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Identification help: Is this RCBO Type A or Type AC?

 
Electricity, Tariffs, Monitoring, Electrics & Providers
Last Post by Transparent 5 months ago
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Mars
 Mars
(@editor)
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Topic starter 24/03/2026 2:51 pm   [#2905]

I've formally started my journey into learning more about domestic electrics and I'm currently looking at our consumer unit and garage DB to see if our existing protection is Type A or Type AC. I know Type A is the modern standard for anything with electronics/inverters, but I’m struggling to be 100% sure based on the markings.

Looking at the RCBO in the image below labelled "Socket", can anyone confirm from the markings on this MCG RCBO if it is a Type A?

RCBOs in garage

 


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JamesPa
 JamesPa
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24/03/2026 5:42 pm  

Posted by: @editor
↑

I've formally started my journey into learning more about domestic electrics and I'm currently looking at our consumer unit and garage DB to see if our existing protection is Type A or Type AC. I know Type A is the modern standard for anything with electronics/inverters, but I’m struggling to be 100% sure based on the markings.

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MK4
 MK4
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26/03/2026 9:13 pm  

@editor 

Could perhaps the following pictures be of any use to you? 
One is in english but blurry, the other is in greek but clearer (so that you can more easily discern the markings per type).

I was not able to see any of these markings in your photo, may be if you pull the switch down there are markings behind the lever….

IMG 3357
IMG 3356

 



   
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Transparent
 Transparent
(@transparent)
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Posts: 3371
31/03/2026 11:11 am  

Posted by: @editor
↑

Looking at the RCBO in the image below labelled "Socket", can anyone confirm from the markings on this MCG RCBO if it is a Type A?

Apologies for arriving here late!

From what we can see of that RCBO, there is no indication of its Type.

The 'B' in 'B16' refers to the curve which defines how fast it responds to over-current faults.
Beware of Screwfix who often describe trips incorrectly!

It's possible that there is writing we can't see hidden behind the toggle lever, beneath the words "Test Monthly".

RCD type

 

One of my gripes is that simply isn't sufficient room on the 18x47mm visible part of a single-module-wide trip to tell us all we need to know.

Even if it were labelled with the relevant symbol for its Type, we'd still need to remove the front cover to see if it's uni- or bi-directional.

 

Could you take off the CU cover and post another photo here please?


This post was modified 5 months ago 3 times by Transparent

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