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#136905 - 05/12/03 05:12 AM Irish consumer unit
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Posted for DJK from Ireland:

This is from a 4 bedroom house. The top row are 10 amp (Lights), Cooker is 32amp, 20amp (Immersion) 10amp (Boiler + Pumps [heating system controls, for some reason the entire heating system.. boiler,
pumps, timers etc.. is connected via a 5amp double pole switched spur as the only item on that radial circuit.

The black marks are just dust. There were a LOT of cobwebs

It's an installation dating from the 1970s originally. Although the age of this unit isn't quite clear. It does pre-date current RCD requirements as only the sockets are RCD protected.

We're adding more lights so that top row will be a lot fuller and as they're "touchable" and include plug-in switch controlled free standing
lamps, we're going to RCD protect them. Should be easy enough there's still space on the board

This unit is VERY typical though. Older ones are identical the only difference being that the breakers would all be neozed (or even diazed) fuses.

(note the main fuse!)

[This message has been edited by pauluk (edited 05-12-2003).]

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#136906 - 05/12/03 05:51 AM Re: Irish consumer unit
djk Offline

Registered: 12/26/02
Posts: 1269
Loc: Ireland
Thanks paul

Just to clarify the bottom row are all 20A MCBs.

& the cooker is actually 40A not 32

Just stumbled upon an interesting document: shows how seriously the ETCI (ElectroTechnical Council of Ireland) are taking RCD protection! Looks like we'll have consumer units full of the things if this proposal is accepted and made manditory in the wiring rules.

TC5: ETCI Safety Committee

TC5 is now focused on delivering on commitments detailed in its Strategic Plan 2003 - 2005, as follows:

* Complete the development of an intelligent RCD Tester (that can be plugged into any 13Asocket) that can be easily used to activate the RCD (on the distribution board) and determine if it is operating correctly (@30mAin less than 0.3 seconds). Time to trip will be indicated.

* Develop a new Guide on "The Principles of Electricity and Electrical Safety" and an associated training course. The guide will explain the basic principles of electricity, how it can harm and how to
prevent such harm. This Guide should, when completed, lead on towards the present Guide on "The Management of Electrical Safety at Work".

* Develop a Database for the recording and analysis of electrical incidents (fatal and non-fatal) and have it available on the ETCI website. It will be populated with a significant amount of information from past incidents (details of electrical fatalities from 1929 still available) and will detail the precautions that could and should have been taken to prevent or minimise the consequences.

* Recommend (to TC2) that all 230/400V electrical circuits be protected by independent RCDs, i.e. sockets protected by one RCD, lights by another
and fixed installations by one or more other RCDs. Smoke detectors and associated emergency lighting should make this proposal easier.

* Other work as appropriate and possible, e.g. study of fire incidents and keeping abreast with international developments (ISSA, ACOS, IEC)

(From an ETCI document available online)

[This message has been edited by djk (edited 05-12-2003).]

#136907 - 05/12/03 08:25 AM Re: Irish consumer unit
C-H Offline


Registered: 09/17/02
Posts: 1508
Loc: Stockholm, Sweden
Does one dare to predict an explosion in the sales of RCBOs in Ireland?

#136908 - 05/12/03 08:52 AM Re: Irish consumer unit
Texas_Ranger Offline

Registered: 12/17/01
Posts: 2349
Loc: Vienna, Austria
True, there are plenty of spaces in the upper row, should get an RCD and 5 more breakers in. The lonely Neozed fuse looks weird, I only know them in groups of 3, at our hardware store they don't even sell single pole Neozed elements.
The number of breakers is quite high for such a house, as I mostly deal with very old wiring I'm still used to a scheme like 2 or 3 large rooms lights+receptacles on one circuit (for example our apartment: circuit 1: Bedroom 1, living room, bathroom. Circuit 2: Bedroom 2, hallway, kitchen and toilet (usually not located inside the bathroom but in a separate room). Circuit 3: Dishwasher. Circuit 4: Washing machine. 1 and 2 are 13A, 3 and 4 are 16A. All breakers 1+N, everything protected by 1 30mA RCD. 20A main fuse out in the stairway (there's usually one big main fuse box for all apartments on each floor), wired with 10mm2), maybe some 16A 3ph circuits for range etc. We never had a breaker trip from an overload.

#136909 - 05/12/03 09:28 AM Re: Irish consumer unit
djk Offline

Registered: 12/26/02
Posts: 1269
Loc: Ireland
Well this is serving:

Kitchen : 12 (6 X 2-gang) socket outlets & 4 (2 X 2-gang) dedicated to a utility room (Washer, Dryer and Dishwasher & spare)

Total : 10 points (all double)

4 Bedrooms have 2 X 2-gang each
Total 8 points : all double

2 Reception rooms 2 X 2-gang each
Total 4 points : all double

1 Dining room (3 X 2-gang)
Total: 3 points: all double

2 Hallways (1 X 2-gang)
Total 2 points : all double

& 1 outdoor socket (single gang)

Grand total: 28 points of which 27 are 2-gang.


every living area room has 1 centre light & at least 2 side lights.

Hallways have more "artistic" fittings (2 each)
Kitchen has 10 large 220V recessed spots
Bedrooms 1 main centre light each.
Bathrooms (3) have 1 ceiling lamp each, mirror lighting & a 40W fan
& there's outdoor lighting..

Other (dedicated circuits):

1 X Oven 6010W (max load only during cleaning cycle)
1 X Induction Hob: 4200W

10mm2 cable runs from the 40amp breaker to 1 X 32 amp & 2 X 16A breakers on a mini-distribution board in the kitchen.. from there more heavy cable runs to the cooker and hob control switches. The hob requires weird fusing arrangements!

1 X 32 amp = the oven
2 X 16 amp = each half of the hob!

The manufacturer provided an own branded multi-pole isolation switch & recessed wall box. I know it would be possible to double up and use 1 X 32 amp but I guess ignoring manufacturers instructions is not advisable.. there may be a good reason & they went to unusual lengths..

I think it's a comprimise sollution for something that is normally used on 380/400V 3-phase in France.

The hob's actually very intelligently interlocked so that the individual plates can consume up to 2.9KW each but it will automatically turn down the heat / cycle the power on and off if you turn on more than the total wattage.

So as one plate turns up towards 9 the other one will adjust from 9 back to 7. It also cycles on lower settings so that, at lower tempratures, each plate is switched in and out at different times and not all together.

It means it can boil a large pot of water in about 1min30sec on high! Induction = very little energy loss!

(single phase 220-230V)

Immersion Water heater:
2 - 3 KW

Gas fired system circulation pumps and controls:
less than 5amp load.

For some reason it also has a 5amp fused spur feeding the doorbell and some amplifiers for distributing tv signals around the house.

So you can see why it needs quite a few MCBs

[This message has been edited by djk (edited 05-12-2003).]

#136910 - 05/13/03 01:22 AM Re: Irish consumer unit
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
You may well be right about the hob being designed for the supplies in some French houses.

For regular domestic service, EDF bases the standing charge on the rating of the service. Three-phase is common, but I've seen a lot of homes in France with a main breaker set for just 15 or 20A per phase, so this sophisticated hob would certainly be helpful in those situations.


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