100mA time delay rcd

[Paul17176]

Plenty of other options to install it wothout RCD protection.

Very true, will look to convince him it's the better option.

Thanks for your help fellas

 

[Paul17176]

Buried SWA or buried Earthed metallic conduit for example.

Hmm, hadn't considered a buried SWA. Thanks

 

[davesparks]

A 30mA time delayed RCD wouldn't help as the regulation requires a standard 30mA RCD.

Some foil screened (but not all) cables comply with the requirement for an earthed metallic surround/sheath or whatever. FP200 is one example of this

 

[Leesparkykent]

Hmm, hadn't considered a buried SWA. Thanks

The manufactures instructions say its 1700w so you could bury a 1.5mm 3core SWA and put it on a 10amp MCB. And a 1.5mm SWA isn't going to be the end of the world to bury lol

 

[Leesparkykent]

A 30mA time delayed RCD wouldn't help as the regulation requires a standard 30mA RCD.

Some foil screened (but not all) cables comply with the requirement for an earthed metallic surround/sheath or whatever. FP200 is one example of this

Just out of interest dave how would you earth the foil screen in FP200

 

[davesparks]

Just out of interest dave how would you earth the foil screen in FP200

By connecting the cpc, have a look at the manufacturers information. I assume you've never worked with FP200? It has a bare cpc much like T&E which is in contact with the foil screen throughout its length, this has been tested as suitable for this type of protection as detailed in the manufacturers information

 

[Leesparkykent]

By connecting the cpc, have a look at the manufacturers information. I assume you've never worked with FP200? It has a bare cpc much like T&E which is in contact with the foil screen throughout its length, this has been tested as suitable for this type of protection as detailed in the manufacturers information

Yes just looked it up FP200 gold or FP200 plus meets the requirements of the nail penetration test and the CPC is in contact with the foil screen. I have used it yes but never knew it complied in this manner. Handy bit of information for the future though lol. Cheers dave

 

[Deleted member 26818]

Don't think that FP200 does satisfy the requirements.
The requirements specifically state that the cables should be to BS8436.
A cable such as flexishield for instance.

 

[TJ Anderson]

I just copied this info below on 8436 Cable:
The cores are intended for use as LINE, NEUTRAL & EARTH - so its essentially similar to Twin & Earth & other 2core + CPC cables. (the cpc is in constant contact with the aluminium foil shield) The XLPE / LSF Low Smoke Flume shielded construction means Flexishield offers fire extinguishing & EMC properties, & is fully recognised by BS7671:2011
Harmonised core colours (Brown/Blue) & white outer-sheath.


This cable is one of the very few to meet the demanding requirements of BS 8436 - & it actually exceeds the requirements of a huge number of lesser cables, e.g. BS6004 PVC cables such as 6242y Twin & Earth. Unlike those, its sheath isn't harmed by UV rays, polystyrenes, creosote, oils etc. - meaning it can replace standard cables, both indoors & out.
Due to its particular qualities, & its combination of LSF XLPE insulation & covering, the cable is extensively used in modern buildings. In fact, its often used to wire listed, prestige & vulnerable buildings in their entirety - completely replacing conventional PVC covered cabling.


If you're not familiar with the likes of Flexishield, this cable has quite specific properties... It's encased in a aluminium foil tape sheath, which makes the cable beautifully easy to work with - its uncannily light for its size, its highly dressable, & termination is so quick & easy it spoils you for all other cables! No requirement to ferrule or gland off - just ring with a Jokari etc. or even a knife, & the outer sheath breaks off. Even a DIYer will be terminating like a pro!
The aluminium sheath of Flexishield has been designed to meet the stringent requirements of BS8436 - most notably, that Standard's testing against piercing of the cable's outer sheath by the likes of nails & screws, causing the guaranteed operation of the protective device.
Therefore, cables passing the regimes of BS8436 (& there are very few) are qualified for use, unprotected & buried in walls at less than 50mm from the walls surface - even outside the 'safe zones' & without 30mA Residual Current Device protection!
Other than BS8436, the ONLY other cables permitted for such installation are MICC (Pyro) or SWA (SteelWiredArmour) which are hugely more time consuming to install & terminate - & both require specific glands to be fitted at every point.


All of which makes BS8436 cable uniquely useful. Whether its to completely wire an entire building, or simply to 'get-you-out-of-jail' on those unexpectedly awkward circuits where compliance with BS7671 couldn`t otherwise be achieved, Flexishield is often the only choice. Its not always desirable, or possible to protect every circuit, or extension of a circuit, with a 30mA RCD. In many cases, use of BS8436 Flexishield removes the requirement. Every smart spark should carry some on his van!

 

[Risteard]

couldn't find a time delayed 30mA rcd

Such a beast would be of little use for providing additional protection. It wouldn't trip sufficiently quickly to reduce the risk of electrocution if it was time-delayed!