Hi all,
Just planning a sub main to an outbuilding .
It will be 80 metre run, buried direct on a 63amp fuse .
So I am thinking of running 25mm swa but just been doing my calcs on whether I can use armour as Cpc. The outbuilding is going to be TT so no need of a bonding conductor on the...
I was replacing a socket that had a cracked face and as I took said socket off I noticed the armour was earthed by using BS951 clamps. I wasn’t expecting to see any earthing of the armour as the SWA was in a conduit drop to the socket.
I’ve never seen it done like that before but now I walk...
Hi, someone has ordered Steel Tape Armoured cable instead of SWA. Can I use this armour as a CPC the same as SWA or not and if so is there a table so that I can check the figures.
Secondly, correct me if I am wrong but 3ph with a reduced neutral should only be used on a balanced load ie a...
If cpc core is present i.e. it's either 5 core three phase or 3 core single phase — is a banjo connected with a brass screw into steel trunking adequate to earth the armour(provided trunking is earthed to the earth bar)? Or would you put fly leads in between then a fly lead to an earth bar?
Thanks.
As the title says, I am looking for a recommendation for an enclosure and gland arrangement to electrically isolate or divorce the earth/armouring of a two core SWA supplying an outbuilding/shed. The supply to the property is overhead TT, so DNO provide phase and neutral only, a sub 20 ohm rod...
In a former life on another forum as well as this one.... there were a whole heap of downloads that people had done as ready-reckoners for things like Cu eq for various armour sizes, R1R2 values on lengths.. useful stuff. I think I might even have generated some myself.
Anyone have any...
Hi All, hope your all well.
I was hoping if I can please get some advice in regards to SWA. In Particular using SWA as CPC. Cable size 95mm2
I have a table for SWA which shows various information, in the last two columns it shows the "resistance of steel armour under fault conditions at 70...
Armour not CPC.
By the letter of the regs 2.5mm is acceptable as the DB offers both mehanical and corrosion protection.
Just seems a bit puny on a 10mm SWA, what about a much larger cable?
Can some of the boffins explain why 2.5mm is deemed acceptable.
Cheers
A friend at work asked me to take a look at the electrics in his shed, RCD would occasionally trip out, turned out to be a very loose neutral going in to the RCD.
One thing I did notice though was that the 10MM2 SWA entered through the back entry point of both the shed & house CU and neither...
At the origin the installation is TT.
Plan is to install a submain to a new db. Not carried out all the calcs yet, but my question is does the swa require an earth conductor in the cable.
Basically planning on running a phase and neutral or perhaps even 2 x phases and neutral.(the cable will be...
Hi all
I am after some help/Advice if possible please
A SWA sub main Distribution circuit has been given a Code 2 Rating on a recent EICR due to a high Zs of 2.8 ohms. The cable is 180 metres long and runs underground in ducting.
The Install is from a few years ago when a new Substation was put...
I have run 6mm t and e through the house from the db in the garage on a 32 amp mcb which is rcd protected. the 6 mm cable then goes into the back of an ip66 rated JB on the side of the house. i then intend to run 2 core (live and neutral) 6mm swa up to a workshop using the armour as earth.
my...
I have installed a TT system at my garage, and it is fed via 10mm 2 core armoured cable, does the armour of the cable have to be earthed via the supply tncs side or can it be glanded and earthed the garage side (TT).
Anyone know the regs ?
Thanks
Hi - various discussions we've had are summarised in this Voltimum information paper. Interesting for me was they effectively say main protective bonding in PME installations should be external to the cable, due to heating risk. I'm still digesting this myself ...
The earthing functions that can...
Just after A bit of advice regarding a load of swa cables into dist board. What's people's preferred methods / good practice regarding banjos fly leads etc. Banjos inside?? If multiple cables are using armour as cpc is it considered bad practice to use 1 fly lead between the two Banjos??? Is it...
Hello all,
Quick bit of background, factory maintenance spark for 20+ years, covered some installation work over the years but not done a great deal of testing. New lines and cells are being installed over the next few months and all installation is being done in house. Decided it is time to...
Hi guys,
I am running a supply to an outbuilding that requires a 22m run from the Main CU (in the garage) to the CU in the outbuilding, at the Main CU it will be a 40A MCB supplying an 63ma RCD protected sub board which will then supply:
6A type B MCB for 12 downlights and an extractor fan
32A...
Doing EICR on a HMO, DB feeds a Consumer Unit in each room. The feeds to each consumer unit seem to be SWA however the armour is not visible/accessible at either the consumer unit or the DB - it seems to have been cut out behind the DB which is inaccessible.
The cable is buried in the walls and...
Hi all, long time reader first time poster. I am an apprentice that has mainly done domestic work, but more recently we have been doing commercial jobs (which i much prefer lol), i do really enjoy electrical work and I'm keen to learn more, which means i ask a lot of questions.
The last couple...
I know it's late and the lap dances are still open , so i will wait till tomorrow for any replies . Does anyone have resistance per meter tables for steel armour 90degree thermosetting ,can't find it anywhere . Ta
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