Is this RCD underrated?

[Dave Robinson]

Looking to add two circuits for a workshop & an outside socket, but in looking at my CU there are four MCBs; (one 32A ring, two showers 40 & 45 and 32 cooker) into an 80A 30mA RCD. I appreciate the likelihood of running both showers, oven, washing machine and tumble drier simultaneously is unlikley, but is this common practice?
We have experienced it tripping when all appliances are on & our two boys are growing=increasingly showering! - probably only going to get worse.

 

[telectrix]

you need a bigger CU.

 

[Pete999]

Diversity Rules OK

 

[Toneyz]

Looking to add two circuits for a workshop & an outside socket, but in looking at my CU there are four MCBs; (one 32A ring, two showers 40 & 45 and 32 cooker) into an 80A 30mA RCD. I appreciate the likelihood of running both showers, oven, washing machine and tumble drier simultaneously is unlikley, but is this common practice?
We have experienced it tripping when all appliances are on & our two boys are growing=increasingly showering! - probably only going to get worse.

Is this RCD the main switch?

 

[David Prosser]

Heung-Min Son, now he's underrated !

 

[rapparee]

Heung-Min Son, now he's underrated !

An Olympic diver

 

[Dave Robinson]

No, main 100A switch and two 6A non-RCD'd MCB for lights/smoke alarm upstream.

 

[Wilko]

Looking to add two circuits for a workshop & an outside socket, but in looking at my CU there are four MCBs; (one 32A ring, two showers 40 & 45 and 32 cooker) into an 80A 30mA RCD. I appreciate the likelihood of running both showers, oven, washing machine and tumble drier simultaneously is unlikley, but is this common practice?
We have experienced it tripping when all appliances are on & our two boys are growing=increasingly showering! - probably only going to get worse.

Hi Dave and Welcome to the Forum
I wouldn't install 2 showers on one RCD. If they ever go on together that will be close to full capacity and a toaster and kettle will see you OTT.

 

[Dave Robinson]

Well, yes, it didn't seem right, but someone disagrees with both of us and has done! Install was before we moved in.
Resolve with an independent 45A RCBO for each shower straight after the main switch, or anyone have a better idea?

 

[Baddegg]

Rcbos better option on non rcd side Dave...

 

[Flanders]

As above your set up is not ideal .If its an RCD and not and RCBO then that would only trip if there where a fault as in to much earth leakage, it will not trip out if overloaded

 

[DefyG]

Just move one over onto a RCBO and save the cost of a second RCBO!

Long term would be better with independent RCBO's as potential problems would not affect other circuits.

 

[Flanders]

What power are you looking to add to work shop? As others have said you could just add rcbos for your addional circuits, depends on the make of you board though as some rcbos may cost the same a new consumer unit

 

[Dave Robinson]

Sounds like a plan, thanks all!

 

[Dave Robinson]

For the workshop, I think I'm going to run an independent master breaker from the main fuse in the house, then SWA out to the workshop and an independent CU in there.