Only 2 brands for domestic type A rcd/rcbo + type 2 spd in board??

[Mattja]

Looking around I'm wondering if I'm going mad. Would have thought type 2 spd next to main switch and type A (not type AC) rcd/rcbos would be the standard everyone should be looking for now (even if it's just recommended and not strictly required in domestics). But only Wylex and Schneider seem to supply the parts?

Anyone else found a supplier for both these features from any other brands or is this it?

 

[Thrashman]

My issue is continuity of service, if an SPD relies upon the dno fuse and for whatever reason it shorts out then you will loose the total supply and will be non compliant.
The extra £3 for mcb sounds okay tho.

TBF, that’s a good point and totally agree Ian, Fitted one earlier this week with SPD and personally did opt for the 32a mcb as was a 100A supply fuse , may consider this for 60-80a aswell. Also fitted an AXIOM earlier this week with SPD and manufactures instructions required ocpd via mcb, maybe fusebox will require this soon aswell.
but to answer the ops question , the brand is an option with type A rcbo s and type 2 SPD , ( with optional mcb ocpd ) and is a good build quality at a reasonable cost . ??

 

[SJD]

The SPD modules are marked with a fuse symbol, and 125A.

According to the website below, "FuseBox SPDs don’t require a backup fuse or MCB if the normal supply current is less than 125A which in the majority of domestic applications is the case."

http://www.serenelectrical.co.uk/wp-content/uploads/2019/01/Seren-Surge-Protection.pdf

 

[Ian1981]

The SPD modules are marked with a fuse symbol, and 125A.

According to the website below, "FuseBox SPDs don’t require a backup fuse or MCB if the normal supply current is less than 125A which in the majority of domestic applications is the case."

http://www.serenelectrical.co.uk/wp-content/uploads/2019/01/Seren-Surge-Protection.pdf

By relying on the DNO fuse for short circuit protection, How do they comply with 534.4.5 and 534.4.5.2 then?

 

[AJshep]

It really depends on the SPD whether it needs an OCPD.
Its my understanding that SPDs are designed to fail open circuit. Pretty sure they are manufactured with a small soldered joint which is spring loaded, this is designed to melt under high fault currents and break the contact.

 

[SJD]

I was going to look inside one, to see exactly what is inside, but can't seem to open the plastic casing without risking damaging it (it is in a new Fusebox CU yet to be installed).

 

[Ian1981]

It really depends on the SPD whether it needs an OCPD.
Its my understanding that SPDs are designed to fail open circuit. Pretty sure they are manufactured with a small soldered joint which is spring loaded, this is designed to melt under high fault currents and break the contact.

I’ve been told this by Robin from Dehn.
However Kirsty from surge protection devices says the opposite.
Both sit on the jpel/64 section D apparently.....
[automerge]1587898727[/automerge]

I was going to look inside one, to see exactly what is inside, but can't seem to open the plastic casing without risking damaging it (it is in a new Fusebox CU yet to be installed).

Do it anyway haha

 

[Baddegg]

Hi Ian,
Yes you are correct in saying their is no internal ocpd but they are rated at 125a which for most domestic installs with 60 and 80amp cutouts, the DNO fuse is acceptable for last resort OCPD with less than 250mm 6mm cable in total on the internal LNE SPD cables. For an extra £3 a 32amp mcb can be added to supply the SPD to give protection aswell ?

Fit loads of 6 way boards in terrace houses round here and to fit the 32a for the spd means going up to a 10 way board.....Havnt found an 8way fusebox yet??

 

[pc1966]

If the SPD has a "fail flag" on display then almost certainly it has the spring loaded solder joint as a thermal disconnect mechanism inside. Also the MOV type (as normally used for type 2 and some type 1 SPD) tend to fail open, perhaps spectacularly so if they get a big direct hit but you probably have other concerns at that point...

I'm sure somewhere on YouTube I have seen a video with one of them taken apart that shows this but don't remember who did it.

 

[Thrashman]

Fit loads of 6 way boards in terrace houses round here and to fit the 32a for the spd means going up to a 10 way board.....Havnt found an 8way fusebox yet??

Fusebox did an 8 way and then made the same enclose metal cutouts wider and a larger din rail to accommodate 2 more ways without having to re manufacture all the enclosure ( so the old 8 way enclosure is the same size as the new 10 way) . 6 rcbo s / 1 mcb for SPD and 3 blanks allowing for future upgrades would do the job.

 

[Baddegg]

Fusebox did an 8 way and then made the same enclose metal cutouts wider and a larger din rail to accommodate 2 more ways without having to re manufacture all the enclosure ( so the old 8 way enclosure is the same size as the new 10 way) . 6 rcbo s / 1 mcb for SPD and 3 blanks allowing for future upgrades would do the job.

They would if they fitted in place of an old wylex board that you’ve taken out ?

 

[Gavin John Hyde]

Lewden and the rexel own brands offer Type A
BG offer type A rcds, possibly rcbos aswell. I often swap an ac rcd for a type a when fitting ev chargers in bg boards.
As mentioned already Fusebox supply type A's
Quick look on cef shows Proteus, MCG, M2 all doing type A
Rolec also do them, usually for there own ev or caravan hook ups.
Plenty of options out there and if you cant find one for your make of board then you can always route a circuit through a standalone module.

 

[Dobes_88]

Contactum is my go to and offer Type A RCBO's for a reasonable price also.

 

[SJD]

I was going to look inside one, to see exactly what is inside, but can't seem to open the plastic casing without risking damaging it (it is in a new Fusebox CU yet to be installed).

Well I now have a failed Fusebox SPD, so took a look inside. It failed due to mechanical damage, not electrical. The solder joint has broken, so the green flag springs back, revealing the red "failed" flag behind it.

 

[pc1966]

Well I now have a failed Fusebox SPD, so took a look inside. It failed due to mechanical damage, not electrical. The solder joint has broken, so the green flag springs back, revealing the red "failed" flag behind it.

Can you show us the other side (MOV part) as well?

 

[SJD]

The other side is completely encapsulated in some white solid (non-rubber) potting compound, so there is nothing to see.