Suitable RCBO for EESS install

[Danny H]

I mistyped 'I can see' meant to type Can't.

 

[DPG]

I mistyped 'I can see' meant to type Can't.

We've had worse don't worry.

 

[mainline]

I work for a renewable energy company that install PV systems and battery storage and one of the lads mentioned that the tutor on the PV and battery course said that RCBOs are not suitable as they are not Bi directional. Since then i've been trying to get confirmation or any info from manufacturers on this and getting no joy, as a rule we install a new DB but on some retro fits an RCBO would be ideal as installing a separate board would cause to much disruption. Very Frustrating.

16 A 1 Mod DP Compact RCBO 6kA B Curve 30mA Type A - M2 Electrical

Available in 6 A to 40 A 30mA, Type A tripping sensitivity800 mm long Neutral CableSwitched Neutral as standardReduces time for insulation resistance testingBi-directional

m2electrical.co.uk

 

[pc1966]

@mainline has pointed to the M2 RCBO that explicitly say they are bidirectional, I also know the Wylex/Crebtree compact RCBO will be OK as they are also neutral-switching and fully isolated on the output when tripped - they allow you to IR test on the load side without any issue.

Sadly so many companies now have as "data sheet" that has damn-all information of any technical nature.

 

[Danny H]

Thanks mate, I neglected to say we only used DP RCBOs,or SP an N but some manufacturers dont specifically state its Bidirectional. like you say though mate some companies are better than others,

 

[GalaxyTS]

Hi all....just catching up on the subject of bi-directional devices, having recently undertaken the EESS course. I usually fit Elucian boards but don't have an answer on whether their RCBOs are bi-directional at the moment, however I have just downloaded a Proteus datasheet which clearly states that their Type A devices ARE bi-directional

 

[GalaxyTS]

Hi all....just catching up on the subject of bi-directional devices, having recently undertaken the EESS course. I usually fit Elucian boards but don't have an answer on whether their RCBOs are bi-directional at the moment, however I have just downloaded a Proteus datasheet which clearly states that their Type A devices ARE bi-directional

Update....have also just had confirmation from WCED that their full range of RCBO, RCD and MCB are bi-directional and suited to solar/EESS installs

 

[pc1966]

Relating to this discussion I saw this today:

BEAMA Technical Bulletin - Connection of Unidirectional and Bidirectional Protective Devices

www.beama.org.uk

Basically it says if they are marked line/load or have direction arrows they are not suitable, which seems to rule out the Wylex compact RCBO as they have direction arrows on them.

 

[happysteve]

Relating to this discussion I saw this today:

BEAMA Technical Bulletin - Connection of Unidirectional and Bidirectional Protective Devices

www.beama.org.uk

Basically it says if they are marked line/load or have direction arrows they are not suitable, which seems to rule out the Wylex compact RCBO as they have direction arrows on them.

Electrium / Wylex / Crabtree now have a declaration of conformity that states that their single module compact RCBOs are bi-directional:

Direct link to PDF: https://docs.electrium.co.uk/Documents/NHXS1B06_Declaration of Conformity Bidirectional RCBOs.pdf

Link to web page (for B6 Wylex RCBO) which has a link to the above PDF, if the link above doesn't work directly

Just for good measure, a couple of screenshots of the document:

Hager seem to do bidirectional RCBO (Type A RCD) with C-curve overcurrent, e.g. ADC932R... unlike their single pole solid neutral B-curve ones (e.g. ADA332G, which they do not state as bidirectional) the C-curve ones are 2P. I've never seen one in the wild, though.

There is a vague reference to a Fusebox bi-directional RCBO "coming in 2024" from one of the online wholesalers who sell their stuff, but I've not heard anything else.

For those interest in the issues about bi-directional/uni-directional devices, eFixx did a bit (involving a whiteboard!) about 1 hour 29 seconds into this video:

Suspect the upcoming draft for public consultation (8 May - 5 June 2024) is all about this:

https://electrical.------.org/bs-7671/updates-to-18th-edition/ (the forum blanks out part of the address, you'll need to replace the dashes with "the iet" without the space)

Hope the above is useful!

 

[Resu]