their CU when buying new white goods, the manufacturers should be constrained to be safe with the common RCD types in use.
 
They won't do it for finance reasons, but the VSD should have insulation monitoring like the PV inverters do.
Is it an insulation issue, or the fundamental nature of the electronics?


No ordinary person reviews/changes their CU when buying new white goods, the manufacturers should be constrained to be safe with the common RCD types in use.
That contraint may be impossible except via banning the use of certain technologies.

And I agree with the first part of that. I'm looking forward to asking the salesman in John Lewis what sort of RCD my new washing machine will need. ?
 
I know why it's happening, and what will make it un-happen.


You originally stated that the decline in RCBO prices was now reversing, which is patently untrue. Comparing apples with oranges (in the form of different types of RCBO) does not make this any less incorrect. Type A RCBOs have dropped sharply in price and Type B & F are also dropping in price, albeit much more slowly due to lower demand.
 
Is it an insulation issue, or the fundamental nature of the electronics?
It is always an insulation issue for RCD tripping! Sometimes the cables damaged, sometimes water in something, sometimes via a person to the Earth.

The issue with VSD, PV panels, EV batteries, etc, is they power thing with smooth(ish) DC, so when it leaks it is leaking DC and not something with enough AC component for a common RCD's transformer to sense as wrong.

What makes matters worse is the sense transformer will be some sort of ferromagnetic material and if there is enough DC its permeability drops as it reaches saturation and it becomes a less-good transformer, effectively making the RCD insensitive to the AC component as well.
 
One pure DC problem. For most faults it is going to be AC and trip the RCBOs first.
No.

The issue is not the failure of Type AC devices to trip with a DC problem. The issue is that they won't trip with any problem if there is a DC component. Which could be always present and not a fault. Just like the way that loop testers use DC to saturate the RCD coil to stop it tripping.
 
No.

The issue is not the failure of Type AC devices to trip with a DC problem. The issue is that they won't trip with any problem if there is a DC component. Which could be always present and not a fault. Just like the way that loop testers use DC to saturate the RCD coil to stop it tripping.
Yes, an A/AC RCBO may not detect the DC, but if that persists for more than the 100ms or whatever for the B delay incomer then the incomer disconnects everything.

So AC-ish fault the RCBO goes and you get single circuit going off.

Sneaky DC fault not tripping the RCBO and it all goes off.

Not ideal, but at a few £100 for type B RCDs it would be an option, just like 30 years ago...
 
You originally stated that the decline in RCBO prices was now reversing, which is patently untrue.
No, what I said was the trend for all-RCBO boards to be declining in price is reversing.


Comparing apples with oranges (in the form of different types of RCBO) does not make this any less incorrect.
It isn't incorrect. If oranges cost more than apples, and your fruit bowl now needs oranges as well as apples then your fruit bowl is going to cost more.


Type A RCBOs have dropped sharply in price and Type B & F are also dropping in price, albeit much more slowly due to lower demand.
They may be dropping in price, but the requirement to put them into CUs (Type Fs anyway - I'm not sure that Type Bs would ever be needed) means that the decining price trend for all-RCBO boards has reversed. The relative cost of multiple RCBOs vs 1 RCCB and multiple MCBs is like it was with Type AC devices when RCBOs started being used.
 
No, what I said was the trend for all-RCBO boards to be declining in price is reversing.



It isn't incorrect. If oranges cost more than apples, and your fruit bowl now needs oranges as well as apples then your fruit bowl is going to cost more.



They may be dropping in price, but the requirement to put them into CUs (Type Fs anyway - I'm not sure that Type Bs would ever be needed) means that the decining price trend for all-RCBO boards has reversed. The relative cost of multiple RCBOs vs 1 RCCB and multiple MCBs is like it was with Type AC devices when RCBOs started being used.

I still can't work you out Soi. I reckon another two porters and I'll have you sussed though.
 
But is it leaking it because of an insulation fault, or because that's just what it does when it is working as designed?
Generally anything measuring less than 1M L+N to E or so at 500V would be condemned as faulty by usual fixed wiring or PAT criteia, so you would only expect to see any significant leak "by design" in specialised cases (that don't just plug in via a 13A socket).
 
This is undoubtedly true but, from a customer's perspective, one circuit out is always going to be much less inconvenient than six - even if it only happens once in 10 years.

I've dealt with a total of two RCD tripping incidents at home. One was caused by an oven element failing and caused almost no inconvenience. The other incident involved repeated trips, which caused the loss of all hot water and I couldn't get a competent electrician to investigate, before finally fixing the problem myself.

Incidentally, it was the latter issue that spurred me (no pun intended) towards the idea of trying to retrain in the industry.
Why is this cited as such an inconvenience? Yes, all the MCB's controlled by that RCD will initially trip but wouldn't you then switch them back on one-by-one to locate the faulty circuit and then just leave that single one out of action until the fault is fixed?
 
Why is this cited as such an inconvenience? Yes, all the MCB's controlled by that RCD will initially trip but wouldn't you then switch them back on one-by-one to locate the faulty circuit and then just leave that single one out of action until the fault is fixed?

For the very reason I stated in that post:

Repeated trips when a fault can not be easily identified, causing the loss of half the circuits each time.

This isn't something the average household will experience often, but the hassle caused by irate tenants in such an eventuality might lead to a landlord to questioning the real value of that £120 saving.
 
UPDATE: The consumer unit was replaced this week. I am waiting a new EICR that was completed as part of this. Here is a picture of the finished article and I would appreciate your feedback.
The electrician said that the gap was due to the difference in size of consumer units and I would need to make that good. I assume that is normal practice.
Can I please have some suggestions on how I can finish that off please?

Thanks again.
 

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UPDATE: The consumer unit was replaced this week. I am waiting a new EICR that was completed as part of this. Here is a picture of the finished article and I would appreciate your feedback.
Main thing is it's safe. And if a fellow sparks has a silicone fetish who am I to judge?!
Can I please have some suggestions on how I can finish that off please?
Basically construct something with wood to cover it.
What comes to mind is a batten on the top of the boxing lid (carefully attached to miss cables and so the lid is still removeable) and a bit of hardboard attached in turn to that extending up in front of cables.
OR two triangle side pieces screwed to sides and a bit of hardboard on the front of them.
 

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