No banjo on SWA cable glands in junction box

[sealtt]

The outdoor junction box connecting 2 ends of SWA cable and 1 light cable got damaged so I opened it up to transfer everything to a new box. Upon opening it I noticed the glands did not have banjos on them, as such wouldn’t this mean the steel armour is not earthed on at least a portion of the cable? Even though the core of the gland is brass, this wouldn’t do the trick as the junction box is plastic?

Am I missing something here or should banjos and earthing have been added at the install?

[M22s]

Google was little help - fairly sure this is not right......

[Alucidnation]

sealtt said:

The outdoor junction box connecting 2 ends of SWA cable and 1 light cable got damaged so I opened it up to transfer everything to a new box. Upon opening it I noticed the glands did not have banjos on them, as such wouldn’t this mean the steel armour is not earthed on at least a portion of the cable? Even though the core of the gland is brass, this wouldn’t do the trick as the junction box is plastic?

Am I missing something here or should banjos and earthing have been added at the install?

Just because it isn't there specifically.

[ruggedscotty]

You would need to check where the cable originates from and where the cable terminates, if there are banjos at the other ends and these are earthed then fine, The wire armour would thenl be earthed through the earth core through the cable. Still needs to be checked as you have seen you may not be earthed, If its a two core SWA then no it isnt right as that 2nd section of swa isnt grounded. Id be wary. it all depends on what you are feeding and if requires an earth. but the missing banjo's are a cooncern



2-Core SWA Armoured Cable is live and neutral for Class II and Double Insulated appliances which do not need earth connection.

3-Core SWA Armoured Cables are live, neutral and earth, unlike 2-Core. Three core cable is for Class I or Single Insulated which must have earth connections.

The armour should be earthed but it should not be relied upon for the earth conductor from source to point of use if the equipment being supplied requires an earth connection.



https://etechcomponents.com/steel-wire-armoured-ca...

[sealtt]

Thanks Scotty, it is 3-core, I will have a look at where it terminates and check that. In either case I guess I can just add some on in the new junction box anyway for extra peace of mind.

[ruggedscotty]

444.5.2 Equipotential bonding networks
The structure selected for these conductors shall be appropriate for the installation:

(i) Metal sheaths, screens or armouring of cables shall be bonded to the common bonding network (CBN)
unless such bonding is required to be omitted for safety reasons

543.2 Types of protective conductor
543.2.1 A protective conductor may consist of one or more of the following:
(i) A single-core cable
(ii) A conductor in a cable
(iii) An insulated or bare conductor in a common enclosure with insulated live conductors
(iv) A fixed bare or insulated conductor
(v) A metal covering, for example, the sheath, screen or armouring of a cable
(vi) A metal conduit, metallic cable management system or other enclosure or electrically continuous support
system for conductors
(vii) an extraneous-conductive-part complying with Regulation 543.2.6.

So actually the steel wire armour can be used if it is continuious from the consumer board to the point of use.

[ruggedscotty]

I was going through the reg book, but well you have confirmed its three core so thats a relief.

And if your fitting in a new box ideal to add in some FP's and link them. job jobbed...