How to find current electrical load to my home

bren1916

Hi All,

I'm considering installing an electrical wall charger in the coming weeks but having difficulty assessing the load supply to my 1960's-built home. Tried looking at meter & CU but don't see anything other that it's a single-phase supply. Any way of finding out other than waiting to call the supplier next week?

TIA

Bren

10-10-20

A photo posted here showing the meter and CU might result in some responses.

denismc

In your consumer unit have a look at the the main breaker or fuse, 63 amps is pretty common, it may be less if your house is old.

bren1916

Thanks, the main CU has a 63a fuse, as has the secondary CU in extension so can anyone advise

what would the load be? Cheers

denismc

63x230 gives 14.5 kW which is plenty for charging EVs.

If you have an electric shower you will need to install a priority switch or get a charger that can do load balancing.

meercat

Which of these is your main board

the fuse on your abb board should be replaced (they cause issues)

there doesn’t appear to be Mcb protection for the cable to your sub board

you have an electric shower that may cause load problems if you install a car charger

what’s the 20amp contactor for

post a photo of your meter cabinet and associated wiring to determine cable sizes if you are adding additional loads

im sure you know only a rec is permitted to do this type of work

bren1916

Which of these is your main board - Blank one (Not the ABB board)

the fuse on your abb board should be replaced (they cause issues) Ok - been there since 2012 with no issues so far but will keep in mind

there doesn’t appear to be Mcb protection for the cable to your sub board

you have an electric shower that may cause load problems if you install a car charger - Likely go for the load balancer this is the reason for the original query

what’s the 20amp contactor for - lighting timer

post a photo of your meter cabinet and associated wiring to determine cable sizes if you are adding additional loads - no additional loads will be added if not needed

im sure you know only a rec is permitted to do this type of work - it'll be RECI I just want to know what I have before they come out to quote

meercat

https://www.boards.ie/discussion/comment/120210842#Comment_120210842

If it’s a 1960s house then the mains cables may not be sufficient to take the extra load if they haven’t been updated. Post a photo of your meter cabinet and associated cables

bren1916

Incoming cables to meter box, one in the black sleeve is the feed to the sub-board

meercat

https://www.boards.ie/discussion/comment/120212417#Comment_120212417

it’s still not clear what size you main cables to distribution board are

Without checking,I’d say that black cable is undersized if it’s feeding your sub board considering there’s an electric shower fed off it. There doesn’t appear to be any earthing on the outer sheath either

the black esbn main fuse is most likely 63amp as this is the older cutout.sometimes a hrc 60amp fuse is used. I’m surprised they didn’t upgrade it to an 80amp cutout when they replaced the meter.

bren1916

Ok thanks for the comments, the electric shower is fed off the main board and so that black cable is not feeding a shower. Given the 14.5kW supply mentioned above, if I go for a load balancing charger I should be ok and not require anything over and above what I already have? The charger location will be directly below the main board on the exterior so no issue with cable runs, etc.

kirk.

https://www.boards.ie/discussion/comment/120214464#Comment_120214464

You cant judge the supply by the main fuse in a board

Anyone can upgrade an old installation to a 63a board

I would usually go by 12 /16 KVA etc , the esbn supply size

Some of the older installations would be lower again

bren1916

You’d think the bill would just have this information alongside the mprn. So anyone know how to definitively find out what the supply would be? Would esbn even have this info?

antoinolachtnai

ESBn should be able to tell you if the supply is nominally 8, 12 or 16 kVA. But this is no substitute for an assessment by your electrician.

bren1916

ESBn confirmed it’s only 8kVa at the moment, looks like I’ll need to apply for an increase to to 12

kirk.

https://www.boards.ie/discussion/comment/120230525#Comment_120230525

I'm guessing that's the large DZ 35amp Esbn fuse there then for 8kva , haven't heard of the term 8kva used before

Some of the older supplies used to have a 25amp Esbn fuse

Not sure what happened when the electric cookers came in back in the day .You'd run a few cooker rings on a 25amp fuse anyhow